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/*
* SMS/SDRC (SDRAM controller) common code for OMAP2/3
*
* Copyright (C) 2005, 2008 Texas Instruments Inc.
* Copyright (C) 2005, 2008 Nokia Corporation
*
* Tony Lindgren <tony@atomide.com>
* Paul Walmsley
* Richard Woodruff <r-woodruff2@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.
*/
#undef DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <mach/common.h>
#include <mach/clock.h>
#include <mach/sram.h>
#include "prm.h"
#include <mach/sdrc.h>
#include "sdrc.h"
static struct omap_sdrc_params *sdrc_init_params_cs0, *sdrc_init_params_cs1;
void __iomem *omap2_sdrc_base;
void __iomem *omap2_sms_base;
/* SDRC_POWER register bits */
#define SDRC_POWER_EXTCLKDIS_SHIFT 3
#define SDRC_POWER_PWDENA_SHIFT 2
#define SDRC_POWER_PAGEPOLICY_SHIFT 0
/**
* omap2_sdrc_get_params - return SDRC register values for a given clock rate
* @r: SDRC clock rate (in Hz)
* @sdrc_cs0: chip select 0 ram timings **
* @sdrc_cs1: chip select 1 ram timings **
*
* Return pre-calculated values for the SDRC_ACTIM_CTRLA,
* SDRC_ACTIM_CTRLB, SDRC_RFR_CTRL and SDRC_MR registers in sdrc_cs[01]
* structs,for a given SDRC clock rate 'r'.
* These parameters control various timing delays in the SDRAM controller
* that are expressed in terms of the number of SDRC clock cycles to
* wait; hence the clock rate dependency.
*
* Supports 2 different timing parameters for both chip selects.
*
* Note 1: the sdrc_init_params_cs[01] must be sorted rate descending.
* Note 2: If sdrc_init_params_cs_1 is not NULL it must be of same size
* as sdrc_init_params_cs_0.
*
* Fills in the struct omap_sdrc_params * for each chip select.
* Returns 0 upon success or -1 upon failure.
*/
int omap2_sdrc_get_params(unsigned long r,
struct omap_sdrc_params **sdrc_cs0,
struct omap_sdrc_params **sdrc_cs1)
{
struct omap_sdrc_params *sp0, *sp1;
if (!sdrc_init_params_cs0)
return -1;
sp0 = sdrc_init_params_cs0;
sp1 = sdrc_init_params_cs1;
while (sp0->rate && sp0->rate != r) {
sp0++;
if (sdrc_init_params_cs1)
sp1++;
}
if (!sp0->rate)
return -1;
*sdrc_cs0 = sp0;
*sdrc_cs1 = sp1;
return 0;
}
void __init omap2_set_globals_sdrc(struct omap_globals *omap2_globals)
{
omap2_sdrc_base = omap2_globals->sdrc;
omap2_sms_base = omap2_globals->sms;
}
/**
* omap2_sdrc_init - initialize SMS, SDRC devices on boot
* @sdrc_cs[01]: pointers to a null-terminated list of struct omap_sdrc_params
* Support for 2 chip selects timings
*
* Turn on smart idle modes for SDRAM scheduler and controller.
* Program a known-good configuration for the SDRC to deal with buggy
* bootloaders.
*/
void __init omap2_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
struct omap_sdrc_params *sdrc_cs1)
{
u32 l;
l = sms_read_reg(SMS_SYSCONFIG);
l &= ~(0x3 << 3);
l |= (0x2 << 3);
sms_write_reg(l, SMS_SYSCONFIG);
l = sdrc_read_reg(SDRC_SYSCONFIG);
l &= ~(0x3 << 3);
l |= (0x2 << 3);
sdrc_write_reg(l, SDRC_SYSCONFIG);
sdrc_init_params_cs0 = sdrc_cs0;
sdrc_init_params_cs1 = sdrc_cs1;
/* XXX Enable SRFRONIDLEREQ here also? */
/*
* PWDENA should not be set due to 34xx erratum 1.150 - PWDENA
* can cause random memory corruption
*/
l = (1 << SDRC_POWER_EXTCLKDIS_SHIFT) |
(1 << SDRC_POWER_PAGEPOLICY_SHIFT);
sdrc_write_reg(l, SDRC_POWER);
}
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