summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/devicetree/bindings/regulator/ti-abb-regulator.txt128
-rw-r--r--drivers/regulator/Kconfig10
-rw-r--r--drivers/regulator/Makefile1
-rw-r--r--drivers/regulator/ti-abb-regulator.c912
4 files changed, 1051 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/regulator/ti-abb-regulator.txt b/Documentation/devicetree/bindings/regulator/ti-abb-regulator.txt
new file mode 100644
index 000000000000..2e57a33e9029
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/ti-abb-regulator.txt
@@ -0,0 +1,128 @@
+Adaptive Body Bias(ABB) SoC internal LDO regulator for Texas Instruments SoCs
+
+Required Properties:
+- compatible: Should be one of:
+ - "ti,abb-v1" for older SoCs like OMAP3
+ - "ti,abb-v2" for newer SoCs like OMAP4, OMAP5
+- reg: Address and length of the register set for the device. It contains
+ the information of registers in the same order as described by reg-names
+- reg-names: Should contain the reg names
+ - "base-address" - contains base address of ABB module
+ - "int-address" - contains address of interrupt register for ABB module
+ (also see Optional properties)
+- #address-cell: should be 0
+- #size-cell: should be 0
+- clocks: should point to the clock node used by ABB module
+- ti,settling-time: Settling time in uSecs from SoC documentation for ABB module
+ to settle down(target time for SR2_WTCNT_VALUE).
+- ti,clock-cycles: SoC specific data about count of system ti,clock-cycles used for
+ computing settling time from SoC Documentation for ABB module(clock
+ cycles for SR2_WTCNT_VALUE).
+- ti,tranxdone-status-mask: Mask to the int-register to write-to-clear mask
+ indicating LDO tranxdone (operation complete).
+- ti,abb_info: An array of 6-tuples u32 items providing information about ABB
+ configuration needed per operational voltage of the device.
+ Each item consists of the following in the same order:
+ volt: voltage in uV - Only used to index ABB information.
+ ABB mode: one of the following:
+ 0-bypass
+ 1-Forward Body Bias(FBB)
+ 3-Reverse Body Bias(RBB)
+ efuse: (see Optional properties)
+ RBB enable efuse Mask: (See Optional properties)
+ FBB enable efuse Mask: (See Optional properties)
+ Vset value efuse Mask: (See Optional properties)
+
+ NOTE: If more than 1 entry is present, then regulator is setup to change
+ voltage, allowing for various modes to be selected indexed off
+ the regulator. Further, ABB LDOs are considered always-on by
+ default.
+
+Optional Properties:
+- reg-names: In addition to the required properties, the following are optional
+ - "efuse-address" - Contains efuse base address used to pick up ABB info.
+ - "ldo-address" - Contains address of ABB LDO overide register address.
+ "efuse-address" is required for this.
+- ti,ldovbb-vset-mask - Required if ldo-address is set, mask for LDO override
+ register to provide override vset value.
+- ti,ldovbb-override-mask - Required if ldo-address is set, mask for LDO
+ override register to enable override vset value.
+- ti,abb_opp_sel: Addendum to the description in required properties
+ efuse: Mandatory if 'efuse-address' register is defined. Provides offset
+ from efuse-address to pick up ABB characteristics. Set to 0 if
+ 'efuse-address' is not defined.
+ RBB enable efuse Mask: Optional if 'efuse-address' register is defined.
+ 'ABB mode' is force set to RBB mode if value at "efuse-address"
+ + efuse maps to RBB mask. Set to 0 to ignore this.
+ FBB enable efuse Mask: Optional if 'efuse-address' register is defined.
+ 'ABB mode' is force set to FBB mode if value at "efuse-address"
+ + efuse maps to FBB mask (valid only if RBB mask does not match)
+ Set to 0 to ignore this.
+ Vset value efuse Mask: Mandatory if ldo-address is set. Picks up from
+ efuse the value to set in 'ti,ldovbb-vset-mask' at ldo-address.
+
+Example #1: Simplest configuration (no efuse data, hard coded ABB table):
+abb_x: regulator-abb-x {
+ compatible = "ti,abb-v1";
+ regulator-name = "abb_x";
+ #address-cell = <0>;
+ #size-cells = <0>;
+ reg = <0x483072f0 0x8>, <0x48306818 0x4>;
+ reg-names = "base-address", "int-address";
+ ti,tranxdone-status-mask = <0x4000000>;
+ clocks = <&sysclk>;
+ ti,settling-time = <30>;
+ ti,clock-cycles = <8>;
+ ti,abb_info = <
+ /* uV ABB efuse rbb_m fbb_m vset_m */
+ 1012500 0 0 0 0 0 /* Bypass */
+ 1200000 3 0 0 0 0 /* RBB mandatory */
+ 1320000 1 0 0 0 0 /* FBB mandatory */
+ >;
+};
+
+Example #2: Efuse bits contain ABB mode setting (no LDO override capability)
+abb_y: regulator-abb-y {
+ compatible = "ti,abb-v2";
+ regulator-name = "abb_y";
+ #address-cell = <0>;
+ #size-cells = <0>;
+ reg = <0x4a307bd0 0x8>, <0x4a306014 0x4>, <0x4A002268 0x8>;
+ reg-names = "base-address", "int-address", "efuse-address";
+ ti,tranxdone-status-mask = <0x4000000>;
+ clocks = <&sysclk>;
+ ti,settling-time = <50>;
+ ti,clock-cycles = <16>;
+ ti,abb_info = <
+ /* uV ABB efuse rbb_m fbb_m vset_m */
+ 975000 0 0 0 0 0 /* Bypass */
+ 1012500 0 0 0x40000 0 0 /* RBB optional */
+ 1200000 0 0x4 0 0x40000 0 /* FBB optional */
+ 1320000 1 0 0 0 0 /* FBB mandatory */
+ >;
+};
+
+Example #3: Efuse bits contain ABB mode setting and LDO override capability
+abb_z: regulator-abb-z {
+ compatible = "ti,abb-v2";
+ regulator-name = "abb_z";
+ #address-cell = <0>;
+ #size-cells = <0>;
+ reg = <0x4ae07ce4 0x8>, <0x4ae06010 0x4>,
+ <0x4a002194 0x8>, <0x4ae0C314 0x4>;
+ reg-names = "base-address", "int-address",
+ "efuse-address", "ldo-address";
+ ti,tranxdone-status-mask = <0x8000000>;
+ /* LDOVBBMM_MUX_CTRL */
+ ti,ldovbb-override-mask = <0x400>;
+ /* LDOVBBMM_VSET_OUT */
+ ti,ldovbb-vset-mask = <0x1F>;
+ clocks = <&sysclk>;
+ ti,settling-time = <50>;
+ ti,clock-cycles = <16>;
+ ti,abb_info = <
+ /* uV ABB efuse rbb_m fbb_m vset_m */
+ 975000 0 0 0 0 0 /* Bypass */
+ 1200000 0 0x4 0 0x40000 0x1f00 /* FBB optional, vset */
+ >;
+};
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 8bb26446037e..9296425103ef 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -472,6 +472,16 @@ config REGULATOR_TWL4030
This driver supports the voltage regulators provided by
this family of companion chips.
+config REGULATOR_TI_ABB
+ bool "TI Adaptive Body Bias on-chip LDO"
+ depends on ARCH_OMAP
+ help
+ Select this option to support Texas Instruments' on-chip Adaptive Body
+ Bias (ABB) LDO regulators. It is recommended that this option be
+ enabled on required TI SoC. Certain Operating Performance Points
+ on TI SoCs may be unstable without enabling this as it provides
+ device specific optimized bias to allow/optimize functionality.
+
config REGULATOR_VEXPRESS
tristate "Versatile Express regulators"
depends on VEXPRESS_CONFIG
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 47a34ff88f98..95350e890973 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o
obj-$(CONFIG_REGULATOR_TPS65912) += tps65912-regulator.o
obj-$(CONFIG_REGULATOR_TPS80031) += tps80031-regulator.o
obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_TI_ABB) += ti-abb-regulator.o
obj-$(CONFIG_REGULATOR_VEXPRESS) += vexpress.o
obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/ti-abb-regulator.c b/drivers/regulator/ti-abb-regulator.c
new file mode 100644
index 000000000000..c1870ea64939
--- /dev/null
+++ b/drivers/regulator/ti-abb-regulator.c
@@ -0,0 +1,912 @@
+/*
+ * Texas Instruments SoC Adaptive Body Bias(ABB) Regulator
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Mike Turquette <mturquette@ti.com>
+ *
+ * Copyright (C) 2012-2013 Texas Instruments, Inc.
+ * Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
+ * Nishanth Menon <nm@ti.com>
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+/*
+ * ABB LDO operating states:
+ * NOMINAL_OPP: bypasses the ABB LDO
+ * FAST_OPP: sets ABB LDO to Forward Body-Bias
+ * SLOW_OPP: sets ABB LDO to Reverse Body-Bias
+ */
+#define TI_ABB_NOMINAL_OPP 0
+#define TI_ABB_FAST_OPP 1
+#define TI_ABB_SLOW_OPP 3
+
+/**
+ * struct ti_abb_info - ABB information per voltage setting
+ * @opp_sel: one of TI_ABB macro
+ * @vset: (optional) vset value that LDOVBB needs to be overriden with.
+ *
+ * Array of per voltage entries organized in the same order as regulator_desc's
+ * volt_table list. (selector is used to index from this array)
+ */
+struct ti_abb_info {
+ u32 opp_sel;
+ u32 vset;
+};
+
+/**
+ * struct ti_abb_reg - Register description for ABB block
+ * @setup_reg: setup register offset from base
+ * @control_reg: control register offset from base
+ * @sr2_wtcnt_value_mask: setup register- sr2_wtcnt_value mask
+ * @fbb_sel_mask: setup register- FBB sel mask
+ * @rbb_sel_mask: setup register- RBB sel mask
+ * @sr2_en_mask: setup register- enable mask
+ * @opp_change_mask: control register - mask to trigger LDOVBB change
+ * @opp_sel_mask: control register - mask for mode to operate
+ */
+struct ti_abb_reg {
+ u32 setup_reg;
+ u32 control_reg;
+
+ /* Setup register fields */
+ u32 sr2_wtcnt_value_mask;
+ u32 fbb_sel_mask;
+ u32 rbb_sel_mask;
+ u32 sr2_en_mask;
+
+ /* Control register fields */
+ u32 opp_change_mask;
+ u32 opp_sel_mask;
+};
+
+/**
+ * struct ti_abb - ABB instance data
+ * @rdesc: regulator descriptor
+ * @clk: clock(usually sysclk) supplying ABB block
+ * @base: base address of ABB block
+ * @int_base: interrupt register base address
+ * @efuse_base: (optional) efuse base address for ABB modes
+ * @ldo_base: (optional) LDOVBB vset override base address
+ * @regs: pointer to struct ti_abb_reg for ABB block
+ * @txdone_mask: mask on int_base for tranxdone interrupt
+ * @ldovbb_override_mask: mask to ldo_base for overriding default LDO VBB
+ * vset with value from efuse
+ * @ldovbb_vset_mask: mask to ldo_base for providing the VSET override
+ * @info: array to per voltage ABB configuration
+ * @current_info_idx: current index to info
+ * @settling_time: SoC specific settling time for LDO VBB
+ */
+struct ti_abb {
+ struct regulator_desc rdesc;
+ struct clk *clk;
+ void __iomem *base;
+ void __iomem *int_base;
+ void __iomem *efuse_base;
+ void __iomem *ldo_base;
+
+ const struct ti_abb_reg *regs;
+ u32 txdone_mask;
+ u32 ldovbb_override_mask;
+ u32 ldovbb_vset_mask;
+
+ struct ti_abb_info *info;
+ int current_info_idx;
+
+ u32 settling_time;
+};
+
+/**
+ * ti_abb_rmw() - handy wrapper to set specific register bits
+ * @mask: mask for register field
+ * @value: value shifted to mask location and written
+ * @offset: offset of register
+ * @base: base address
+ *
+ * Return: final register value (may be unused)
+ */
+static inline u32 ti_abb_rmw(u32 mask, u32 value, u32 offset,
+ void __iomem *base)
+{
+ u32 val;
+
+ val = readl(base + offset);
+ val &= ~mask;
+ val |= (value << __ffs(mask)) & mask;
+ writel(val, base + offset);
+
+ return val;
+}
+
+/**
+ * ti_abb_check_txdone() - handy wrapper to check ABB tranxdone status
+ * @abb: pointer to the abb instance
+ *
+ * Return: true or false
+ */
+static inline bool ti_abb_check_txdone(const struct ti_abb *abb)
+{
+ return !!(readl(abb->int_base) & abb->txdone_mask);
+}
+
+/**
+ * ti_abb_clear_txdone() - handy wrapper to clear ABB tranxdone status
+ * @abb: pointer to the abb instance
+ */
+static inline void ti_abb_clear_txdone(const struct ti_abb *abb)
+{
+ writel(abb->txdone_mask, abb->int_base);
+};
+
+/**
+ * ti_abb_wait_tranx() - waits for ABB tranxdone event
+ * @dev: device
+ * @abb: pointer to the abb instance
+ *
+ * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
+ */
+static int ti_abb_wait_txdone(struct device *dev, struct ti_abb *abb)
+{
+ int timeout = 0;
+ bool status;
+
+ while (timeout++ <= abb->settling_time) {
+ status = ti_abb_check_txdone(abb);
+ if (status)
+ break;
+
+ udelay(1);
+ }
+
+ if (timeout > abb->settling_time) {
+ dev_warn_ratelimited(dev,
+ "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
+ __func__, timeout, readl(abb->int_base));
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/**
+ * ti_abb_clear_all_txdone() - clears ABB tranxdone event
+ * @dev: device
+ * @abb: pointer to the abb instance
+ *
+ * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
+ */
+static int ti_abb_clear_all_txdone(struct device *dev, const struct ti_abb *abb)
+{
+ int timeout = 0;
+ bool status;
+
+ while (timeout++ <= abb->settling_time) {
+ ti_abb_clear_txdone(abb);
+
+ status = ti_abb_check_txdone(abb);
+ if (!status)
+ break;
+
+ udelay(1);
+ }
+
+ if (timeout > abb->settling_time) {
+ dev_warn_ratelimited(dev,
+ "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
+ __func__, timeout, readl(abb->int_base));
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/**
+ * ti_abb_program_ldovbb() - program LDOVBB register for override value
+ * @dev: device
+ * @abb: pointer to the abb instance
+ * @info: ABB info to program
+ */
+static void ti_abb_program_ldovbb(struct device *dev, const struct ti_abb *abb,
+ struct ti_abb_info *info)
+{
+ u32 val;
+
+ val = readl(abb->ldo_base);
+ /* clear up previous values */
+ val &= ~(abb->ldovbb_override_mask | abb->ldovbb_vset_mask);
+
+ switch (info->opp_sel) {
+ case TI_ABB_SLOW_OPP:
+ case TI_ABB_FAST_OPP:
+ val |= abb->ldovbb_override_mask;
+ val |= info->vset << __ffs(abb->ldovbb_vset_mask);
+ break;
+ }
+
+ writel(val, abb->ldo_base);
+}
+
+/**
+ * ti_abb_set_opp() - Setup ABB and LDO VBB for required bias
+ * @rdev: regulator device
+ * @abb: pointer to the abb instance
+ * @info: ABB info to program
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_set_opp(struct regulator_dev *rdev, struct ti_abb *abb,
+ struct ti_abb_info *info)
+{
+ const struct ti_abb_reg *regs = abb->regs;
+ struct device *dev = &rdev->dev;
+ int ret;
+
+ ret = ti_abb_clear_all_txdone(dev, abb);
+ if (ret)
+ goto out;
+
+ ti_abb_rmw(regs->fbb_sel_mask | regs->rbb_sel_mask, 0, regs->setup_reg,
+ abb->base);
+
+ switch (info->opp_sel) {
+ case TI_ABB_SLOW_OPP:
+ ti_abb_rmw(regs->rbb_sel_mask, 1, regs->setup_reg, abb->base);
+ break;
+ case TI_ABB_FAST_OPP:
+ ti_abb_rmw(regs->fbb_sel_mask, 1, regs->setup_reg, abb->base);
+ break;
+ }
+
+ /* program next state of ABB ldo */
+ ti_abb_rmw(regs->opp_sel_mask, info->opp_sel, regs->control_reg,
+ abb->base);
+
+ /* program LDO VBB vset override if needed */
+ if (abb->ldo_base)
+ ti_abb_program_ldovbb(dev, abb, info);
+
+ /* Initiate ABB ldo change */
+ ti_abb_rmw(regs->opp_change_mask, 1, regs->control_reg, abb->base);
+
+ /* Wait for ABB LDO to complete transition to new Bias setting */
+ ret = ti_abb_wait_txdone(dev, abb);
+ if (ret)
+ goto out;
+
+ ret = ti_abb_clear_all_txdone(dev, abb);
+ if (ret)
+ goto out;
+
+out:
+ return ret;
+}
+
+/**
+ * ti_abb_set_voltage_sel() - regulator accessor function to set ABB LDO
+ * @rdev: regulator device
+ * @sel: selector to index into required ABB LDO settings (maps to
+ * regulator descriptor's volt_table)
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_set_voltage_sel(struct regulator_dev *rdev, unsigned sel)
+{
+ const struct regulator_desc *desc = rdev->desc;
+ struct ti_abb *abb = rdev_get_drvdata(rdev);
+ struct device *dev = &rdev->dev;
+ struct ti_abb_info *info, *oinfo;
+ int ret = 0;
+
+ if (!abb) {
+ dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ if (!desc->n_voltages || !abb->info) {
+ dev_err_ratelimited(dev,
+ "%s: No valid voltage table entries?\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ if (sel >= desc->n_voltages) {
+ dev_err(dev, "%s: sel idx(%d) >= n_voltages(%d)\n", __func__,
+ sel, desc->n_voltages);
+ return -EINVAL;
+ }
+
+ /* If we are in the same index as we were, nothing to do here! */
+ if (sel == abb->current_info_idx) {
+ dev_dbg(dev, "%s: Already at sel=%d\n", __func__, sel);
+ return ret;
+ }
+
+ /* If data is exactly the same, then just update index, no change */
+ info = &abb->info[sel];
+ oinfo = &abb->info[abb->current_info_idx];
+ if (!memcmp(info, oinfo, sizeof(*info))) {
+ dev_dbg(dev, "%s: Same data new idx=%d, old idx=%d\n", __func__,
+ sel, abb->current_info_idx);
+ goto out;
+ }
+
+ ret = ti_abb_set_opp(rdev, abb, info);
+
+out:
+ if (!ret)
+ abb->current_info_idx = sel;
+ else
+ dev_err_ratelimited(dev,
+ "%s: Volt[%d] idx[%d] mode[%d] Fail(%d)\n",
+ __func__, desc->volt_table[sel], sel,
+ info->opp_sel, ret);
+ return ret;
+}
+
+/**
+ * ti_abb_get_voltage_sel() - Regulator accessor to get current ABB LDO setting
+ * @rdev: regulator device
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_get_voltage_sel(struct regulator_dev *rdev)
+{
+ const struct regulator_desc *desc = rdev->desc;
+ struct ti_abb *abb = rdev_get_drvdata(rdev);
+ struct device *dev = &rdev->dev;
+
+ if (!abb) {
+ dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ if (!desc->n_voltages || !abb->info) {
+ dev_err_ratelimited(dev,
+ "%s: No valid voltage table entries?\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ if (abb->current_info_idx > (int)desc->n_voltages) {
+ dev_err(dev, "%s: Corrupted data? idx(%d) > n_voltages(%d)\n",
+ __func__, abb->current_info_idx, desc->n_voltages);
+ return -EINVAL;
+ }
+
+ return abb->current_info_idx;
+}
+
+/**
+ * ti_abb_init_timings() - setup ABB clock timing for the current platform
+ * @dev: device
+ * @abb: pointer to the abb instance
+ *
+ * Return: 0 if timing is updated, else returns error result.
+ */
+static int ti_abb_init_timings(struct device *dev, struct ti_abb *abb)
+{
+ u32 clock_cycles;
+ u32 clk_rate, sr2_wt_cnt_val, cycle_rate;
+ const struct ti_abb_reg *regs = abb->regs;
+ int ret;
+ char *pname = "ti,settling-time";
+
+ /* read device tree properties */
+ ret = of_property_read_u32(dev->of_node, pname, &abb->settling_time);
+ if (ret) {
+ dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
+ return ret;
+ }
+
+ /* ABB LDO cannot be settle in 0 time */
+ if (!abb->settling_time) {
+ dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+ return -EINVAL;
+ }
+
+ pname = "ti,clock-cycles";
+ ret = of_property_read_u32(dev->of_node, pname, &clock_cycles);
+ if (ret) {
+ dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
+ return ret;
+ }
+ /* ABB LDO cannot be settle in 0 clock cycles */
+ if (!clock_cycles) {
+ dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+ return -EINVAL;
+ }
+
+ abb->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(abb->clk)) {
+ ret = PTR_ERR(abb->clk);
+ dev_err(dev, "%s: Unable to get clk(%d)\n", __func__, ret);
+ return ret;
+ }
+
+ /*
+ * SR2_WTCNT_VALUE is the settling time for the ABB ldo after a
+ * transition and must be programmed with the correct time at boot.
+ * The value programmed into the register is the number of SYS_CLK
+ * clock cycles that match a given wall time profiled for the ldo.
+ * This value depends on:
+ * settling time of ldo in micro-seconds (varies per OMAP family)
+ * # of clock cycles per SYS_CLK period (varies per OMAP family)
+ * the SYS_CLK frequency in MHz (varies per board)
+ * The formula is:
+ *
+ * ldo settling time (in micro-seconds)
+ * SR2_WTCNT_VALUE = ------------------------------------------
+ * (# system clock cycles) * (sys_clk period)
+ *
+ * Put another way:
+ *
+ * SR2_WTCNT_VALUE = settling time / (# SYS_CLK cycles / SYS_CLK rate))
+ *
+ * To avoid dividing by zero multiply both "# clock cycles" and
+ * "settling time" by 10 such that the final result is the one we want.
+ */
+
+ /* Convert SYS_CLK rate to MHz & prevent divide by zero */
+ clk_rate = DIV_ROUND_CLOSEST(clk_get_rate(abb->clk), 1000000);
+
+ /* Calculate cycle rate */
+ cycle_rate = DIV_ROUND_CLOSEST(clock_cycles * 10, clk_rate);
+
+ /* Calulate SR2_WTCNT_VALUE */
+ sr2_wt_cnt_val = DIV_ROUND_CLOSEST(abb->settling_time * 10, cycle_rate);
+
+ dev_dbg(dev, "%s: Clk_rate=%ld, sr2_cnt=0x%08x\n", __func__,
+ clk_get_rate(abb->clk), sr2_wt_cnt_val);
+
+ ti_abb_rmw(regs->sr2_wtcnt_value_mask, sr2_wt_cnt_val, regs->setup_reg,
+ abb->base);
+
+ return 0;
+}
+
+/**
+ * ti_abb_init_table() - Initialize ABB table from device tree
+ * @dev: device
+ * @abb: pointer to the abb instance
+ * @rinit_data: regulator initdata
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_init_table(struct device *dev, struct ti_abb *abb,
+ struct regulator_init_data *rinit_data)
+{
+ struct ti_abb_info *info;
+ const struct property *prop;
+ const __be32 *abb_info;
+ const u32 num_values = 6;
+ char *pname = "ti,abb_info";
+ u32 num_entries, i;
+ unsigned int *volt_table;
+ int min_uV = INT_MAX, max_uV = 0;
+ struct regulation_constraints *c = &rinit_data->constraints;
+
+ prop = of_find_property(dev->of_node, pname, NULL);
+ if (!prop) {
+ dev_err(dev, "No '%s' property?\n", pname);
+ return -ENODEV;
+ }
+
+ if (!prop->value) {
+ dev_err(dev, "Empty '%s' property?\n", pname);
+ return -ENODATA;
+ }
+
+ /*
+ * Each abb_info is a set of n-tuple, where n is num_values, consisting
+ * of voltage and a set of detection logic for ABB information for that
+ * voltage to apply.
+ */
+ num_entries = prop->length / sizeof(u32);
+ if (!num_entries || (num_entries % num_values)) {
+ dev_err(dev, "All '%s' list entries need %d vals\n", pname,
+ num_values);
+ return -EINVAL;
+ }
+ num_entries /= num_values;
+
+ info = devm_kzalloc(dev, sizeof(*info) * num_entries, GFP_KERNEL);
+ if (!info) {
+ dev_err(dev, "Can't allocate info table for '%s' property\n",
+ pname);
+ return -ENOMEM;
+ }
+ abb->info = info;
+
+ volt_table = devm_kzalloc(dev, sizeof(unsigned int) * num_entries,
+ GFP_KERNEL);
+ if (!volt_table) {
+ dev_err(dev, "Can't allocate voltage table for '%s' property\n",
+ pname);
+ return -ENOMEM;
+ }
+
+ abb->rdesc.n_voltages = num_entries;
+ abb->rdesc.volt_table = volt_table;
+ /* We do not know where the OPP voltage is at the moment */
+ abb->current_info_idx = -EINVAL;
+
+ abb_info = prop->value;
+ for (i = 0; i < num_entries; i++, info++, volt_table++) {
+ u32 efuse_offset, rbb_mask, fbb_mask, vset_mask;
+ u32 efuse_val;
+
+ /* NOTE: num_values should equal to entries picked up here */
+ *volt_table = be32_to_cpup(abb_info++);
+ info->opp_sel = be32_to_cpup(abb_info++);
+ efuse_offset = be32_to_cpup(abb_info++);
+ rbb_mask = be32_to_cpup(abb_info++);
+ fbb_mask = be32_to_cpup(abb_info++);
+ vset_mask = be32_to_cpup(abb_info++);
+
+ dev_dbg(dev,
+ "[%d]v=%d ABB=%d ef=0x%x rbb=0x%x fbb=0x%x vset=0x%x\n",
+ i, *volt_table, info->opp_sel, efuse_offset, rbb_mask,
+ fbb_mask, vset_mask);
+
+ /* Find min/max for voltage set */
+ if (min_uV > *volt_table)
+ min_uV = *volt_table;
+ if (max_uV < *volt_table)
+ max_uV = *volt_table;
+
+ if (!abb->efuse_base) {
+ /* Ignore invalid data, but warn to help cleanup */
+ if (efuse_offset || rbb_mask || fbb_mask || vset_mask)
+ dev_err(dev, "prop '%s': v=%d,bad efuse/mask\n",
+ pname, *volt_table);
+ goto check_abb;
+ }
+
+ efuse_val = readl(abb->efuse_base + efuse_offset);
+
+ /* Use ABB recommendation from Efuse */
+ if (efuse_val & rbb_mask)
+ info->opp_sel = TI_ABB_SLOW_OPP;
+ else if (efuse_val & fbb_mask)
+ info->opp_sel = TI_ABB_FAST_OPP;
+ else if (rbb_mask || fbb_mask)
+ info->opp_sel = TI_ABB_NOMINAL_OPP;
+
+ dev_dbg(dev,
+ "[%d]v=%d efusev=0x%x final ABB=%d\n",
+ i, *volt_table, efuse_val, info->opp_sel);
+
+ /* Use recommended Vset bits from Efuse */
+ if (!abb->ldo_base) {
+ if (vset_mask)
+ dev_err(dev, "prop'%s':v=%d vst=%x LDO base?\n",
+ pname, *volt_table, vset_mask);
+ continue;
+ }
+ info->vset = efuse_val & vset_mask >> __ffs(vset_mask);
+ dev_dbg(dev, "[%d]v=%d vset=%x\n", i, *volt_table, info->vset);
+check_abb:
+ switch (info->opp_sel) {
+ case TI_ABB_NOMINAL_OPP:
+ case TI_ABB_FAST_OPP:
+ case TI_ABB_SLOW_OPP:
+ /* Valid values */
+ break;
+ default:
+ dev_err(dev, "%s:[%d]v=%d, ABB=%d is invalid! Abort!\n",
+ __func__, i, *volt_table, info->opp_sel);
+ return -EINVAL;
+ }
+ }
+
+ /* Setup the min/max voltage constraints from the supported list */
+ c->min_uV = min_uV;
+ c->max_uV = max_uV;
+
+ return 0;
+}
+
+static struct regulator_ops ti_abb_reg_ops = {
+ .list_voltage = regulator_list_voltage_table,
+
+ .set_voltage_sel = ti_abb_set_voltage_sel,
+ .get_voltage_sel = ti_abb_get_voltage_sel,
+};
+
+/* Default ABB block offsets, IF this changes in future, create new one */
+static const struct ti_abb_reg abb_regs_v1 = {
+ /* WARNING: registers are wrongly documented in TRM */
+ .setup_reg = 0x04,
+ .control_reg = 0x00,
+
+ .sr2_wtcnt_value_mask = (0xff << 8),
+ .fbb_sel_mask = (0x01 << 2),
+ .rbb_sel_mask = (0x01 << 1),
+ .sr2_en_mask = (0x01 << 0),
+
+ .opp_change_mask = (0x01 << 2),
+ .opp_sel_mask = (0x03 << 0),
+};
+
+static const struct ti_abb_reg abb_regs_v2 = {
+ .setup_reg = 0x00,
+ .control_reg = 0x04,
+
+ .sr2_wtcnt_value_mask = (0xff << 8),
+ .fbb_sel_mask = (0x01 << 2),
+ .rbb_sel_mask = (0x01 << 1),
+ .sr2_en_mask = (0x01 << 0),
+
+ .opp_change_mask = (0x01 << 2),
+ .opp_sel_mask = (0x03 << 0),
+};
+
+static const struct of_device_id ti_abb_of_match[] = {
+ {.compatible = "ti,abb-v1", .data = &abb_regs_v1},
+ {.compatible = "ti,abb-v2", .data = &abb_regs_v2},
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, ti_abb_of_match);
+
+/**
+ * ti_abb_probe() - Initialize an ABB ldo instance
+ * @pdev: ABB platform device
+ *
+ * Initializes an individual ABB LDO for required Body-Bias. ABB is used to
+ * addional bias supply to SoC modules for power savings or mandatory stability
+ * configuration at certain Operating Performance Points(OPPs).
+ *
+ * Return: 0 on success or appropriate error value when fails
+ */
+static int ti_abb_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct of_device_id *match;
+ struct resource *res;
+ struct ti_abb *abb;
+ struct regulator_init_data *initdata = NULL;
+ struct regulator_dev *rdev = NULL;
+ struct regulator_desc *desc;
+ struct regulation_constraints *c;
+ struct regulator_config config = { };
+ char *pname;
+ int ret = 0;
+
+ match = of_match_device(ti_abb_of_match, dev);
+ if (!match) {
+ /* We do not expect this to happen */
+ ret = -ENODEV;
+ dev_err(dev, "%s: Unable to match device\n", __func__);
+ goto err;
+ }
+ if (!match->data) {
+ ret = -EINVAL;
+ dev_err(dev, "%s: Bad data in match\n", __func__);
+ goto err;
+ }
+
+ abb = devm_kzalloc(dev, sizeof(struct ti_abb), GFP_KERNEL);
+ if (!abb) {
+ dev_err(dev, "%s: Unable to allocate ABB struct\n", __func__);
+ ret = -ENOMEM;
+ goto err;
+ }
+ abb->regs = match->data;
+
+ /* Map ABB resources */
+ pname = "base-address";
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+ if (!res) {
+ dev_err(dev, "Missing '%s' IO resource\n", pname);
+ ret = -ENODEV;
+ goto err;
+ }
+ abb->base = devm_request_and_ioremap(dev, res);
+ if (!abb->base) {
+ dev_err(dev, "Unable to map '%s'\n", pname);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ pname = "int-address";
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+ if (!res) {
+ dev_err(dev, "Missing '%s' IO resource\n", pname);
+ ret = -ENODEV;
+ goto err;
+ }
+ /*
+ * We may have shared interrupt register offsets which are
+ * write-1-to-clear between domains ensuring exclusivity.
+ */
+ abb->int_base = devm_ioremap_nocache(dev, res->start,
+ resource_size(res));
+ if (!abb->int_base) {
+ dev_err(dev, "Unable to map '%s'\n", pname);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ /* Map Optional resources */
+ pname = "efuse-address";
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+ if (!res) {
+ dev_dbg(dev, "Missing '%s' IO resource\n", pname);
+ ret = -ENODEV;
+ goto skip_opt;
+ }
+
+ /*
+ * We may have shared efuse register offsets which are read-only
+ * between domains
+ */
+ abb->efuse_base = devm_ioremap_nocache(dev, res->start,
+ resource_size(res));
+ if (!abb->efuse_base) {
+ dev_err(dev, "Unable to map '%s'\n", pname);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ pname = "ldo-address";
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+ if (!res) {
+ dev_dbg(dev, "Missing '%s' IO resource\n", pname);
+ ret = -ENODEV;
+ goto skip_opt;
+ }
+ abb->ldo_base = devm_request_and_ioremap(dev, res);
+ if (!abb->ldo_base) {
+ dev_err(dev, "Unable to map '%s'\n", pname);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ /* IF ldo_base is set, the following are mandatory */
+ pname = "ti,ldovbb-override-mask";
+ ret =
+ of_property_read_u32(pdev->dev.of_node, pname,
+ &abb->ldovbb_override_mask);
+ if (ret) {
+ dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+ goto err;
+ }
+ if (!abb->ldovbb_override_mask) {
+ dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ pname = "ti,ldovbb-vset-mask";
+ ret =
+ of_property_read_u32(pdev->dev.of_node, pname,
+ &abb->ldovbb_vset_mask);
+ if (ret) {
+ dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+ goto err;
+ }
+ if (!abb->ldovbb_vset_mask) {
+ dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+ ret = -EINVAL;
+ goto err;
+ }
+
+skip_opt:
+ pname = "ti,tranxdone-status-mask";
+ ret =
+ of_property_read_u32(pdev->dev.of_node, pname,
+ &abb->txdone_mask);
+ if (ret) {
+ dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
+ goto err;
+ }
+ if (!abb->txdone_mask) {
+ dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ initdata = of_get_regulator_init_data(dev, pdev->dev.of_node);
+ if (!initdata) {
+ ret = -ENOMEM;
+ dev_err(dev, "%s: Unable to alloc regulator init data\n",
+ __func__);
+ goto err;
+ }
+
+ /* init ABB opp_sel table */
+ ret = ti_abb_init_table(dev, abb, initdata);
+ if (ret)
+ goto err;
+
+ /* init ABB timing */
+ ret = ti_abb_init_timings(dev, abb);
+ if (ret)
+ goto err;
+
+ desc = &abb->rdesc;
+ desc->name = dev_name(dev);
+ desc->owner = THIS_MODULE;
+ desc->type = REGULATOR_VOLTAGE;
+ desc->ops = &ti_abb_reg_ops;
+
+ c = &initdata->constraints;
+ if (desc->n_voltages > 1)
+ c->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
+ c->always_on = true;
+
+ config.dev = dev;
+ config.init_data = initdata;
+ config.driver_data = abb;
+ config.of_node = pdev->dev.of_node;
+
+ rdev = regulator_register(desc, &config);
+ if (IS_ERR(rdev)) {
+ ret = PTR_ERR(rdev);
+ dev_err(dev, "%s: failed to register regulator(%d)\n",
+ __func__, ret);
+ goto err;
+ }
+ platform_set_drvdata(pdev, rdev);
+
+ /* Enable the ldo if not already done by bootloader */
+ ti_abb_rmw(abb->regs->sr2_en_mask, 1, abb->regs->setup_reg, abb->base);
+
+ return 0;
+
+err:
+ dev_err(dev, "%s: Failed to initialize(%d)\n", __func__, ret);
+ return ret;
+}
+
+/**
+ * ti_abb_remove() - cleanups
+ * @pdev: ABB platform device
+ *
+ * Return: 0
+ */
+static int ti_abb_remove(struct platform_device *pdev)
+{
+ struct regulator_dev *rdev = platform_get_drvdata(pdev);
+
+ regulator_unregister(rdev);
+ return 0;
+}
+
+MODULE_ALIAS("platform:ti_abb");
+
+static struct platform_driver ti_abb_driver = {
+ .probe = ti_abb_probe,
+ .remove = ti_abb_remove,
+ .driver = {
+ .name = "ti_abb",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(ti_abb_of_match),
+ },
+};
+module_platform_driver(ti_abb_driver);
+
+MODULE_DESCRIPTION("Texas Instruments ABB LDO regulator driver");
+MODULE_AUTHOR("Texas Instruments Inc.");
+MODULE_LICENSE("GPL v2");