diff options
Diffstat (limited to 'arch/powerpc/platforms/512x')
| -rw-r--r-- | arch/powerpc/platforms/512x/Kconfig | 2 | ||||
| -rw-r--r-- | arch/powerpc/platforms/512x/Makefile | 3 | ||||
| -rw-r--r-- | arch/powerpc/platforms/512x/clock-commonclk.c | 1221 | ||||
| -rw-r--r-- | arch/powerpc/platforms/512x/clock.c | 754 | ||||
| -rw-r--r-- | arch/powerpc/platforms/512x/mpc512x_shared.c | 169 |
5 files changed, 1316 insertions, 833 deletions
diff --git a/arch/powerpc/platforms/512x/Kconfig b/arch/powerpc/platforms/512x/Kconfig index fc9c1cbfcb1d..5aa3f4b5332c 100644 --- a/arch/powerpc/platforms/512x/Kconfig +++ b/arch/powerpc/platforms/512x/Kconfig @@ -1,9 +1,9 @@ config PPC_MPC512x bool "512x-based boards" depends on 6xx + select COMMON_CLK select FSL_SOC select IPIC - select PPC_CLOCK select PPC_PCI_CHOICE select FSL_PCI if PCI select ARCH_WANT_OPTIONAL_GPIOLIB diff --git a/arch/powerpc/platforms/512x/Makefile b/arch/powerpc/platforms/512x/Makefile index 72fb9340e09f..01693121a2b1 100644 --- a/arch/powerpc/platforms/512x/Makefile +++ b/arch/powerpc/platforms/512x/Makefile @@ -1,7 +1,8 @@ # # Makefile for the Freescale PowerPC 512x linux kernel. # -obj-y += clock.o mpc512x_shared.o +obj-$(CONFIG_COMMON_CLK) += clock-commonclk.o +obj-y += mpc512x_shared.o obj-$(CONFIG_MPC5121_ADS) += mpc5121_ads.o mpc5121_ads_cpld.o obj-$(CONFIG_MPC512x_GENERIC) += mpc512x_generic.o obj-$(CONFIG_PDM360NG) += pdm360ng.o diff --git a/arch/powerpc/platforms/512x/clock-commonclk.c b/arch/powerpc/platforms/512x/clock-commonclk.c new file mode 100644 index 000000000000..6eb614a271fb --- /dev/null +++ b/arch/powerpc/platforms/512x/clock-commonclk.c @@ -0,0 +1,1221 @@ +/* + * Copyright (C) 2013 DENX Software Engineering + * + * Gerhard Sittig, <gsi@denx.de> + * + * common clock driver support for the MPC512x platform + * + * This is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/bitops.h> +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <asm/mpc5121.h> +#include <dt-bindings/clock/mpc512x-clock.h> + +#include "mpc512x.h" /* our public mpc5121_clk_init() API */ + +/* helpers to keep the MCLK intermediates "somewhere" in our table */ +enum { + MCLK_IDX_MUX0, + MCLK_IDX_EN0, + MCLK_IDX_DIV0, + MCLK_MAX_IDX, +}; + +#define NR_PSCS 12 +#define NR_MSCANS 4 +#define NR_SPDIFS 1 +#define NR_OUTCLK 4 +#define NR_MCLKS (NR_PSCS + NR_MSCANS + NR_SPDIFS + NR_OUTCLK) + +/* extend the public set of clocks by adding internal slots for management */ +enum { + /* arrange for adjacent numbers after the public set */ + MPC512x_CLK_START_PRIVATE = MPC512x_CLK_LAST_PUBLIC, + /* clocks which aren't announced to the public */ + MPC512x_CLK_DDR, + MPC512x_CLK_MEM, + MPC512x_CLK_IIM, + /* intermediates in div+gate combos or fractional dividers */ + MPC512x_CLK_DDR_UG, + MPC512x_CLK_SDHC_x4, + MPC512x_CLK_SDHC_UG, + MPC512x_CLK_SDHC2_UG, + MPC512x_CLK_DIU_x4, + MPC512x_CLK_DIU_UG, + MPC512x_CLK_MBX_BUS_UG, + MPC512x_CLK_MBX_UG, + MPC512x_CLK_MBX_3D_UG, + MPC512x_CLK_PCI_UG, + MPC512x_CLK_NFC_UG, + MPC512x_CLK_LPC_UG, + MPC512x_CLK_SPDIF_TX_IN, + /* intermediates for the mux+gate+div+mux MCLK generation */ + MPC512x_CLK_MCLKS_FIRST, + MPC512x_CLK_MCLKS_LAST = MPC512x_CLK_MCLKS_FIRST + + NR_MCLKS * MCLK_MAX_IDX, + /* internal, symbolic spec for the number of slots */ + MPC512x_CLK_LAST_PRIVATE, +}; + +/* data required for the OF clock provider registration */ +static struct clk *clks[MPC512x_CLK_LAST_PRIVATE]; +static struct clk_onecell_data clk_data; + +/* CCM register access */ +static struct mpc512x_ccm __iomem *clkregs; +static DEFINE_SPINLOCK(clklock); + +/* SoC variants {{{ */ + +/* + * tell SoC variants apart as they are rather similar yet not identical, + * cache the result in an enum to not repeatedly run the expensive OF test + * + * MPC5123 is an MPC5121 without the MBX graphics accelerator + * + * MPC5125 has many more differences: no MBX, no AXE, no VIU, no SPDIF, + * no PATA, no SATA, no PCI, two FECs (of different compatibility name), + * only 10 PSCs (of different compatibility name), two SDHCs, different + * NFC IP block, output clocks, system PLL status query, different CPMF + * interpretation, no CFM, different fourth PSC/CAN mux0 input -- yet + * those differences can get folded into this clock provider support + * code and don't warrant a separate highly redundant implementation + */ + +static enum soc_type { + MPC512x_SOC_MPC5121, + MPC512x_SOC_MPC5123, + MPC512x_SOC_MPC5125, +} soc; + +static void mpc512x_clk_determine_soc(void) +{ + if (of_machine_is_compatible("fsl,mpc5121")) { + soc = MPC512x_SOC_MPC5121; + return; + } + if (of_machine_is_compatible("fsl,mpc5123")) { + soc = MPC512x_SOC_MPC5123; + return; + } + if (of_machine_is_compatible("fsl,mpc5125")) { + soc = MPC512x_SOC_MPC5125; + return; + } +} + +static bool soc_has_mbx(void) +{ + if (soc == MPC512x_SOC_MPC5121) + return true; + return false; +} + +static bool soc_has_axe(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_viu(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_spdif(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_pata(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_sata(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_pci(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return false; + return true; +} + +static bool soc_has_fec2(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +static int soc_max_pscnum(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return 10; + return 12; +} + +static bool soc_has_sdhc2(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +static bool soc_has_nfc_5125(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +static bool soc_has_outclk(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +static bool soc_has_cpmf_0_bypass(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +static bool soc_has_mclk_mux0_canin(void) +{ + if (soc == MPC512x_SOC_MPC5125) + return true; + return false; +} + +/* }}} SoC variants */ +/* common clk API wrappers {{{ */ + +/* convenience wrappers around the common clk API */ +static inline struct clk *mpc512x_clk_fixed(const char *name, int rate) +{ + return clk_register_fixed_rate(NULL, name, NULL, CLK_IS_ROOT, rate); +} + +static inline struct clk *mpc512x_clk_factor( + const char *name, const char *parent_name, + int mul, int div) +{ + int clkflags; + + clkflags = CLK_SET_RATE_PARENT; + return clk_register_fixed_factor(NULL, name, parent_name, clkflags, + mul, div); +} + +static inline struct clk *mpc512x_clk_divider( + const char *name, const char *parent_name, u8 clkflags, + u32 __iomem *reg, u8 pos, u8 len, int divflags) +{ + return clk_register_divider(NULL, name, parent_name, clkflags, + reg, pos, len, divflags, &clklock); +} + +static inline struct clk *mpc512x_clk_divtable( + const char *name, const char *parent_name, + u32 __iomem *reg, u8 pos, u8 len, + const struct clk_div_table *divtab) +{ + u8 divflags; + + divflags = 0; + return clk_register_divider_table(NULL, name, parent_name, 0, + reg, pos, len, divflags, + divtab, &clklock); +} + +static inline struct clk *mpc512x_clk_gated( + const char *name, const char *parent_name, + u32 __iomem *reg, u8 pos) +{ + int clkflags; + + clkflags = CLK_SET_RATE_PARENT; + return clk_register_gate(NULL, name, parent_name, clkflags, + reg, pos, 0, &clklock); +} + +static inline struct clk *mpc512x_clk_muxed(const char *name, + const char **parent_names, int parent_count, + u32 __iomem *reg, u8 pos, u8 len) +{ + int clkflags; + u8 muxflags; + + clkflags = CLK_SET_RATE_PARENT; + muxflags = 0; + return clk_register_mux(NULL, name, + parent_names, parent_count, clkflags, + reg, pos, len, muxflags, &clklock); +} + +/* }}} common clk API wrappers */ + +/* helper to isolate a bit field from a register */ +static inline int get_bit_field(uint32_t __iomem *reg, uint8_t pos, uint8_t len) +{ + uint32_t val; + + val = in_be32(reg); + val >>= pos; + val &= (1 << len) - 1; + return val; +} + +/* get the SPMF and translate it into the "sys pll" multiplier */ +static int get_spmf_mult(void) +{ + static int spmf_to_mult[] = { + 68, 1, 12, 16, 20, 24, 28, 32, + 36, 40, 44, 48, 52, 56, 60, 64, + }; + int spmf; + + spmf = get_bit_field(&clkregs->spmr, 24, 4); + return spmf_to_mult[spmf]; +} + +/* + * get the SYS_DIV value and translate it into a divide factor + * + * values returned from here are a multiple of the real factor since the + * divide ratio is fractional + */ +static int get_sys_div_x2(void) +{ + static int sysdiv_code_to_x2[] = { + 4, 5, 6, 7, 8, 9, 10, 14, + 12, 16, 18, 22, 20, 24, 26, 30, + 28, 32, 34, 38, 36, 40, 42, 46, + 44, 48, 50, 54, 52, 56, 58, 62, + 60, 64, 66, + }; + int divcode; + + divcode = get_bit_field(&clkregs->scfr2, 26, 6); + return sysdiv_code_to_x2[divcode]; +} + +/* + * get the CPMF value and translate it into a multiplier factor + * + * values returned from here are a multiple of the real factor since the + * multiplier ratio is fractional + */ +static int get_cpmf_mult_x2(void) +{ + static int cpmf_to_mult_x36[] = { + /* 0b000 is "times 36" */ + 72, 2, 2, 3, 4, 5, 6, 7, + }; + static int cpmf_to_mult_0by[] = { + /* 0b000 is "bypass" */ + 2, 2, 2, 3, 4, 5, 6, 7, + }; + + int *cpmf_to_mult; + int cpmf; + + cpmf = get_bit_field(&clkregs->spmr, 16, 4); + if (soc_has_cpmf_0_bypass()) + cpmf_to_mult = cpmf_to_mult_0by; + else + cpmf_to_mult = cpmf_to_mult_x36; + return cpmf_to_mult[cpmf]; +} + +/* + * some of the clock dividers do scale in a linear way, yet not all of + * their bit combinations are legal; use a divider table to get a + * resulting set of applicable divider values + */ + +/* applies to the IPS_DIV, and PCI_DIV values */ +static struct clk_div_table divtab_2346[] = { + { .val = 2, .div = 2, }, + { .val = 3, .div = 3, }, + { .val = 4, .div = 4, }, + { .val = 6, .div = 6, }, + { .div = 0, }, +}; + +/* applies to the MBX_DIV, LPC_DIV, and NFC_DIV values */ +static struct clk_div_table divtab_1234[] = { + { .val = 1, .div = 1, }, + { .val = 2, .div = 2, }, + { .val = 3, .div = 3, }, + { .val = 4, .div = 4, }, + { .div = 0, }, +}; + +static int get_freq_from_dt(char *propname) +{ + struct device_node *np; + const unsigned int *prop; + int val; + + val = 0; + np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-immr"); + if (np) { + prop = of_get_property(np, propname, NULL); + if (prop) + val = *prop; + of_node_put(np); + } + return val; +} + +static void mpc512x_clk_preset_data(void) +{ + size_t i; + + for (i = 0; i < ARRAY_SIZE(clks); i++) + clks[i] = ERR_PTR(-ENODEV); +} + +/* + * - receives the "bus frequency" from the caller (that's the IPS clock + * rate, the historical source of clock information) + * - fetches the system PLL multiplier and divider values as well as the + * IPS divider value from hardware + * - determines the REF clock rate either from the XTAL/OSC spec (if + * there is a device tree node describing the oscillator) or from the + * IPS bus clock (supported for backwards compatibility, such that + * setups without XTAL/OSC specs keep working) + * - creates the "ref" clock item in the clock tree, such that + * subsequent code can create the remainder of the hierarchy (REF -> + * SYS -> CSB -> IPS) from the REF clock rate and the returned mul/div + * values + */ +static void mpc512x_clk_setup_ref_clock(struct device_node *np, int bus_freq, + int *sys_mul, int *sys_div, + int *ips_div) +{ + struct clk *osc_clk; + int calc_freq; + + /* fetch mul/div factors from the hardware */ + *sys_mul = get_spmf_mult(); + *sys_mul *= 2; /* compensate for the fractional divider */ + *sys_div = get_sys_div_x2(); + *ips_div = get_bit_field(&clkregs->scfr1, 23, 3); + + /* lookup the oscillator clock for its rate */ + osc_clk = of_clk_get_by_name(np, "osc"); + + /* + * either descend from OSC to REF (and in bypassing verify the + * IPS rate), or backtrack from IPS and multiplier values that + * were fetched from hardware to REF and thus to the OSC value + * + * in either case the REF clock gets created here and the + * remainder of the clock tree can get spanned from there + */ + if (!IS_ERR(osc_clk)) { + clks[MPC512x_CLK_REF] = mpc512x_clk_factor("ref", "osc", 1, 1); + calc_freq = clk_get_rate(clks[MPC512x_CLK_REF]); + calc_freq *= *sys_mul; + calc_freq /= *sys_div; + calc_freq /= 2; + calc_freq /= *ips_div; + if (bus_freq && calc_freq != bus_freq) + pr_warn("calc rate %d != OF spec %d\n", + calc_freq, bus_freq); + } else { + calc_freq = bus_freq; /* start with IPS */ + calc_freq *= *ips_div; /* IPS -> CSB */ + calc_freq *= 2; /* CSB -> SYS */ + calc_freq *= *sys_div; /* SYS -> PLL out */ + calc_freq /= *sys_mul; /* PLL out -> REF == OSC */ + clks[MPC512x_CLK_REF] = mpc512x_clk_fixed("ref", calc_freq); + } +} + +/* MCLK helpers {{{ */ + +/* + * helper code for the MCLK subtree setup + * + * the overview in section 5.2.4 of the MPC5121e Reference Manual rev4 + * suggests that all instances of the "PSC clock generation" are equal, + * and that one might re-use the PSC setup for MSCAN clock generation + * (section 5.2.5) as well, at least the logic if not the data for + * description + * + * the details (starting at page 5-20) show differences in the specific + * inputs of the first mux stage ("can clk in", "spdif tx"), and the + * factual non-availability of the second mux stage (it's present yet + * only one input is valid) + * + * the MSCAN clock related registers (starting at page 5-35) all + * reference "spdif clk" at the first mux stage and don't mention any + * "can clk" at all, which somehow is unexpected + * + * TODO re-check the document, and clarify whether the RM is correct in + * the overview or in the details, and whether the difference is a + * clipboard induced error or results from chip revisions + * + * it turns out that the RM rev4 as of 2012-06 talks about "can" for the + * PSCs while RM rev3 as of 2008-10 talks about "spdif", so I guess that + * first a doc update is required which better reflects reality in the + * SoC before the implementation should follow while no questions remain + */ + +/* + * note that this declaration raises a checkpatch warning, but + * it's the very data type dictated by <linux/clk-provider.h>, + * "fixing" this warning will break compilation + */ +static const char *parent_names_mux0_spdif[] = { + "sys", "ref", "psc-mclk-in", "spdif-tx", +}; + +static const char *parent_names_mux0_canin[] = { + "sys", "ref", "psc-mclk-in", "can-clk-in", +}; + +enum mclk_type { + MCLK_TYPE_PSC, + MCLK_TYPE_MSCAN, + MCLK_TYPE_SPDIF, + MCLK_TYPE_OUTCLK, +}; + +struct mclk_setup_data { + enum mclk_type type; + bool has_mclk1; + const char *name_mux0; + const char *name_en0; + const char *name_div0; + const char *parent_names_mux1[2]; + const char *name_mclk; +}; + +#define MCLK_SETUP_DATA_PSC(id) { \ + MCLK_TYPE_PSC, 0, \ + "psc" #id "-mux0", \ + "psc" #id "-en0", \ + "psc" #id "_mclk_div", \ + { "psc" #id "_mclk_div", "dummy", }, \ + "psc" #id "_mclk", \ +} + +#define MCLK_SETUP_DATA_MSCAN(id) { \ + MCLK_TYPE_MSCAN, 0, \ + "mscan" #id "-mux0", \ + "mscan" #id "-en0", \ + "mscan" #id "_mclk_div", \ + { "mscan" #id "_mclk_div", "dummy", }, \ + "mscan" #id "_mclk", \ +} + +#define MCLK_SETUP_DATA_SPDIF { \ + MCLK_TYPE_SPDIF, 1, \ + "spdif-mux0", \ + "spdif-en0", \ + "spdif_mclk_div", \ + { "spdif_mclk_div", "spdif-rx", }, \ + "spdif_mclk", \ +} + +#define MCLK_SETUP_DATA_OUTCLK(id) { \ + MCLK_TYPE_OUTCLK, 0, \ + "out" #id "-mux0", \ + "out" #id "-en0", \ + "out" #id "_mclk_div", \ + { "out" #id "_mclk_div", "dummy", }, \ + "out" #id "_clk", \ +} + +static struct mclk_setup_data mclk_psc_data[] = { + MCLK_SETUP_DATA_PSC(0), + MCLK_SETUP_DATA_PSC(1), + MCLK_SETUP_DATA_PSC(2), + MCLK_SETUP_DATA_PSC(3), + MCLK_SETUP_DATA_PSC(4), + MCLK_SETUP_DATA_PSC(5), + MCLK_SETUP_DATA_PSC(6), + MCLK_SETUP_DATA_PSC(7), + MCLK_SETUP_DATA_PSC(8), + MCLK_SETUP_DATA_PSC(9), + MCLK_SETUP_DATA_PSC(10), + MCLK_SETUP_DATA_PSC(11), +}; + +static struct mclk_setup_data mclk_mscan_data[] = { + MCLK_SETUP_DATA_MSCAN(0), + MCLK_SETUP_DATA_MSCAN(1), + MCLK_SETUP_DATA_MSCAN(2), + MCLK_SETUP_DATA_MSCAN(3), +}; + +static struct mclk_setup_data mclk_spdif_data[] = { + MCLK_SETUP_DATA_SPDIF, +}; + +static struct mclk_setup_data mclk_outclk_data[] = { + MCLK_SETUP_DATA_OUTCLK(0), + MCLK_SETUP_DATA_OUTCLK(1), + MCLK_SETUP_DATA_OUTCLK(2), + MCLK_SETUP_DATA_OUTCLK(3), +}; + +/* setup the MCLK clock subtree of an individual PSC/MSCAN/SPDIF */ +static void mpc512x_clk_setup_mclk(struct mclk_setup_data *entry, size_t idx) +{ + size_t clks_idx_pub, clks_idx_int; + u32 __iomem *mccr_reg; /* MCLK control register (mux, en, div) */ + int div; + + /* derive a few parameters from the component type and index */ + switch (entry->type) { + case MCLK_TYPE_PSC: + clks_idx_pub = MPC512x_CLK_PSC0_MCLK + idx; + clks_idx_int = MPC512x_CLK_MCLKS_FIRST + + (idx) * MCLK_MAX_IDX; + mccr_reg = &clkregs->psc_ccr[idx]; + break; + case MCLK_TYPE_MSCAN: + clks_idx_pub = MPC512x_CLK_MSCAN0_MCLK + idx; + clks_idx_int = MPC512x_CLK_MCLKS_FIRST + + (NR_PSCS + idx) * MCLK_MAX_IDX; + mccr_reg = &clkregs->mscan_ccr[idx]; + break; + case MCLK_TYPE_SPDIF: + clks_idx_pub = MPC512x_CLK_SPDIF_MCLK; + clks_idx_int = MPC512x_CLK_MCLKS_FIRST + + (NR_PSCS + NR_MSCANS) * MCLK_MAX_IDX; + mccr_reg = &clkregs->spccr; + break; + case MCLK_TYPE_OUTCLK: + clks_idx_pub = MPC512x_CLK_OUT0_CLK + idx; + clks_idx_int = MPC512x_CLK_MCLKS_FIRST + + (NR_PSCS + NR_MSCANS + NR_SPDIFS + idx) + * MCLK_MAX_IDX; + mccr_reg = &clkregs->out_ccr[idx]; + break; + default: + return; + } + + /* + * this was grabbed from the PPC_CLOCK implementation, which + * enforced a specific MCLK divider while the clock was gated + * during setup (that's a documented hardware requirement) + * + * the PPC_CLOCK implementation might even have violated the + * "MCLK <= IPS" constraint, the fixed divider value of 1 + * results in a divider of 2 and thus MCLK = SYS/2 which equals + * CSB which is greater than IPS; the serial port setup may have + * adjusted the divider which the clock setup might have left in + * an undesirable state + * + * initial setup is: + * - MCLK 0 from SYS + * - MCLK DIV such to not exceed the IPS clock + * - MCLK 0 enabled + * - MCLK 1 from MCLK DIV + */ + div = clk_get_rate(clks[MPC512x_CLK_SYS]); + div /= clk_get_rate(clks[MPC512x_CLK_IPS]); + out_be32(mccr_reg, (0 << 16)); + out_be32(mccr_reg, (0 << 16) | ((div - 1) << 17)); + out_be32(mccr_reg, (1 << 16) | ((div - 1) << 17)); + + /* + * create the 'struct clk' items of the MCLK's clock subtree + * + * note that by design we always create all nodes and won't take + * shortcuts here, because + * - the "internal" MCLK_DIV and MCLK_OUT signal in turn are + * selectable inputs to the CFM while those who "actually use" + * the PSC/MSCAN/SPDIF (serial drivers et al) need the MCLK + * for their bitrate + * - in the absence of "aliases" for clocks we need to create + * individial 'struct clk' items for whatever might get + * referenced or looked up, even if several of those items are + * identical from the logical POV (their rate value) + * - for easier future maintenance and for better reflection of + * the SoC's documentation, it appears appropriate to generate + * clock items even for those muxers which actually are NOPs + * (those with two inputs of which one is reserved) + */ + clks[clks_idx_int + MCLK_IDX_MUX0] = mpc512x_clk_muxed( + entry->name_mux0, + soc_has_mclk_mux0_canin() + ? &parent_names_mux0_canin[0] + : &parent_names_mux0_spdif[0], + ARRAY_SIZE(parent_names_mux0_spdif), + mccr_reg, 14, 2); + clks[clks_idx_int + MCLK_IDX_EN0] = mpc512x_clk_gated( + entry->name_en0, entry->name_mux0, + mccr_reg, 16); + clks[clks_idx_int + MCLK_IDX_DIV0] = mpc512x_clk_divider( + entry->name_div0, + entry->name_en0, CLK_SET_RATE_GATE, + mccr_reg, 17, 15, 0); + if (entry->has_mclk1) { + clks[clks_idx_pub] = mpc512x_clk_muxed( + entry->name_mclk, + &entry->parent_names_mux1[0], + ARRAY_SIZE(entry->parent_names_mux1), + mccr_reg, 7, 1); + } else { + clks[clks_idx_pub] = mpc512x_clk_factor( + entry->name_mclk, + entry->parent_names_mux1[0], + 1, 1); + } +} + +/* }}} MCLK helpers */ + +static void mpc512x_clk_setup_clock_tree(struct device_node *np, int busfreq) +{ + int sys_mul, sys_div, ips_div; + int mul, div; + size_t mclk_idx; + int freq; + + /* + * developer's notes: + * - consider whether to handle clocks which have both gates and + * dividers via intermediates or by means of composites + * - fractional dividers appear to not map well to composites + * since they can be seen as a fixed multiplier and an + * adjustable divider, while composites can only combine at + * most one of a mux, div, and gate each into one 'struct clk' + * item + * - PSC/MSCAN/SPDIF clock generation OTOH already is very + * specific and cannot get mapped to componsites (at least not + * a single one, maybe two of them, but then some of these + * intermediate clock signals get referenced elsewhere (e.g. + * in the clock frequency measurement, CFM) and thus need + * publicly available names + * - the current source layout appropriately reflects the + * hardware setup, and it works, so it's questionable whether + * further changes will result in big enough a benefit + */ + + /* regardless of whether XTAL/OSC exists, have REF created */ + mpc512x_clk_setup_ref_clock(np, busfreq, &sys_mul, &sys_div, &ips_div); + + /* now setup the REF -> SYS -> CSB -> IPS hierarchy */ + clks[MPC512x_CLK_SYS] = mpc512x_clk_factor("sys", "ref", + sys_mul, sys_div); + clks[MPC512x_CLK_CSB] = mpc512x_clk_factor("csb", "sys", 1, 2); + clks[MPC512x_CLK_IPS] = mpc512x_clk_divtable("ips", "csb", + &clkregs->scfr1, 23, 3, + divtab_2346); + /* now setup anything below SYS and CSB and IPS */ + + clks[MPC512x_CLK_DDR_UG] = mpc512x_clk_factor("ddr-ug", "sys", 1, 2); + + /* + * the Reference Manual discusses that for SDHC only even divide + * ratios are supported because clock domain synchronization + * between 'per' and 'ipg' is broken; + * keep the divider's bit 0 cleared (per reset value), and only + * allow to setup the divider's bits 7:1, which results in that + * only even divide ratios can get configured upon rate changes; + * keep the "x4" name because this bit shift hack is an internal + * implementation detail, the "fractional divider with quarters" + * semantics remains + */ + clks[MPC512x_CLK_SDHC_x4] = mpc512x_clk_factor("sdhc-x4", "csb", 2, 1); + clks[MPC512x_CLK_SDHC_UG] = mpc512x_clk_divider("sdhc-ug", "sdhc-x4", 0, + &clkregs->scfr2, 1, 7, + CLK_DIVIDER_ONE_BASED); + if (soc_has_sdhc2()) { + clks[MPC512x_CLK_SDHC2_UG] = mpc512x_clk_divider( + "sdhc2-ug", "sdhc-x4", 0, &clkregs->scfr2, + 9, 7, CLK_DIVIDER_ONE_BASED); + } + + clks[MPC512x_CLK_DIU_x4] = mpc512x_clk_factor("diu-x4", "csb", 4, 1); + clks[MPC512x_CLK_DIU_UG] = mpc512x_clk_divider("diu-ug", "diu-x4", 0, + &clkregs->scfr1, 0, 8, + CLK_DIVIDER_ONE_BASED); + + /* + * the "power architecture PLL" was setup from data which was + * sampled from the reset config word, at this point in time the + * configuration can be considered fixed and read only (i.e. no + * longer adjustable, or no longer in need of adjustment), which + * is why we don't register a PLL here but assume fixed factors + */ + mul = get_cpmf_mult_x2(); + div = 2; /* compensate for the fractional factor */ + clks[MPC512x_CLK_E300] = mpc512x_clk_factor("e300", "csb", mul, div); + + if (soc_has_mbx()) { + clks[MPC512x_CLK_MBX_BUS_UG] = mpc512x_clk_factor( + "mbx-bus-ug", "csb", 1, 2); + clks[MPC512x_CLK_MBX_UG] = mpc512x_clk_divtable( + "mbx-ug", "mbx-bus-ug", &clkregs->scfr1, + 14, 3, divtab_1234); + clks[MPC512x_CLK_MBX_3D_UG] = mpc512x_clk_factor( + "mbx-3d-ug", "mbx-ug", 1, 1); + } + if (soc_has_pci()) { + clks[MPC512x_CLK_PCI_UG] = mpc512x_clk_divtable( + "pci-ug", "csb", &clkregs->scfr1, + 20, 3, divtab_2346); + } + if (soc_has_nfc_5125()) { + /* + * XXX TODO implement 5125 NFC clock setup logic, + * with high/low period counters in clkregs->scfr3, + * currently there are no users so it's ENOIMPL + */ + clks[MPC512x_CLK_NFC_UG] = ERR_PTR(-ENOTSUPP); + } else { + clks[MPC512x_CLK_NFC_UG] = mpc512x_clk_divtable( + "nfc-ug", "ips", &clkregs->scfr1, + 8, 3, divtab_1234); + } + clks[MPC512x_CLK_LPC_UG] = mpc512x_clk_divtable("lpc-ug", "ips", + &clkregs->scfr1, 11, 3, + divtab_1234); + + clks[MPC512x_CLK_LPC] = mpc512x_clk_gated("lpc", "lpc-ug", + &clkregs->sccr1, 30); + clks[MPC512x_CLK_NFC] = mpc512x_clk_gated("nfc", "nfc-ug", + &clkregs->sccr1, 29); + if (soc_has_pata()) { + clks[MPC512x_CLK_PATA] = mpc512x_clk_gated( + "pata", "ips", &clkregs->sccr1, 28); + } + /* for PSCs there is a "registers" gate and a bitrate MCLK subtree */ + for (mclk_idx = 0; mclk_idx < soc_max_pscnum(); mclk_idx++) { + char name[12]; + snprintf(name, sizeof(name), "psc%d", mclk_idx); + clks[MPC512x_CLK_PSC0 + mclk_idx] = mpc512x_clk_gated( + name, "ips", &clkregs->sccr1, 27 - mclk_idx); + mpc512x_clk_setup_mclk(&mclk_psc_data[mclk_idx], mclk_idx); + } + clks[MPC512x_CLK_PSC_FIFO] = mpc512x_clk_gated("psc-fifo", "ips", + &clkregs->sccr1, 15); + if (soc_has_sata()) { + clks[MPC512x_CLK_SATA] = mpc512x_clk_gated( + "sata", "ips", &clkregs->sccr1, 14); + } + clks[MPC512x_CLK_FEC] = mpc512x_clk_gated("fec", "ips", + &clkregs->sccr1, 13); + if (soc_has_pci()) { + clks[MPC512x_CLK_PCI] = mpc512x_clk_gated( + "pci", "pci-ug", &clkregs->sccr1, 11); + } + clks[MPC512x_CLK_DDR] = mpc512x_clk_gated("ddr", "ddr-ug", + &clkregs->sccr1, 10); + if (soc_has_fec2()) { + clks[MPC512x_CLK_FEC2] = mpc512x_clk_gated( + "fec2", "ips", &clkregs->sccr1, 9); + } + + clks[MPC512x_CLK_DIU] = mpc512x_clk_gated("diu", "diu-ug", + &clkregs->sccr2, 31); + if (soc_has_axe()) { + clks[MPC512x_CLK_AXE] = mpc512x_clk_gated( + "axe", "csb", &clkregs->sccr2, 30); + } + clks[MPC512x_CLK_MEM] = mpc512x_clk_gated("mem", "ips", + &clkregs->sccr2, 29); + clks[MPC512x_CLK_USB1] = mpc512x_clk_gated("usb1", "csb", + &clkregs->sccr2, 28); + clks[MPC512x_CLK_USB2] = mpc512x_clk_gated("usb2", "csb", + &clkregs->sccr2, 27); + clks[MPC512x_CLK_I2C] = mpc512x_clk_gated("i2c", "ips", + &clkregs->sccr2, 26); + /* MSCAN differs from PSC with just one gate for multiple components */ + clks[MPC512x_CLK_BDLC] = mpc512x_clk_gated("bdlc", "ips", + &clkregs->sccr2, 25); + for (mclk_idx = 0; mclk_idx < ARRAY_SIZE(mclk_mscan_data); mclk_idx++) + mpc512x_clk_setup_mclk(&mclk_mscan_data[mclk_idx], mclk_idx); + clks[MPC512x_CLK_SDHC] = mpc512x_clk_gated("sdhc", "sdhc-ug", + &clkregs->sccr2, 24); + /* there is only one SPDIF component, which shares MCLK support code */ + if (soc_has_spdif()) { + clks[MPC512x_CLK_SPDIF] = mpc512x_clk_gated( + "spdif", "ips", &clkregs->sccr2, 23); + mpc512x_clk_setup_mclk(&mclk_spdif_data[0], 0); + } + if (soc_has_mbx()) { + clks[MPC512x_CLK_MBX_BUS] = mpc512x_clk_gated( + "mbx-bus", "mbx-bus-ug", &clkregs->sccr2, 22); + clks[MPC512x_CLK_MBX] = mpc512x_clk_gated( + "mbx", "mbx-ug", &clkregs->sccr2, 21); + clks[MPC512x_CLK_MBX_3D] = mpc512x_clk_gated( + "mbx-3d", "mbx-3d-ug", &clkregs->sccr2, 20); + } + clks[MPC512x_CLK_IIM] = mpc512x_clk_gated("iim", "csb", + &clkregs->sccr2, 19); + if (soc_has_viu()) { + clks[MPC512x_CLK_VIU] = mpc512x_clk_gated( + "viu", "csb", &clkregs->sccr2, 18); + } + if (soc_has_sdhc2()) { + clks[MPC512x_CLK_SDHC2] = mpc512x_clk_gated( + "sdhc-2", "sdhc2-ug", &clkregs->sccr2, 17); + } + + if (soc_has_outclk()) { + size_t idx; /* used as mclk_idx, just to trim line length */ + for (idx = 0; idx < ARRAY_SIZE(mclk_outclk_data); idx++) + mpc512x_clk_setup_mclk(&mclk_outclk_data[idx], idx); + } + + /* + * externally provided clocks (when implemented in hardware, + * device tree may specify values which otherwise were unknown) + */ + freq = get_freq_from_dt("psc_mclk_in"); + if (!freq) + freq = 25000000; + clks[MPC512x_CLK_PSC_MCLK_IN] = mpc512x_clk_fixed("psc_mclk_in", freq); + if (soc_has_mclk_mux0_canin()) { + freq = get_freq_from_dt("can_clk_in"); + clks[MPC512x_CLK_CAN_CLK_IN] = mpc512x_clk_fixed( + "can_clk_in", freq); + } else { + freq = get_freq_from_dt("spdif_tx_in"); + clks[MPC512x_CLK_SPDIF_TX_IN] = mpc512x_clk_fixed( + "spdif_tx_in", freq); + freq = get_freq_from_dt("spdif_rx_in"); + clks[MPC512x_CLK_SPDIF_TX_IN] = mpc512x_clk_fixed( + "spdif_rx_in", freq); + } + + /* fixed frequency for AC97, always 24.567MHz */ + clks[MPC512x_CLK_AC97] = mpc512x_clk_fixed("ac97", 24567000); + + /* + * pre-enable those "internal" clock items which never get + * claimed by any peripheral driver, to not have the clock + * subsystem disable them late at startup + */ + clk_prepare_enable(clks[MPC512x_CLK_DUMMY]); + clk_prepare_enable(clks[MPC512x_CLK_E300]); /* PowerPC CPU */ + clk_prepare_enable(clks[MPC512x_CLK_DDR]); /* DRAM */ + clk_prepare_enable(clks[MPC512x_CLK_MEM]); /* SRAM */ + clk_prepare_enable(clks[MPC512x_CLK_IPS]); /* SoC periph */ + clk_prepare_enable(clks[MPC512x_CLK_LPC]); /* boot media */ +} + +/* + * registers the set of public clocks (those listed in the dt-bindings/ + * header file) for OF lookups, keeps the intermediates private to us + */ +static void mpc5121_clk_register_of_provider(struct device_node *np) +{ + clk_data.clks = clks; + clk_data.clk_num = MPC512x_CLK_LAST_PUBLIC + 1; /* _not_ ARRAY_SIZE() */ + of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data); +} + +/* + * temporary support for the period of time between introduction of CCF + * support and the adjustment of peripheral drivers to OF based lookups + */ +static void mpc5121_clk_provide_migration_support(void) +{ + + /* + * pre-enable those clock items which are not yet appropriately + * acquired by their peripheral driver + * + * the PCI clock cannot get acquired by its peripheral driver, + * because for this platform the driver won't probe(), instead + * initialization is done from within the .setup_arch() routine + * at a point in time where the clock provider has not been + * setup yet and thus isn't available yet + * + * so we "pre-enable" the clock here, to not have the clock + * subsystem automatically disable this item in a late init call + * + * this PCI clock pre-enable workaround only applies when there + * are device tree nodes for PCI and thus the peripheral driver + * has attached to bridges, otherwise the PCI clock remains + * unused and so it gets disabled + */ + clk_prepare_enable(clks[MPC512x_CLK_PSC3_MCLK]);/* serial console */ + if (of_find_compatible_node(NULL, "pci", "fsl,mpc5121-pci")) + clk_prepare_enable(clks[MPC512x_CLK_PCI]); +} + +/* + * those macros are not exactly pretty, but they encapsulate a lot + * of copy'n'paste heavy code which is even more ugly, and reduce + * the potential for inconsistencies in those many code copies + */ +#define FOR_NODES(compatname) \ + for_each_compatible_node(np, NULL, compatname) + +#define NODE_PREP do { \ + of_address_to_resource(np, 0, &res); \ + snprintf(devname, sizeof(devname), "%08x.%s", res.start, np->name); \ +} while (0) + +#define NODE_CHK(clkname, clkitem, regnode, regflag) do { \ + struct clk *clk; \ + clk = of_clk_get_by_name(np, clkname); \ + if (IS_ERR(clk)) { \ + clk = clkitem; \ + clk_register_clkdev(clk, clkname, devname); \ + if (regnode) \ + clk_register_clkdev(clk, clkname, np->name); \ + did_register |= DID_REG_ ## regflag; \ + pr_debug("clock alias name '%s' for dev '%s' pointer %p\n", \ + clkname, devname, clk); \ + } else { \ + clk_put(clk); \ + } \ +} while (0) + +/* + * register source code provided fallback results for clock lookups, + * these get consulted when OF based clock lookup fails (that is in the + * case of not yet adjusted device tree data, where clock related specs + * are missing) + */ +static void mpc5121_clk_provide_backwards_compat(void) +{ + enum did_reg_flags { + DID_REG_PSC = BIT(0), + DID_REG_PSCFIFO = BIT(1), + DID_REG_NFC = BIT(2), + DID_REG_CAN = BIT(3), + DID_REG_I2C = BIT(4), + DID_REG_DIU = BIT(5), + DID_REG_VIU = BIT(6), + DID_REG_FEC = BIT(7), + DID_REG_USB = BIT(8), + DID_REG_PATA = BIT(9), + }; + + int did_register; + struct device_node *np; + struct resource res; + int idx; + char devname[32]; + + did_register = 0; + + FOR_NODES(mpc512x_select_psc_compat()) { + NODE_PREP; + idx = (res.start >> 8) & 0xf; + NODE_CHK("ipg", clks[MPC512x_CLK_PSC0 + idx], 0, PSC); + NODE_CHK("mclk", clks[MPC512x_CLK_PSC0_MCLK + idx], 0, PSC); + } + + FOR_NODES("fsl,mpc5121-psc-fifo") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_PSC_FIFO], 1, PSCFIFO); + } + + FOR_NODES("fsl,mpc5121-nfc") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_NFC], 0, NFC); + } + + FOR_NODES("fsl,mpc5121-mscan") { + NODE_PREP; + idx = 0; + idx += (res.start & 0x2000) ? 2 : 0; + idx += (res.start & 0x0080) ? 1 : 0; + NODE_CHK("ipg", clks[MPC512x_CLK_BDLC], 0, CAN); + NODE_CHK("mclk", clks[MPC512x_CLK_MSCAN0_MCLK + idx], 0, CAN); + } + + /* + * do register the 'ips', 'sys', and 'ref' names globally + * instead of inside each individual CAN node, as there is no + * potential for a name conflict (in contrast to 'ipg' and 'mclk') + */ + if (did_register & DID_REG_CAN) { + clk_register_clkdev(clks[MPC512x_CLK_IPS], "ips", NULL); + clk_register_clkdev(clks[MPC512x_CLK_SYS], "sys", NULL); + clk_register_clkdev(clks[MPC512x_CLK_REF], "ref", NULL); + } + + FOR_NODES("fsl,mpc5121-i2c") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_I2C], 0, I2C); + } + + /* + * workaround for the fact that the I2C driver does an "anonymous" + * lookup (NULL name spec, which yields the first clock spec) for + * which we cannot register an alias -- a _global_ 'ipg' alias that + * is not bound to any device name and returns the I2C clock item + * is not a good idea + * + * so we have the lookup in the peripheral driver fail, which is + * silent and non-fatal, and pre-enable the clock item here such + * that register access is possible + * + * see commit b3bfce2b "i2c: mpc: cleanup clock API use" for + * details, adjusting s/NULL/"ipg"/ in i2c-mpc.c would make this + * workaround obsolete + */ + if (did_register & DID_REG_I2C) + clk_prepare_enable(clks[MPC512x_CLK_I2C]); + + FOR_NODES("fsl,mpc5121-diu") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_DIU], 1, DIU); + } + + FOR_NODES("fsl,mpc5121-viu") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_VIU], 0, VIU); + } + + /* + * note that 2771399a "fs_enet: cleanup clock API use" did use the + * "per" string for the clock lookup in contrast to the "ipg" name + * which most other nodes are using -- this is not a fatal thing + * but just something to keep in mind when doing compatibility + * registration, it's a non-issue with up-to-date device tree data + */ + FOR_NODES("fsl,mpc5121-fec") { + NODE_PREP; + NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); + } + FOR_NODES("fsl,mpc5121-fec-mdio") { + NODE_PREP; + NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); + } + /* + * MPC5125 has two FECs: FEC1 at 0x2800, FEC2 at 0x4800; + * the clock items don't "form an array" since FEC2 was + * added only later and was not allowed to shift all other + * clock item indices, so the numbers aren't adjacent + */ + FOR_NODES("fsl,mpc5125-fec") { + NODE_PREP; + if (res.start & 0x4000) + idx = MPC512x_CLK_FEC2; + else + idx = MPC512x_CLK_FEC; + NODE_CHK("per", clks[idx], 0, FEC); + } + + FOR_NODES("fsl,mpc5121-usb2-dr") { + NODE_PREP; + idx = (res.start & 0x4000) ? 1 : 0; + NODE_CHK("ipg", clks[MPC512x_CLK_USB1 + idx], 0, USB); + } + + FOR_NODES("fsl,mpc5121-pata") { + NODE_PREP; + NODE_CHK("ipg", clks[MPC512x_CLK_PATA], 0, PATA); + } + + /* + * try to collapse diagnostics into a single line of output yet + * provide a full list of what is missing, to avoid noise in the + * absence of up-to-date device tree data -- backwards + * compatibility to old DTBs is a requirement, updates may be + * desirable or preferrable but are not at all mandatory + */ + if (did_register) { + pr_notice("device tree lacks clock specs, adding fallbacks (0x%x,%s%s%s%s%s%s%s%s%s%s)\n", + did_register, + (did_register & DID_REG_PSC) ? " PSC" : "", + (did_register & DID_REG_PSCFIFO) ? " PSCFIFO" : "", + (did_register & DID_REG_NFC) ? " NFC" : "", + (did_register & DID_REG_CAN) ? " CAN" : "", + (did_register & DID_REG_I2C) ? " I2C" : "", + (did_register & DID_REG_DIU) ? " DIU" : "", + (did_register & DID_REG_VIU) ? " VIU" : "", + (did_register & DID_REG_FEC) ? " FEC" : "", + (did_register & DID_REG_USB) ? " USB" : "", + (did_register & DID_REG_PATA) ? " PATA" : ""); + } else { + pr_debug("device tree has clock specs, no fallbacks added\n"); + } +} + +int __init mpc5121_clk_init(void) +{ + struct device_node *clk_np; + int busfreq; + + /* map the clock control registers */ + clk_np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-clock"); + if (!clk_np) + return -ENODEV; + clkregs = of_iomap(clk_np, 0); + WARN_ON(!clkregs); + + /* determine the SoC variant we run on */ + mpc512x_clk_determine_soc(); + + /* invalidate all not yet registered clock slots */ + mpc512x_clk_preset_data(); + + /* + * have the device tree scanned for "fixed-clock" nodes (which + * includes the oscillator node if the board's DT provides one) + */ + of_clk_init(NULL); + + /* + * add a dummy clock for those situations where a clock spec is + * required yet no real clock is involved + */ + clks[MPC512x_CLK_DUMMY] = mpc512x_clk_fixed("dummy", 0); + + /* + * have all the real nodes in the clock tree populated from REF + * down to all leaves, either starting from the OSC node or from + * a REF root that was created from the IPS bus clock input + */ + busfreq = get_freq_from_dt("bus-frequency"); + mpc512x_clk_setup_clock_tree(clk_np, busfreq); + + /* register as an OF clock provider */ + mpc5121_clk_register_of_provider(clk_np); + + /* + * unbreak not yet adjusted peripheral drivers during migration + * towards fully operational common clock support, and allow + * operation in the absence of clock related device tree specs + */ + mpc5121_clk_provide_migration_support(); + mpc5121_clk_provide_backwards_compat(); + + return 0; +} diff --git a/arch/powerpc/platforms/512x/clock.c b/arch/powerpc/platforms/512x/clock.c deleted file mode 100644 index fd8a37653417..000000000000 --- a/arch/powerpc/platforms/512x/clock.c +++ /dev/null @@ -1,754 +0,0 @@ -/* - * Copyright (C) 2007,2008 Freescale Semiconductor, Inc. All rights reserved. - * - * Author: John Rigby <jrigby@freescale.com> - * - * Implements the clk api defined in include/linux/clk.h - * - * Original based on linux/arch/arm/mach-integrator/clock.c - * - * Copyright (C) 2004 ARM Limited. - * Written by Deep Blue Solutions Limited. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include <linux/kernel.h> -#include <linux/list.h> -#include <linux/errno.h> -#include <linux/err.h> -#include <linux/module.h> -#include <linux/string.h> -#include <linux/clk.h> -#include <linux/mutex.h> -#include <linux/io.h> - -#include <linux/of_address.h> -#include <linux/of_platform.h> -#include <asm/mpc5xxx.h> -#include <asm/mpc5121.h> -#include <asm/clk_interface.h> - -#include "mpc512x.h" - -#undef CLK_DEBUG - -static int clocks_initialized; - -#define CLK_HAS_RATE 0x1 /* has rate in MHz */ -#define CLK_HAS_CTRL 0x2 /* has control reg and bit */ - -struct clk { - struct list_head node; - char name[32]; - int flags; - struct device *dev; - unsigned long rate; - struct module *owner; - void (*calc) (struct clk *); - struct clk *parent; - int reg, bit; /* CLK_HAS_CTRL */ - int div_shift; /* only used by generic_div_clk_calc */ -}; - -static LIST_HEAD(clocks); -static DEFINE_MUTEX(clocks_mutex); - -static struct clk *mpc5121_clk_get(struct device *dev, const char *id) -{ - struct clk *p, *clk = ERR_PTR(-ENOENT); - int dev_match; - int id_match; - - if (dev == NULL || id == NULL) - return clk; - - mutex_lock(&clocks_mutex); - list_for_each_entry(p, &clocks, node) { - dev_match = id_match = 0; - - if (dev == p->dev) - dev_match++; - if (strcmp(id, p->name) == 0) - id_match++; - if ((dev_match || id_match) && try_module_get(p->owner)) { - clk = p; - break; - } - } - mutex_unlock(&clocks_mutex); - - return clk; -} - -#ifdef CLK_DEBUG -static void dump_clocks(void) -{ - struct clk *p; - - mutex_lock(&clocks_mutex); - printk(KERN_INFO "CLOCKS:\n"); - list_for_each_entry(p, &clocks, node) { - pr_info(" %s=%ld", p->name, p->rate); - if (p->parent) - pr_cont(" %s=%ld", p->parent->name, - p->parent->rate); - if (p->flags & CLK_HAS_CTRL) - pr_cont(" reg/bit=%d/%d", p->reg, p->bit); - pr_cont("\n"); - } - mutex_unlock(&clocks_mutex); -} -#define DEBUG_CLK_DUMP() dump_clocks() -#else -#define DEBUG_CLK_DUMP() -#endif - - -static void mpc5121_clk_put(struct clk *clk) -{ - module_put(clk->owner); -} - -#define NRPSC 12 - -struct mpc512x_clockctl { - u32 spmr; /* System PLL Mode Reg */ - u32 sccr[2]; /* System Clk Ctrl Reg 1 & 2 */ - u32 scfr1; /* System Clk Freq Reg 1 */ - u32 scfr2; /* System Clk Freq Reg 2 */ - u32 reserved; - u32 bcr; /* Bread Crumb Reg */ - u32 pccr[NRPSC]; /* PSC Clk Ctrl Reg 0-11 */ - u32 spccr; /* SPDIF Clk Ctrl Reg */ - u32 cccr; /* CFM Clk Ctrl Reg */ - u32 dccr; /* DIU Clk Cnfg Reg */ -}; - -static struct mpc512x_clockctl __iomem *clockctl; - -static int mpc5121_clk_enable(struct clk *clk) -{ - unsigned int mask; - - if (clk->flags & CLK_HAS_CTRL) { - mask = in_be32(&clockctl->sccr[clk->reg]); - mask |= 1 << clk->bit; - out_be32(&clockctl->sccr[clk->reg], mask); - } - return 0; -} - -static void mpc5121_clk_disable(struct clk *clk) -{ - unsigned int mask; - - if (clk->flags & CLK_HAS_CTRL) { - mask = in_be32(&clockctl->sccr[clk->reg]); - mask &= ~(1 << clk->bit); - out_be32(&clockctl->sccr[clk->reg], mask); - } -} - -static unsigned long mpc5121_clk_get_rate(struct clk *clk) -{ - if (clk->flags & CLK_HAS_RATE) - return clk->rate; - else - return 0; -} - -static long mpc5121_clk_round_rate(struct clk *clk, unsigned long rate) -{ - return rate; -} - -static int mpc5121_clk_set_rate(struct clk *clk, unsigned long rate) -{ - return 0; -} - -static int clk_register(struct clk *clk) -{ - mutex_lock(&clocks_mutex); - list_add(&clk->node, &clocks); - mutex_unlock(&clocks_mutex); - return 0; -} - -static unsigned long spmf_mult(void) -{ - /* - * Convert spmf to multiplier - */ - static int spmf_to_mult[] = { - 68, 1, 12, 16, - 20, 24, 28, 32, - 36, 40, 44, 48, - 52, 56, 60, 64 - }; - int spmf = (in_be32(&clockctl->spmr) >> 24) & 0xf; - return spmf_to_mult[spmf]; -} - -static unsigned long sysdiv_div_x_2(void) -{ - /* - * Convert sysdiv to divisor x 2 - * Some divisors have fractional parts so - * multiply by 2 then divide by this value - */ - static int sysdiv_to_div_x_2[] = { - 4, 5, 6, 7, - 8, 9, 10, 14, - 12, 16, 18, 22, - 20, 24, 26, 30, - 28, 32, 34, 38, - 36, 40, 42, 46, - 44, 48, 50, 54, - 52, 56, 58, 62, - 60, 64, 66, - }; - int sysdiv = (in_be32(&clockctl->scfr2) >> 26) & 0x3f; - return sysdiv_to_div_x_2[sysdiv]; -} - -static unsigned long ref_to_sys(unsigned long rate) -{ - rate *= spmf_mult(); - rate *= 2; - rate /= sysdiv_div_x_2(); - - return rate; -} - -static unsigned long sys_to_ref(unsigned long rate) -{ - rate *= sysdiv_div_x_2(); - rate /= 2; - rate /= spmf_mult(); - - return rate; -} - -static long ips_to_ref(unsigned long rate) -{ - int ips_div = (in_be32(&clockctl->scfr1) >> 23) & 0x7; - - rate *= ips_div; /* csb_clk = ips_clk * ips_div */ - rate *= 2; /* sys_clk = csb_clk * 2 */ - return sys_to_ref(rate); -} - -static unsigned long devtree_getfreq(char *clockname) -{ - struct device_node *np; - const unsigned int *prop; - unsigned int val = 0; - - np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-immr"); - if (np) { - prop = of_get_property(np, clockname, NULL); - if (prop) - val = *prop; - of_node_put(np); - } - return val; -} - -static void ref_clk_calc(struct clk *clk) -{ - unsigned long rate; - - rate = devtree_getfreq("bus-frequency"); - if (rate == 0) { - printk(KERN_ERR "No bus-frequency in dev tree\n"); - clk->rate = 0; - return; - } - clk->rate = ips_to_ref(rate); -} - -static struct clk ref_clk = { - .name = "ref_clk", - .calc = ref_clk_calc, -}; - - -static void sys_clk_calc(struct clk *clk) -{ - clk->rate = ref_to_sys(ref_clk.rate); -} - -static struct clk sys_clk = { - .name = "sys_clk", - .calc = sys_clk_calc, -}; - -static void diu_clk_calc(struct clk *clk) -{ - int diudiv_x_2 = in_be32(&clockctl->scfr1) & 0xff; - unsigned long rate; - - rate = sys_clk.rate; - - rate *= 2; - rate /= diudiv_x_2; - - clk->rate = rate; -} - -static void viu_clk_calc(struct clk *clk) -{ - unsigned long rate; - - rate = sys_clk.rate; - rate /= 2; - clk->rate = rate; -} - -static void half_clk_calc(struct clk *clk) -{ - clk->rate = clk->parent->rate / 2; -} - -static void generic_div_clk_calc(struct clk *clk) -{ - int div = (in_be32(&clockctl->scfr1) >> clk->div_shift) & 0x7; - - clk->rate = clk->parent->rate / div; -} - -static void unity_clk_calc(struct clk *clk) -{ - clk->rate = clk->parent->rate; -} - -static struct clk csb_clk = { - .name = "csb_clk", - .calc = half_clk_calc, - .parent = &sys_clk, -}; - -static void e300_clk_calc(struct clk *clk) -{ - int spmf = (in_be32(&clockctl->spmr) >> 16) & 0xf; - int ratex2 = clk->parent->rate * spmf; - - clk->rate = ratex2 / 2; -} - -static struct clk e300_clk = { - .name = "e300_clk", - .calc = e300_clk_calc, - .parent = &csb_clk, -}; - -static struct clk ips_clk = { - .name = "ips_clk", - .calc = generic_div_clk_calc, - .parent = &csb_clk, - .div_shift = 23, -}; - -/* - * Clocks controlled by SCCR1 (.reg = 0) - */ -static struct clk lpc_clk = { - .name = "lpc_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 30, - .calc = generic_div_clk_calc, - .parent = &ips_clk, - .div_shift = 11, -}; - -static struct clk nfc_clk = { - .name = "nfc_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 29, - .calc = generic_div_clk_calc, - .parent = &ips_clk, - .div_shift = 8, -}; - -static struct clk pata_clk = { - .name = "pata_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 28, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -/* - * PSC clocks (bits 27 - 16) - * are setup elsewhere - */ - -static struct clk sata_clk = { - .name = "sata_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 14, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -static struct clk fec_clk = { - .name = "fec_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 13, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -static struct clk pci_clk = { - .name = "pci_clk", - .flags = CLK_HAS_CTRL, - .reg = 0, - .bit = 11, - .calc = generic_div_clk_calc, - .parent = &csb_clk, - .div_shift = 20, -}; - -/* - * Clocks controlled by SCCR2 (.reg = 1) - */ -static struct clk diu_clk = { - .name = "diu_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 31, - .calc = diu_clk_calc, -}; - -static struct clk viu_clk = { - .name = "viu_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 18, - .calc = viu_clk_calc, -}; - -static struct clk axe_clk = { - .name = "axe_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 30, - .calc = unity_clk_calc, - .parent = &csb_clk, -}; - -static struct clk usb1_clk = { - .name = "usb1_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 28, - .calc = unity_clk_calc, - .parent = &csb_clk, -}; - -static struct clk usb2_clk = { - .name = "usb2_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 27, - .calc = unity_clk_calc, - .parent = &csb_clk, -}; - -static struct clk i2c_clk = { - .name = "i2c_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 26, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -static struct clk mscan_clk = { - .name = "mscan_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 25, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -static struct clk sdhc_clk = { - .name = "sdhc_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 24, - .calc = unity_clk_calc, - .parent = &ips_clk, -}; - -static struct clk mbx_bus_clk = { - .name = "mbx_bus_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 22, - .calc = half_clk_calc, - .parent = &csb_clk, -}; - -static struct clk mbx_clk = { - .name = "mbx_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 21, - .calc = unity_clk_calc, - .parent = &csb_clk, -}; - -static struct clk mbx_3d_clk = { - .name = "mbx_3d_clk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 20, - .calc = generic_div_clk_calc, - .parent = &mbx_bus_clk, - .div_shift = 14, -}; - -static void psc_mclk_in_calc(struct clk *clk) -{ - clk->rate = devtree_getfreq("psc_mclk_in"); - if (!clk->rate) - clk->rate = 25000000; -} - -static struct clk psc_mclk_in = { - .name = "psc_mclk_in", - .calc = psc_mclk_in_calc, -}; - -static struct clk spdif_txclk = { - .name = "spdif_txclk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 23, -}; - -static struct clk spdif_rxclk = { - .name = "spdif_rxclk", - .flags = CLK_HAS_CTRL, - .reg = 1, - .bit = 23, -}; - -static void ac97_clk_calc(struct clk *clk) -{ - /* ac97 bit clock is always 24.567 MHz */ - clk->rate = 24567000; -} - -static struct clk ac97_clk = { - .name = "ac97_clk_in", - .calc = ac97_clk_calc, -}; - -static struct clk *rate_clks[] = { - &ref_clk, - &sys_clk, - &diu_clk, - &viu_clk, - &csb_clk, - &e300_clk, - &ips_clk, - &fec_clk, - &sata_clk, - &pata_clk, - &nfc_clk, - &lpc_clk, - &mbx_bus_clk, - &mbx_clk, - &mbx_3d_clk, - &axe_clk, - &usb1_clk, - &usb2_clk, - &i2c_clk, - &mscan_clk, - &sdhc_clk, - &pci_clk, - &psc_mclk_in, - &spdif_txclk, - &spdif_rxclk, - &ac97_clk, - NULL -}; - -static void rate_clk_init(struct clk *clk) -{ - if (clk->calc) { - clk->calc(clk); - clk->flags |= CLK_HAS_RATE; - clk_register(clk); - } else { - printk(KERN_WARNING - "Could not initialize clk %s without a calc routine\n", - clk->name); - } -} - -static void rate_clks_init(void) -{ - struct clk **cpp, *clk; - - cpp = rate_clks; - while ((clk = *cpp++)) - rate_clk_init(clk); -} - -/* - * There are two clk enable registers with 32 enable bits each - * psc clocks and device clocks are all stored in dev_clks - */ -static struct clk dev_clks[2][32]; - -/* - * Given a psc number return the dev_clk - * associated with it - */ -static struct clk *psc_dev_clk(int pscnum) -{ - int reg, bit; - struct clk *clk; - - reg = 0; - bit = 27 - pscnum; - - clk = &dev_clks[reg][bit]; - clk->reg = 0; - clk->bit = bit; - return clk; -} - -/* - * PSC clock rate calculation - */ -static void psc_calc_rate(struct clk *clk, int pscnum, struct device_node *np) -{ - unsigned long mclk_src = sys_clk.rate; - unsigned long mclk_div; - - /* - * Can only change value of mclk divider - * when the divider is disabled. - * - * Zero is not a valid divider so minimum - * divider is 1 - * - * disable/set divider/enable - */ - out_be32(&clockctl->pccr[pscnum], 0); - out_be32(&clockctl->pccr[pscnum], 0x00020000); - out_be32(&clockctl->pccr[pscnum], 0x00030000); - - if (in_be32(&clockctl->pccr[pscnum]) & 0x80) { - clk->rate = spdif_rxclk.rate; - return; - } - - switch ((in_be32(&clockctl->pccr[pscnum]) >> 14) & 0x3) { - case 0: - mclk_src = sys_clk.rate; - break; - case 1: - mclk_src = ref_clk.rate; - break; - case 2: - mclk_src = psc_mclk_in.rate; - break; - case 3: - mclk_src = spdif_txclk.rate; - break; - } - - mclk_div = ((in_be32(&clockctl->pccr[pscnum]) >> 17) & 0x7fff) + 1; - clk->rate = mclk_src / mclk_div; -} - -/* - * Find all psc nodes in device tree and assign a clock - * with name "psc%d_mclk" and dev pointing at the device - * returned from of_find_device_by_node - */ -static void psc_clks_init(void) -{ - struct device_node *np; - struct platform_device *ofdev; - u32 reg; - const char *psc_compat; - - psc_compat = mpc512x_select_psc_compat(); - if (!psc_compat) - return; - - for_each_compatible_node(np, NULL, psc_compat) { - if (!of_property_read_u32(np, "reg", ®)) { - int pscnum = (reg & 0xf00) >> 8; - struct clk *clk = psc_dev_clk(pscnum); - - clk->flags = CLK_HAS_RATE | CLK_HAS_CTRL; - ofdev = of_find_device_by_node(np); - clk->dev = &ofdev->dev; - /* - * AC97 is special rate clock does - * not go through normal path - */ - if (of_device_is_compatible(np, "fsl,mpc5121-psc-ac97")) - clk->rate = ac97_clk.rate; - else - psc_calc_rate(clk, pscnum, np); - sprintf(clk->name, "psc%d_mclk", pscnum); - clk_register(clk); - clk_enable(clk); - } - } -} - -static struct clk_interface mpc5121_clk_functions = { - .clk_get = mpc5121_clk_get, - .clk_enable = mpc5121_clk_enable, - .clk_disable = mpc5121_clk_disable, - .clk_get_rate = mpc5121_clk_get_rate, - .clk_put = mpc5121_clk_put, - .clk_round_rate = mpc5121_clk_round_rate, - .clk_set_rate = mpc5121_clk_set_rate, - .clk_set_parent = NULL, - .clk_get_parent = NULL, -}; - -int __init mpc5121_clk_init(void) -{ - struct device_node *np; - - np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-clock"); - if (np) { - clockctl = of_iomap(np, 0); - of_node_put(np); - } - - if (!clockctl) { - printk(KERN_ERR "Could not map clock control registers\n"); - return 0; - } - - rate_clks_init(); - psc_clks_init(); - - /* leave clockctl mapped forever */ - /*iounmap(clockctl); */ - DEBUG_CLK_DUMP(); - clocks_initialized++; - clk_functions = mpc5121_clk_functions; - return 0; -} diff --git a/arch/powerpc/platforms/512x/mpc512x_shared.c b/arch/powerpc/platforms/512x/mpc512x_shared.c index 36b5652aada2..adb95f03d4d4 100644 --- a/arch/powerpc/platforms/512x/mpc512x_shared.c +++ b/arch/powerpc/platforms/512x/mpc512x_shared.c @@ -12,6 +12,7 @@ * (at your option) any later version. */ +#include <linux/clk.h> #include <linux/kernel.h> #include <linux/io.h> #include <linux/irq.h> @@ -68,98 +69,112 @@ struct fsl_diu_shared_fb { bool in_use; }; -#define DIU_DIV_MASK 0x000000ff +/* receives a pixel clock spec in pico seconds, adjusts the DIU clock rate */ static void mpc512x_set_pixel_clock(unsigned int pixclock) { - unsigned long bestval, bestfreq, speed, busfreq; - unsigned long minpixclock, maxpixclock, pixval; - struct mpc512x_ccm __iomem *ccm; struct device_node *np; - u32 temp; - long err; - int i; + struct clk *clk_diu; + unsigned long epsilon, minpixclock, maxpixclock; + unsigned long offset, want, got, delta; - np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-clock"); + /* lookup and enable the DIU clock */ + np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu"); if (!np) { - pr_err("Can't find clock control module.\n"); + pr_err("Could not find DIU device tree node.\n"); return; } - - ccm = of_iomap(np, 0); + clk_diu = of_clk_get(np, 0); + if (IS_ERR(clk_diu)) { + /* backwards compat with device trees that lack clock specs */ + clk_diu = clk_get_sys(np->name, "ipg"); + } of_node_put(np); - if (!ccm) { - pr_err("Can't map clock control module reg.\n"); + if (IS_ERR(clk_diu)) { + pr_err("Could not lookup DIU clock.\n"); return; } - - np = of_find_node_by_type(NULL, "cpu"); - if (np) { - const unsigned int *prop = - of_get_property(np, "bus-frequency", NULL); - - of_node_put(np); - if (prop) { - busfreq = *prop; - } else { - pr_err("Can't get bus-frequency property\n"); - return; - } - } else { - pr_err("Can't find 'cpu' node.\n"); + if (clk_prepare_enable(clk_diu)) { + pr_err("Could not enable DIU clock.\n"); return; } - /* Pixel Clock configuration */ - pr_debug("DIU: Bus Frequency = %lu\n", busfreq); - speed = busfreq * 4; /* DIU_DIV ratio is 4 * CSB_CLK / DIU_CLK */ - - /* Calculate the pixel clock with the smallest error */ - /* calculate the following in steps to avoid overflow */ - pr_debug("DIU pixclock in ps - %d\n", pixclock); - temp = (1000000000 / pixclock) * 1000; - pixclock = temp; - pr_debug("DIU pixclock freq - %u\n", pixclock); - - temp = temp / 20; /* pixclock * 0.05 */ - pr_debug("deviation = %d\n", temp); - minpixclock = pixclock - temp; - maxpixclock = pixclock + temp; - pr_debug("DIU minpixclock - %lu\n", minpixclock); - pr_debug("DIU maxpixclock - %lu\n", maxpixclock); - pixval = speed/pixclock; - pr_debug("DIU pixval = %lu\n", pixval); - - err = LONG_MAX; - bestval = pixval; - pr_debug("DIU bestval = %lu\n", bestval); - - bestfreq = 0; - for (i = -1; i <= 1; i++) { - temp = speed / (pixval+i); - pr_debug("DIU test pixval i=%d, pixval=%lu, temp freq. = %u\n", - i, pixval, temp); - if ((temp < minpixclock) || (temp > maxpixclock)) - pr_debug("DIU exceeds monitor range (%lu to %lu)\n", - minpixclock, maxpixclock); - else if (abs(temp - pixclock) < err) { - pr_debug("Entered the else if block %d\n", i); - err = abs(temp - pixclock); - bestval = pixval + i; - bestfreq = temp; - } + /* + * convert the picoseconds spec into the desired clock rate, + * determine the acceptable clock range for the monitor (+/- 5%), + * do the calculation in steps to avoid integer overflow + */ + pr_debug("DIU pixclock in ps - %u\n", pixclock); + pixclock = (1000000000 / pixclock) * 1000; + pr_debug("DIU pixclock freq - %u\n", pixclock); + epsilon = pixclock / 20; /* pixclock * 0.05 */ + pr_debug("DIU deviation - %lu\n", epsilon); + minpixclock = pixclock - epsilon; + maxpixclock = pixclock + epsilon; + pr_debug("DIU minpixclock - %lu\n", minpixclock); + pr_debug("DIU maxpixclock - %lu\n", maxpixclock); + + /* + * check whether the DIU supports the desired pixel clock + * + * - simply request the desired clock and see what the + * platform's clock driver will make of it, assuming that it + * will setup the best approximation of the requested value + * - try other candidate frequencies in the order of decreasing + * preference (i.e. with increasing distance from the desired + * pixel clock, and checking the lower frequency before the + * higher frequency to not overload the hardware) until the + * first match is found -- any potential subsequent match + * would only be as good as the former match or typically + * would be less preferrable + * + * the offset increment of pixelclock divided by 64 is an + * arbitrary choice -- it's simple to calculate, in the typical + * case we expect the first check to succeed already, in the + * worst case seven frequencies get tested (the exact center and + * three more values each to the left and to the right) before + * the 5% tolerance window is exceeded, resulting in fast enough + * execution yet high enough probability of finding a suitable + * value, while the error rate will be in the order of single + * percents + */ + for (offset = 0; offset <= epsilon; offset += pixclock / 64) { + want = pixclock - offset; + pr_debug("DIU checking clock - %lu\n", want); + clk_set_rate(clk_diu, want); + got = clk_get_rate(clk_diu); + delta = abs(pixclock - got); + if (delta < epsilon) + break; + if (!offset) + continue; + want = pixclock + offset; + pr_debug("DIU checking clock - %lu\n", want); + clk_set_rate(clk_diu, want); + got = clk_get_rate(clk_diu); + delta = abs(pixclock - got); + if (delta < epsilon) + break; } + if (offset <= epsilon) { + pr_debug("DIU clock accepted - %lu\n", want); + pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n", + pixclock, got, delta, epsilon); + return; + } + pr_warn("DIU pixclock auto search unsuccessful\n"); - pr_debug("DIU chose = %lx\n", bestval); - pr_debug("DIU error = %ld\n NomPixClk ", err); - pr_debug("DIU: Best Freq = %lx\n", bestfreq); - /* Modify DIU_DIV in CCM SCFR1 */ - temp = in_be32(&ccm->scfr1); - pr_debug("DIU: Current value of SCFR1: 0x%08x\n", temp); - temp &= ~DIU_DIV_MASK; - temp |= (bestval & DIU_DIV_MASK); - out_be32(&ccm->scfr1, temp); - pr_debug("DIU: Modified value of SCFR1: 0x%08x\n", temp); - iounmap(ccm); + /* + * what is the most appropriate action to take when the search + * for an available pixel clock which is acceptable to the + * monitor has failed? disable the DIU (clock) or just provide + * a "best effort"? we go with the latter + */ + pr_warn("DIU pixclock best effort fallback (backend's choice)\n"); + clk_set_rate(clk_diu, pixclock); + got = clk_get_rate(clk_diu); + delta = abs(pixclock - got); + pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n", + pixclock, got, delta, epsilon); } static enum fsl_diu_monitor_port |