diff options
Diffstat (limited to 'drivers/ata/pata_at91.c')
| -rw-r--r-- | drivers/ata/pata_at91.c | 285 |
1 files changed, 200 insertions, 85 deletions
diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c index 0da0dcc7dd08..960c72571395 100644 --- a/drivers/ata/pata_at91.c +++ b/drivers/ata/pata_at91.c @@ -3,6 +3,7 @@ * with CompactFlash interface in True IDE mode * * Copyright (C) 2009 Matyukevich Sergey + * 2011 Igor Plyatov * * Based on: * * generic platform driver by Paul Mundt: drivers/ata/pata_platform.c @@ -31,26 +32,149 @@ #include <mach/board.h> #include <mach/gpio.h> +#define DRV_NAME "pata_at91" +#define DRV_VERSION "0.3" -#define DRV_NAME "pata_at91" -#define DRV_VERSION "0.1" - -#define CF_IDE_OFFSET 0x00c00000 -#define CF_ALT_IDE_OFFSET 0x00e00000 -#define CF_IDE_RES_SIZE 0x08 +#define CF_IDE_OFFSET 0x00c00000 +#define CF_ALT_IDE_OFFSET 0x00e00000 +#define CF_IDE_RES_SIZE 0x08 +#define CS_PULSE_MAXIMUM 319 +#define ER_SMC_CALC 1 +#define ER_SMC_RECALC 2 struct at91_ide_info { unsigned long mode; unsigned int cs; - struct clk *mck; - void __iomem *ide_addr; void __iomem *alt_addr; }; -static const struct ata_timing initial_timing = - {XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0}; +/** + * struct smc_range - range of valid values for SMC register. + */ +struct smc_range { + int min; + int max; +}; + +/** + * adjust_smc_value - adjust value for one of SMC registers. + * @value: adjusted value + * @range: array of SMC ranges with valid values + * @size: SMC ranges array size + * + * This returns the difference between input and output value or negative + * in case of invalid input value. + * If negative returned, then output value = maximal possible from ranges. + */ +static int adjust_smc_value(int *value, struct smc_range *range, int size) +{ + int maximum = (range + size - 1)->max; + int remainder; + + do { + if (*value < range->min) { + remainder = range->min - *value; + *value = range->min; /* nearest valid value */ + return remainder; + } else if ((range->min <= *value) && (*value <= range->max)) + return 0; + + range++; + } while (--size); + *value = maximum; + + return -1; /* invalid value */ +} + +/** + * calc_smc_vals - calculate SMC register values + * @dev: ATA device + * @setup: SMC_SETUP register value + * @pulse: SMC_PULSE register value + * @cycle: SMC_CYCLE register value + * + * This returns negative in case of invalid values for SMC registers: + * -ER_SMC_RECALC - recalculation required for SMC values, + * -ER_SMC_CALC - calculation failed (invalid input values). + * + * SMC use special coding scheme, see "Coding and Range of Timing + * Parameters" table from AT91SAM9 datasheets. + * + * SMC_SETUP = 128*setup[5] + setup[4:0] + * SMC_PULSE = 256*pulse[6] + pulse[5:0] + * SMC_CYCLE = 256*cycle[8:7] + cycle[6:0] + */ +static int calc_smc_vals(struct device *dev, + int *setup, int *pulse, int *cycle, int *cs_pulse) +{ + int ret_val; + int err = 0; + struct smc_range range_setup[] = { /* SMC_SETUP valid values */ + {.min = 0, .max = 31}, /* first range */ + {.min = 128, .max = 159} /* second range */ + }; + struct smc_range range_pulse[] = { /* SMC_PULSE valid values */ + {.min = 0, .max = 63}, /* first range */ + {.min = 256, .max = 319} /* second range */ + }; + struct smc_range range_cycle[] = { /* SMC_CYCLE valid values */ + {.min = 0, .max = 127}, /* first range */ + {.min = 256, .max = 383}, /* second range */ + {.min = 512, .max = 639}, /* third range */ + {.min = 768, .max = 895} /* fourth range */ + }; + + ret_val = adjust_smc_value(setup, range_setup, ARRAY_SIZE(range_setup)); + if (ret_val < 0) + dev_warn(dev, "maximal SMC Setup value\n"); + else + *cycle += ret_val; + + ret_val = adjust_smc_value(pulse, range_pulse, ARRAY_SIZE(range_pulse)); + if (ret_val < 0) + dev_warn(dev, "maximal SMC Pulse value\n"); + else + *cycle += ret_val; + + ret_val = adjust_smc_value(cycle, range_cycle, ARRAY_SIZE(range_cycle)); + if (ret_val < 0) + dev_warn(dev, "maximal SMC Cycle value\n"); + + *cs_pulse = *cycle; + if (*cs_pulse > CS_PULSE_MAXIMUM) { + dev_err(dev, "unable to calculate valid SMC settings\n"); + return -ER_SMC_CALC; + } + + ret_val = adjust_smc_value(cs_pulse, range_pulse, + ARRAY_SIZE(range_pulse)); + if (ret_val < 0) { + dev_warn(dev, "maximal SMC CS Pulse value\n"); + } else if (ret_val != 0) { + *cycle = *cs_pulse; + dev_warn(dev, "SMC Cycle extended\n"); + err = -ER_SMC_RECALC; + } + + return err; +} + +/** + * to_smc_format - convert values into SMC format + * @setup: SETUP value of SMC Setup Register + * @pulse: PULSE value of SMC Pulse Register + * @cycle: CYCLE value of SMC Cycle Register + * @cs_pulse: NCS_PULSE value of SMC Pulse Register + */ +static void to_smc_format(int *setup, int *pulse, int *cycle, int *cs_pulse) +{ + *setup = (*setup & 0x1f) | ((*setup & 0x80) >> 2); + *pulse = (*pulse & 0x3f) | ((*pulse & 0x100) >> 2); + *cycle = (*cycle & 0x7f) | ((*cycle & 0x300) >> 1); + *cs_pulse = (*cs_pulse & 0x3f) | ((*cs_pulse & 0x100) >> 2); +} static unsigned long calc_mck_cycles(unsigned long ns, unsigned long mck_hz) { @@ -69,80 +193,77 @@ static unsigned long calc_mck_cycles(unsigned long ns, unsigned long mck_hz) return (ns * mul + 65536) >> 16; /* rounding */ } -static void set_smc_mode(struct at91_ide_info *info) -{ - at91_sys_write(AT91_SMC_MODE(info->cs), info->mode); - return; -} - -static void set_smc_timing(struct device *dev, +/** + * set_smc_timing - SMC timings setup. + * @dev: device + * @info: AT91 IDE info + * @ata: ATA timings + * + * Its assumed that write timings are same as read timings, + * cs_setup = 0 and cs_pulse = cycle. + */ +static void set_smc_timing(struct device *dev, struct ata_device *adev, struct at91_ide_info *info, const struct ata_timing *ata) { - unsigned long read_cycle, write_cycle, active, recover; - unsigned long nrd_setup, nrd_pulse, nrd_recover; - unsigned long nwe_setup, nwe_pulse; - - unsigned long ncs_write_setup, ncs_write_pulse; - unsigned long ncs_read_setup, ncs_read_pulse; - - unsigned long mck_hz; - - read_cycle = ata->cyc8b; - nrd_setup = ata->setup; - nrd_pulse = ata->act8b; - nrd_recover = ata->rec8b; - + int ret = 0; + int use_iordy; + unsigned int t6z; /* data tristate time in ns */ + unsigned int cycle; /* SMC Cycle width in MCK ticks */ + unsigned int setup; /* SMC Setup width in MCK ticks */ + unsigned int pulse; /* CFIOR and CFIOW pulse width in MCK ticks */ + unsigned int cs_setup = 0;/* CS4 or CS5 setup width in MCK ticks */ + unsigned int cs_pulse; /* CS4 or CS5 pulse width in MCK ticks*/ + unsigned int tdf_cycles; /* SMC TDF MCK ticks */ + unsigned long mck_hz; /* MCK frequency in Hz */ + + t6z = (ata->mode < XFER_PIO_5) ? 30 : 20; mck_hz = clk_get_rate(info->mck); + cycle = calc_mck_cycles(ata->cyc8b, mck_hz); + setup = calc_mck_cycles(ata->setup, mck_hz); + pulse = calc_mck_cycles(ata->act8b, mck_hz); + tdf_cycles = calc_mck_cycles(t6z, mck_hz); + + do { + ret = calc_smc_vals(dev, &setup, &pulse, &cycle, &cs_pulse); + } while (ret == -ER_SMC_RECALC); + + if (ret == -ER_SMC_CALC) + dev_err(dev, "Interface may not operate correctly\n"); + + dev_dbg(dev, "SMC Setup=%u, Pulse=%u, Cycle=%u, CS Pulse=%u\n", + setup, pulse, cycle, cs_pulse); + to_smc_format(&setup, &pulse, &cycle, &cs_pulse); + /* disable or enable waiting for IORDY signal */ + use_iordy = ata_pio_need_iordy(adev); + if (use_iordy) + info->mode |= AT91_SMC_EXNWMODE_READY; + + if (tdf_cycles > 15) { + tdf_cycles = 15; + dev_warn(dev, "maximal SMC TDF Cycles value\n"); + } - read_cycle = calc_mck_cycles(read_cycle, mck_hz); - nrd_setup = calc_mck_cycles(nrd_setup, mck_hz); - nrd_pulse = calc_mck_cycles(nrd_pulse, mck_hz); - nrd_recover = calc_mck_cycles(nrd_recover, mck_hz); - - active = nrd_setup + nrd_pulse; - recover = read_cycle - active; - - /* Need at least two cycles recovery */ - if (recover < 2) - read_cycle = active + 2; - - /* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */ - ncs_read_setup = 1; - ncs_read_pulse = read_cycle - 2; - - /* Write timings same as read timings */ - write_cycle = read_cycle; - nwe_setup = nrd_setup; - nwe_pulse = nrd_pulse; - ncs_write_setup = ncs_read_setup; - ncs_write_pulse = ncs_read_pulse; - - dev_dbg(dev, "ATA timings: nrd_setup = %lu nrd_pulse = %lu nrd_cycle = %lu\n", - nrd_setup, nrd_pulse, read_cycle); - dev_dbg(dev, "ATA timings: nwe_setup = %lu nwe_pulse = %lu nwe_cycle = %lu\n", - nwe_setup, nwe_pulse, write_cycle); - dev_dbg(dev, "ATA timings: ncs_read_setup = %lu ncs_read_pulse = %lu\n", - ncs_read_setup, ncs_read_pulse); - dev_dbg(dev, "ATA timings: ncs_write_setup = %lu ncs_write_pulse = %lu\n", - ncs_write_setup, ncs_write_pulse); + dev_dbg(dev, "Use IORDY=%u, TDF Cycles=%u\n", use_iordy, tdf_cycles); + info->mode |= AT91_SMC_TDF_(tdf_cycles); + /* write SMC Setup Register */ at91_sys_write(AT91_SMC_SETUP(info->cs), - AT91_SMC_NWESETUP_(nwe_setup) | - AT91_SMC_NRDSETUP_(nrd_setup) | - AT91_SMC_NCS_WRSETUP_(ncs_write_setup) | - AT91_SMC_NCS_RDSETUP_(ncs_read_setup)); - + AT91_SMC_NWESETUP_(setup) | + AT91_SMC_NRDSETUP_(setup) | + AT91_SMC_NCS_WRSETUP_(cs_setup) | + AT91_SMC_NCS_RDSETUP_(cs_setup)); + /* write SMC Pulse Register */ at91_sys_write(AT91_SMC_PULSE(info->cs), - AT91_SMC_NWEPULSE_(nwe_pulse) | - AT91_SMC_NRDPULSE_(nrd_pulse) | - AT91_SMC_NCS_WRPULSE_(ncs_write_pulse) | - AT91_SMC_NCS_RDPULSE_(ncs_read_pulse)); - + AT91_SMC_NWEPULSE_(pulse) | + AT91_SMC_NRDPULSE_(pulse) | + AT91_SMC_NCS_WRPULSE_(cs_pulse) | + AT91_SMC_NCS_RDPULSE_(cs_pulse)); + /* write SMC Cycle Register */ at91_sys_write(AT91_SMC_CYCLE(info->cs), - AT91_SMC_NWECYCLE_(write_cycle) | - AT91_SMC_NRDCYCLE_(read_cycle)); - - return; + AT91_SMC_NWECYCLE_(cycle) | + AT91_SMC_NRDCYCLE_(cycle)); + /* write SMC Mode Register*/ + at91_sys_write(AT91_SMC_MODE(info->cs), info->mode); } static void pata_at91_set_piomode(struct ata_port *ap, struct ata_device *adev) @@ -156,15 +277,9 @@ static void pata_at91_set_piomode(struct ata_port *ap, struct ata_device *adev) if (ret) { dev_warn(ap->dev, "Failed to compute ATA timing %d, " "set PIO_0 timing\n", ret); - set_smc_timing(ap->dev, info, &initial_timing); - } else { - set_smc_timing(ap->dev, info, &timing); + timing = *ata_timing_find_mode(XFER_PIO_0); } - - /* Setup SMC mode */ - set_smc_mode(info); - - return; + set_smc_timing(ap->dev, adev, info, &timing); } static unsigned int pata_at91_data_xfer_noirq(struct ata_device *dev, @@ -330,7 +445,7 @@ static int __devexit pata_at91_remove(struct platform_device *pdev) static struct platform_driver pata_at91_driver = { .probe = pata_at91_probe, .remove = __devexit_p(pata_at91_remove), - .driver = { + .driver = { .name = DRV_NAME, .owner = THIS_MODULE, }, |