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authorViresh Kumar <viresh.kumar@linaro.org>2013-04-04 12:54:16 +0000
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2013-04-10 13:19:24 +0200
commit59a2e613d07fbd592ff711c87458eabcf9c98902 (patch)
tree18ebcdccafa518791a17c94133144d17e73f6807 /arch/arm/mach-sa1100/cpu-sa1110.c
parentb7e614c8bf5c898b172d7dfed9853fdda35be5cc (diff)
downloadop-kernel-dev-59a2e613d07fbd592ff711c87458eabcf9c98902.zip
op-kernel-dev-59a2e613d07fbd592ff711c87458eabcf9c98902.tar.gz
cpufreq: sa11x0: move cpufreq driver to drivers/cpufreq
This patch moves cpufreq driver of ARM based sa11x0 platform to drivers/cpufreq. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'arch/arm/mach-sa1100/cpu-sa1110.c')
-rw-r--r--arch/arm/mach-sa1100/cpu-sa1110.c407
1 files changed, 0 insertions, 407 deletions
diff --git a/arch/arm/mach-sa1100/cpu-sa1110.c b/arch/arm/mach-sa1100/cpu-sa1110.c
deleted file mode 100644
index 38a7733..0000000
--- a/arch/arm/mach-sa1100/cpu-sa1110.c
+++ /dev/null
@@ -1,407 +0,0 @@
-/*
- * linux/arch/arm/mach-sa1100/cpu-sa1110.c
- *
- * Copyright (C) 2001 Russell King
- *
- * 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.
- *
- * Note: there are two erratas that apply to the SA1110 here:
- * 7 - SDRAM auto-power-up failure (rev A0)
- * 13 - Corruption of internal register reads/writes following
- * SDRAM reads (rev A0, B0, B1)
- *
- * We ignore rev. A0 and B0 devices; I don't think they're worth supporting.
- *
- * The SDRAM type can be passed on the command line as cpu_sa1110.sdram=type
- */
-#include <linux/cpufreq.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-
-#include <asm/cputype.h>
-#include <asm/mach-types.h>
-
-#include <mach/hardware.h>
-
-#include "generic.h"
-
-#undef DEBUG
-
-struct sdram_params {
- const char name[20];
- u_char rows; /* bits */
- u_char cas_latency; /* cycles */
- u_char tck; /* clock cycle time (ns) */
- u_char trcd; /* activate to r/w (ns) */
- u_char trp; /* precharge to activate (ns) */
- u_char twr; /* write recovery time (ns) */
- u_short refresh; /* refresh time for array (us) */
-};
-
-struct sdram_info {
- u_int mdcnfg;
- u_int mdrefr;
- u_int mdcas[3];
-};
-
-static struct sdram_params sdram_tbl[] __initdata = {
- { /* Toshiba TC59SM716 CL2 */
- .name = "TC59SM716-CL2",
- .rows = 12,
- .tck = 10,
- .trcd = 20,
- .trp = 20,
- .twr = 10,
- .refresh = 64000,
- .cas_latency = 2,
- }, { /* Toshiba TC59SM716 CL3 */
- .name = "TC59SM716-CL3",
- .rows = 12,
- .tck = 8,
- .trcd = 20,
- .trp = 20,
- .twr = 8,
- .refresh = 64000,
- .cas_latency = 3,
- }, { /* Samsung K4S641632D TC75 */
- .name = "K4S641632D",
- .rows = 14,
- .tck = 9,
- .trcd = 27,
- .trp = 20,
- .twr = 9,
- .refresh = 64000,
- .cas_latency = 3,
- }, { /* Samsung K4S281632B-1H */
- .name = "K4S281632B-1H",
- .rows = 12,
- .tck = 10,
- .trp = 20,
- .twr = 10,
- .refresh = 64000,
- .cas_latency = 3,
- }, { /* Samsung KM416S4030CT */
- .name = "KM416S4030CT",
- .rows = 13,
- .tck = 8,
- .trcd = 24, /* 3 CLKs */
- .trp = 24, /* 3 CLKs */
- .twr = 16, /* Trdl: 2 CLKs */
- .refresh = 64000,
- .cas_latency = 3,
- }, { /* Winbond W982516AH75L CL3 */
- .name = "W982516AH75L",
- .rows = 16,
- .tck = 8,
- .trcd = 20,
- .trp = 20,
- .twr = 8,
- .refresh = 64000,
- .cas_latency = 3,
- }, { /* Micron MT48LC8M16A2TG-75 */
- .name = "MT48LC8M16A2TG-75",
- .rows = 12,
- .tck = 8,
- .trcd = 20,
- .trp = 20,
- .twr = 8,
- .refresh = 64000,
- .cas_latency = 3,
- },
-};
-
-static struct sdram_params sdram_params;
-
-/*
- * Given a period in ns and frequency in khz, calculate the number of
- * cycles of frequency in period. Note that we round up to the next
- * cycle, even if we are only slightly over.
- */
-static inline u_int ns_to_cycles(u_int ns, u_int khz)
-{
- return (ns * khz + 999999) / 1000000;
-}
-
-/*
- * Create the MDCAS register bit pattern.
- */
-static inline void set_mdcas(u_int *mdcas, int delayed, u_int rcd)
-{
- u_int shift;
-
- rcd = 2 * rcd - 1;
- shift = delayed + 1 + rcd;
-
- mdcas[0] = (1 << rcd) - 1;
- mdcas[0] |= 0x55555555 << shift;
- mdcas[1] = mdcas[2] = 0x55555555 << (shift & 1);
-}
-
-static void
-sdram_calculate_timing(struct sdram_info *sd, u_int cpu_khz,
- struct sdram_params *sdram)
-{
- u_int mem_khz, sd_khz, trp, twr;
-
- mem_khz = cpu_khz / 2;
- sd_khz = mem_khz;
-
- /*
- * If SDCLK would invalidate the SDRAM timings,
- * run SDCLK at half speed.
- *
- * CPU steppings prior to B2 must either run the memory at
- * half speed or use delayed read latching (errata 13).
- */
- if ((ns_to_cycles(sdram->tck, sd_khz) > 1) ||
- (CPU_REVISION < CPU_SA1110_B2 && sd_khz < 62000))
- sd_khz /= 2;
-
- sd->mdcnfg = MDCNFG & 0x007f007f;
-
- twr = ns_to_cycles(sdram->twr, mem_khz);
-
- /* trp should always be >1 */
- trp = ns_to_cycles(sdram->trp, mem_khz) - 1;
- if (trp < 1)
- trp = 1;
-
- sd->mdcnfg |= trp << 8;
- sd->mdcnfg |= trp << 24;
- sd->mdcnfg |= sdram->cas_latency << 12;
- sd->mdcnfg |= sdram->cas_latency << 28;
- sd->mdcnfg |= twr << 14;
- sd->mdcnfg |= twr << 30;
-
- sd->mdrefr = MDREFR & 0xffbffff0;
- sd->mdrefr |= 7;
-
- if (sd_khz != mem_khz)
- sd->mdrefr |= MDREFR_K1DB2;
-
- /* initial number of '1's in MDCAS + 1 */
- set_mdcas(sd->mdcas, sd_khz >= 62000,
- ns_to_cycles(sdram->trcd, mem_khz));
-
-#ifdef DEBUG
- printk(KERN_DEBUG "MDCNFG: %08x MDREFR: %08x MDCAS0: %08x MDCAS1: %08x MDCAS2: %08x\n",
- sd->mdcnfg, sd->mdrefr, sd->mdcas[0], sd->mdcas[1],
- sd->mdcas[2]);
-#endif
-}
-
-/*
- * Set the SDRAM refresh rate.
- */
-static inline void sdram_set_refresh(u_int dri)
-{
- MDREFR = (MDREFR & 0xffff000f) | (dri << 4);
- (void) MDREFR;
-}
-
-/*
- * Update the refresh period. We do this such that we always refresh
- * the SDRAMs within their permissible period. The refresh period is
- * always a multiple of the memory clock (fixed at cpu_clock / 2).
- *
- * FIXME: we don't currently take account of burst accesses here,
- * but neither do Intels DM nor Angel.
- */
-static void
-sdram_update_refresh(u_int cpu_khz, struct sdram_params *sdram)
-{
- u_int ns_row = (sdram->refresh * 1000) >> sdram->rows;
- u_int dri = ns_to_cycles(ns_row, cpu_khz / 2) / 32;
-
-#ifdef DEBUG
- mdelay(250);
- printk(KERN_DEBUG "new dri value = %d\n", dri);
-#endif
-
- sdram_set_refresh(dri);
-}
-
-/*
- * Ok, set the CPU frequency.
- */
-static int sa1110_target(struct cpufreq_policy *policy,
- unsigned int target_freq,
- unsigned int relation)
-{
- struct sdram_params *sdram = &sdram_params;
- struct cpufreq_freqs freqs;
- struct sdram_info sd;
- unsigned long flags;
- unsigned int ppcr, unused;
-
- switch (relation) {
- case CPUFREQ_RELATION_L:
- ppcr = sa11x0_freq_to_ppcr(target_freq);
- if (sa11x0_ppcr_to_freq(ppcr) > policy->max)
- ppcr--;
- break;
- case CPUFREQ_RELATION_H:
- ppcr = sa11x0_freq_to_ppcr(target_freq);
- if (ppcr && (sa11x0_ppcr_to_freq(ppcr) > target_freq) &&
- (sa11x0_ppcr_to_freq(ppcr-1) >= policy->min))
- ppcr--;
- break;
- default:
- return -EINVAL;
- }
-
- freqs.old = sa11x0_getspeed(0);
- freqs.new = sa11x0_ppcr_to_freq(ppcr);
-
- sdram_calculate_timing(&sd, freqs.new, sdram);
-
-#if 0
- /*
- * These values are wrong according to the SA1110 documentation
- * and errata, but they seem to work. Need to get a storage
- * scope on to the SDRAM signals to work out why.
- */
- if (policy->max < 147500) {
- sd.mdrefr |= MDREFR_K1DB2;
- sd.mdcas[0] = 0xaaaaaa7f;
- } else {
- sd.mdrefr &= ~MDREFR_K1DB2;
- sd.mdcas[0] = 0xaaaaaa9f;
- }
- sd.mdcas[1] = 0xaaaaaaaa;
- sd.mdcas[2] = 0xaaaaaaaa;
-#endif
-
- cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
-
- /*
- * The clock could be going away for some time. Set the SDRAMs
- * to refresh rapidly (every 64 memory clock cycles). To get
- * through the whole array, we need to wait 262144 mclk cycles.
- * We wait 20ms to be safe.
- */
- sdram_set_refresh(2);
- if (!irqs_disabled())
- msleep(20);
- else
- mdelay(20);
-
- /*
- * Reprogram the DRAM timings with interrupts disabled, and
- * ensure that we are doing this within a complete cache line.
- * This means that we won't access SDRAM for the duration of
- * the programming.
- */
- local_irq_save(flags);
- asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
- udelay(10);
- __asm__ __volatile__("\n\
- b 2f \n\
- .align 5 \n\
-1: str %3, [%1, #0] @ MDCNFG \n\
- str %4, [%1, #28] @ MDREFR \n\
- str %5, [%1, #4] @ MDCAS0 \n\
- str %6, [%1, #8] @ MDCAS1 \n\
- str %7, [%1, #12] @ MDCAS2 \n\
- str %8, [%2, #0] @ PPCR \n\
- ldr %0, [%1, #0] \n\
- b 3f \n\
-2: b 1b \n\
-3: nop \n\
- nop"
- : "=&r" (unused)
- : "r" (&MDCNFG), "r" (&PPCR), "0" (sd.mdcnfg),
- "r" (sd.mdrefr), "r" (sd.mdcas[0]),
- "r" (sd.mdcas[1]), "r" (sd.mdcas[2]), "r" (ppcr));
- local_irq_restore(flags);
-
- /*
- * Now, return the SDRAM refresh back to normal.
- */
- sdram_update_refresh(freqs.new, sdram);
-
- cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-
- return 0;
-}
-
-static int __init sa1110_cpu_init(struct cpufreq_policy *policy)
-{
- if (policy->cpu != 0)
- return -EINVAL;
- policy->cur = policy->min = policy->max = sa11x0_getspeed(0);
- policy->cpuinfo.min_freq = 59000;
- policy->cpuinfo.max_freq = 287000;
- policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
- return 0;
-}
-
-/* sa1110_driver needs __refdata because it must remain after init registers
- * it with cpufreq_register_driver() */
-static struct cpufreq_driver sa1110_driver __refdata = {
- .flags = CPUFREQ_STICKY,
- .verify = sa11x0_verify_speed,
- .target = sa1110_target,
- .get = sa11x0_getspeed,
- .init = sa1110_cpu_init,
- .name = "sa1110",
-};
-
-static struct sdram_params *sa1110_find_sdram(const char *name)
-{
- struct sdram_params *sdram;
-
- for (sdram = sdram_tbl; sdram < sdram_tbl + ARRAY_SIZE(sdram_tbl);
- sdram++)
- if (strcmp(name, sdram->name) == 0)
- return sdram;
-
- return NULL;
-}
-
-static char sdram_name[16];
-
-static int __init sa1110_clk_init(void)
-{
- struct sdram_params *sdram;
- const char *name = sdram_name;
-
- if (!cpu_is_sa1110())
- return -ENODEV;
-
- if (!name[0]) {
- if (machine_is_assabet())
- name = "TC59SM716-CL3";
- if (machine_is_pt_system3())
- name = "K4S641632D";
- if (machine_is_h3100())
- name = "KM416S4030CT";
- if (machine_is_jornada720())
- name = "K4S281632B-1H";
- if (machine_is_nanoengine())
- name = "MT48LC8M16A2TG-75";
- }
-
- sdram = sa1110_find_sdram(name);
- if (sdram) {
- printk(KERN_DEBUG "SDRAM: tck: %d trcd: %d trp: %d"
- " twr: %d refresh: %d cas_latency: %d\n",
- sdram->tck, sdram->trcd, sdram->trp,
- sdram->twr, sdram->refresh, sdram->cas_latency);
-
- memcpy(&sdram_params, sdram, sizeof(sdram_params));
-
- return cpufreq_register_driver(&sa1110_driver);
- }
-
- return 0;
-}
-
-module_param_string(sdram, sdram_name, sizeof(sdram_name), 0);
-arch_initcall(sa1110_clk_init);
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