arch/arm/mach-omap2/memory.c

   1 /*
   2  * linux/arch/arm/mach-omap2/memory.c
   3  *
   4  * Memory timing related functions for OMAP24XX
   5  *
   6  * Copyright (C) 2005 Texas Instruments Inc.
   7  * Richard Woodruff <r-woodruff2@ti.com>
   8  *
   9  * Copyright (C) 2005 Nokia Corporation
  10  * Tony Lindgren <tony@atomide.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/kernel.h>
  19 #include <linux/device.h>
  20 #include <linux/list.h>
  21 #include <linux/errno.h>
  22 #include <linux/delay.h>
  23 #include <linux/clk.h>
  24 #include <linux/io.h>
  25
  26 #include <mach/common.h>
  27 #include <mach/clock.h>
  28 #include <mach/sram.h>
  29
  30 #include "prm.h"
  31
  32 #include "memory.h"
  33 #include "sdrc.h"
  34
  35 void __iomem *omap2_sdrc_base;
  36 void __iomem *omap2_sms_base;
  37
  38 static struct memory_timings mem_timings;
  39 static u32 curr_perf_level = CORE_CLK_SRC_DPLL_X2;
  40
  41 u32 omap2_memory_get_slow_dll_ctrl(void)
  42 {
  43         return mem_timings.slow_dll_ctrl;
  44 }
  45
  46 u32 omap2_memory_get_fast_dll_ctrl(void)
  47 {
  48         return mem_timings.fast_dll_ctrl;
  49 }
  50
  51 u32 omap2_memory_get_type(void)
  52 {
  53         return mem_timings.m_type;
  54 }
  55
  56 /*
  57  * Check the DLL lock state, and return tue if running in unlock mode.
  58  * This is needed to compensate for the shifted DLL value in unlock mode.
  59  */
  60 u32 omap2_dll_force_needed(void)
  61 {
  62         /* dlla and dllb are a set */
  63         u32 dll_state = sdrc_read_reg(SDRC_DLLA_CTRL);
  64
  65         if ((dll_state & (1 << 2)) == (1 << 2))
  66                 return 1;
  67         else
  68                 return 0;
  69 }
  70
  71 /*
  72  * 'level' is the value to store to CM_CLKSEL2_PLL.CORE_CLK_SRC.
  73  * Practical values are CORE_CLK_SRC_DPLL (for CORE_CLK = DPLL_CLK) or
  74  * CORE_CLK_SRC_DPLL_X2 (for CORE_CLK = * DPLL_CLK * 2)
  75  */
  76 u32 omap2_reprogram_sdrc(u32 level, u32 force)
  77 {
  78         u32 dll_ctrl, m_type;
  79         u32 prev = curr_perf_level;
  80         unsigned long flags;
  81
  82         if ((curr_perf_level == level) && !force)
  83                 return prev;
  84
  85         if (level == CORE_CLK_SRC_DPLL) {
  86                 dll_ctrl = omap2_memory_get_slow_dll_ctrl();
  87         } else if (level == CORE_CLK_SRC_DPLL_X2) {
  88                 dll_ctrl = omap2_memory_get_fast_dll_ctrl();
  89         } else {
  90                 return prev;
  91         }
  92
  93         m_type = omap2_memory_get_type();
  94
  95         local_irq_save(flags);
  96         __raw_writel(0xffff, OMAP24XX_PRCM_VOLTSETUP);
  97         omap2_sram_reprogram_sdrc(level, dll_ctrl, m_type);
  98         curr_perf_level = level;
  99         local_irq_restore(flags);
 100
 101         return prev;
 102 }
 103
 104 void omap2_init_memory_params(u32 force_lock_to_unlock_mode)
 105 {
 106         unsigned long dll_cnt;
 107         u32 fast_dll = 0;
 108
 109         mem_timings.m_type = !((sdrc_read_reg(SDRC_MR_0) & 0x3) == 0x1); /* DDR = 1, SDR = 0 */
 110
 111         /* 2422 es2.05 and beyond has a single SIP DDR instead of 2 like others.
 112          * In the case of 2422, its ok to use CS1 instead of CS0.
 113          */
 114         if (cpu_is_omap2422())
 115                 mem_timings.base_cs = 1;
 116         else
 117                 mem_timings.base_cs = 0;
 118
 119         if (mem_timings.m_type != M_DDR)
 120                 return;
 121
 122         /* With DDR we need to determine the low frequency DLL value */
 123         if (((mem_timings.fast_dll_ctrl & (1 << 2)) == M_LOCK_CTRL))
 124                 mem_timings.dll_mode = M_UNLOCK;
 125         else
 126                 mem_timings.dll_mode = M_LOCK;
 127
 128         if (mem_timings.base_cs == 0) {
 129                 fast_dll = sdrc_read_reg(SDRC_DLLA_CTRL);
 130                 dll_cnt = sdrc_read_reg(SDRC_DLLA_STATUS) & 0xff00;
 131         } else {
 132                 fast_dll = sdrc_read_reg(SDRC_DLLB_CTRL);
 133                 dll_cnt = sdrc_read_reg(SDRC_DLLB_STATUS) & 0xff00;
 134         }
 135         if (force_lock_to_unlock_mode) {
 136                 fast_dll &= ~0xff00;
 137                 fast_dll |= dll_cnt;            /* Current lock mode */
 138         }
 139         /* set fast timings with DLL filter disabled */
 140         mem_timings.fast_dll_ctrl = (fast_dll | (3 << 8));
 141
 142         /* No disruptions, DDR will be offline & C-ABI not followed */
 143         omap2_sram_ddr_init(&mem_timings.slow_dll_ctrl,
 144                             mem_timings.fast_dll_ctrl,
 145                             mem_timings.base_cs,
 146                             force_lock_to_unlock_mode);
 147         mem_timings.slow_dll_ctrl &= 0xff00;    /* Keep lock value */
 148
 149         /* Turn status into unlock ctrl */
 150         mem_timings.slow_dll_ctrl |=
 151                 ((mem_timings.fast_dll_ctrl & 0xF) | (1 << 2));
 152
 153         /* 90 degree phase for anything below 133Mhz + disable DLL filter */
 154         mem_timings.slow_dll_ctrl |= ((1 << 1) | (3 << 8));
 155 }
 156
 157 void __init omap2_set_globals_memory(struct omap_globals *omap2_globals)
 158 {
 159         omap2_sdrc_base = omap2_globals->sdrc;
 160         omap2_sms_base = omap2_globals->sms;
 161 }
 162
 163 /* turn on smart idle modes for SDRAM scheduler and controller */
 164 void __init omap2_init_memory(void)
 165 {
 166         u32 l;
 167
 168         l = sms_read_reg(SMS_SYSCONFIG);
 169         l &= ~(0x3 << 3);
 170         l |= (0x2 << 3);
 171         sms_write_reg(l, SMS_SYSCONFIG);
 172
 173         l = sdrc_read_reg(SDRC_SYSCONFIG);
 174         l &= ~(0x3 << 3);
 175         l |= (0x2 << 3);
 176         sdrc_write_reg(l, SDRC_SYSCONFIG);
 177 }