diff options
Diffstat (limited to 'arch/arm/mach-sa1100/cpu-sa1110.c')
-rw-r--r-- | arch/arm/mach-sa1100/cpu-sa1110.c | 408 |
1 files changed, 0 insertions, 408 deletions
diff --git a/arch/arm/mach-sa1100/cpu-sa1110.c b/arch/arm/mach-sa1100/cpu-sa1110.c deleted file mode 100644 index 48c45b0c92b..00000000000 --- a/arch/arm/mach-sa1100/cpu-sa1110.c +++ /dev/null @@ -1,408 +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); - freqs.cpu = 0; - - 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(&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(&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); |