[PATCHv2 15/19] ARM: OMAP4430: PM: workaround for DDR corruption on second CS
From: Tero Kristo <hidden>
Date: 2012-05-14 10:18:46
Also in:
linux-omap
Subsystem:
arm port, omap power management support, omap2+ support, the rest · Maintainers:
Russell King, Kevin Hilman, Aaro Koskinen, Andreas Kemnade, Roger Quadros, Tony Lindgren, Linus Torvalds
From: Santosh Shilimkar <redacted> Work around for Errata ID: i632 "LPDDR2 Corruption After OFF Mode Transition When CS1 Is Used On EMIF" which impacts OMAP443x silicon The issue occurs when EMIF_SDRAM_CONFIG is restored first before EMIF_SDRAM_CONFIG_2 is not yet restored, the register configuration is not set properly, we apply the required workaround allowing the restore sequence to work properly. Signed-off-by: Santosh Shilimkar <redacted> [t-kristo at ti.com: moved workaround from omap-sar.c to pm44xx.c] Signed-off-by: Tero Kristo <redacted> --- .../include/mach/ctrl_module_wkup_44xx.h | 2 + arch/arm/mach-omap2/pm44xx.c | 37 ++++++++++++++++++++ 2 files changed, 39 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-omap2/include/mach/ctrl_module_wkup_44xx.h b/arch/arm/mach-omap2/include/mach/ctrl_module_wkup_44xx.h
index a0af9ba..b763a79 100644
--- a/arch/arm/mach-omap2/include/mach/ctrl_module_wkup_44xx.h
+++ b/arch/arm/mach-omap2/include/mach/ctrl_module_wkup_44xx.h@@ -28,6 +28,8 @@ #define OMAP4_CTRL_MODULE_WKUP_IP_REVISION 0x0000 #define OMAP4_CTRL_MODULE_WKUP_IP_HWINFO 0x0004 #define OMAP4_CTRL_MODULE_WKUP_IP_SYSCONFIG 0x0010 +#define OMAP4_CTRL_SECURE_EMIF1_SDRAM_CONFIG2_REG 0x0114 +#define OMAP4_CTRL_SECURE_EMIF2_SDRAM_CONFIG2_REG 0x011c #define OMAP4_CTRL_MODULE_WKUP_CONF_DEBUG_SEL_TST_0 0x0460 #define OMAP4_CTRL_MODULE_WKUP_CONF_DEBUG_SEL_TST_1 0x0464 #define OMAP4_CTRL_MODULE_WKUP_CONF_DEBUG_SEL_TST_2 0x0468
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index 215b80e..dfaa254 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c@@ -17,12 +17,18 @@ #include <linux/err.h> #include <linux/slab.h> #include <asm/system_misc.h> +#include <linux/io.h> + +#include <mach/ctrl_module_wkup_44xx.h> +#include <mach/hardware.h> #include "common.h" #include "clockdomain.h" #include "powerdomain.h" #include "pm.h" +#define EMIF_SDRAM_CONFIG2_OFFSET 0xc + struct power_state { struct powerdomain *pwrdm; u32 next_state;
@@ -215,6 +221,37 @@ static int __init omap4_pm_init(void) pr_err("Power Management for TI OMAP4.\n"); + /* + * Work around for OMAP443x Errata i632: "LPDDR2 Corruption After OFF + * Mode Transition When CS1 Is Used On EMIF": + * Overwrite EMIF1/EMIF2 + * SECURE_EMIF1_SDRAM_CONFIG2_REG + * SECURE_EMIF2_SDRAM_CONFIG2_REG + */ + if (cpu_is_omap443x()) { + void __iomem *secure_ctrl_mod; + void __iomem *emif1; + void __iomem *emif2; + u32 val; + + secure_ctrl_mod = ioremap(OMAP4_CTRL_MODULE_WKUP, SZ_4K); + emif1 = ioremap(OMAP44XX_EMIF1_BASE, SZ_1M); + emif2 = ioremap(OMAP44XX_EMIF2_BASE, SZ_1M); + + BUG_ON(!secure_ctrl_mod || !emif1 || !emif2); + + val = __raw_readl(emif1 + EMIF_SDRAM_CONFIG2_OFFSET); + __raw_writel(val, secure_ctrl_mod + + OMAP4_CTRL_SECURE_EMIF1_SDRAM_CONFIG2_REG); + val = __raw_readl(emif2 + EMIF_SDRAM_CONFIG2_OFFSET); + __raw_writel(val, secure_ctrl_mod + + OMAP4_CTRL_SECURE_EMIF2_SDRAM_CONFIG2_REG); + wmb(); + iounmap(secure_ctrl_mod); + iounmap(emif1); + iounmap(emif2); + } + ret = pwrdm_for_each(pwrdms_setup, NULL); if (ret) { pr_err("Failed to setup powerdomains\n");
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1.7.4.1