diff options
Diffstat (limited to 'arch/arm/mach-omap2/sdrc.c')
-rw-r--r-- | arch/arm/mach-omap2/sdrc.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sdrc.c b/arch/arm/mach-omap2/sdrc.c new file mode 100644 index 0000000000..b1bf9e24d4 --- /dev/null +++ b/arch/arm/mach-omap2/sdrc.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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> + */ +#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 "common.h" +#include "clock.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; + +struct omap2_sms_regs { + u32 sms_sysconfig; +}; + +static struct omap2_sms_regs sms_context; + +/* SDRC_POWER register bits */ +#define SDRC_POWER_EXTCLKDIS_SHIFT 3 +#define SDRC_POWER_PWDENA_SHIFT 2 +#define SDRC_POWER_PAGEPOLICY_SHIFT 0 + +/** + * omap2_sms_save_context - Save SMS registers + * + * Save SMS registers that need to be restored after off mode. + */ +static void omap2_sms_save_context(void) +{ + sms_context.sms_sysconfig = sms_read_reg(SMS_SYSCONFIG); +} + +/** + * omap2_sms_restore_context - Restore SMS registers + * + * Restore SMS registers that need to be Restored after off mode. + */ +void omap2_sms_restore_context(void) +{ + sms_write_reg(sms_context.sms_sysconfig, SMS_SYSCONFIG); +} + +void __init omap2_set_globals_sdrc(void __iomem *sdrc, void __iomem *sms) +{ + omap2_sdrc_base = sdrc; + omap2_sms_base = 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); + omap2_sms_save_context(); +} |