From d49679e5928709bce8937dce396458b139c4b34d Mon Sep 17 00:00:00 2001 From: Kuninori Morimoto Date: Tue, 12 Jun 2012 02:36:21 -0700 Subject: [PATCH] ARM: shmobile: r8a7740: add MERAM work-around r8a7740 chip has lasting errata on MERAM buffer, and this patch adds its work-around on setup-r8a7740.c It solved CEU/VIO6C/2D-DMAC/VCP1/VPU5F/JPU/DISP memroy access error. But MERAM driver can't control this issue, since this work-around requires access to non-MERAM register address. So, This it will be called as board specific code at this point. Signed-off-by: Kuninori Morimoto Tested-by: Simon Horman Acked-by: Magnus Damm Signed-off-by: Rafael J. Wysocki --- arch/arm/mach-shmobile/board-armadillo800eva.c | 1 + arch/arm/mach-shmobile/include/mach/common.h | 1 + arch/arm/mach-shmobile/setup-r8a7740.c | 18 ++++++++++++++++++ 3 files changed, 20 insertions(+) diff --git a/arch/arm/mach-shmobile/board-armadillo800eva.c b/arch/arm/mach-shmobile/board-armadillo800eva.c index 9e37026ef9dd..6e6839d0a2dc 100644 --- a/arch/arm/mach-shmobile/board-armadillo800eva.c +++ b/arch/arm/mach-shmobile/board-armadillo800eva.c @@ -587,6 +587,7 @@ static void __init eva_init(void) eva_clock_init(); r8a7740_pinmux_init(); + r8a7740_meram_workaround(); /* SCIFA1 */ gpio_request(GPIO_FN_SCIFA1_RXD, NULL); diff --git a/arch/arm/mach-shmobile/include/mach/common.h b/arch/arm/mach-shmobile/include/mach/common.h index 01e2bc014f15..45e61dada030 100644 --- a/arch/arm/mach-shmobile/include/mach/common.h +++ b/arch/arm/mach-shmobile/include/mach/common.h @@ -77,6 +77,7 @@ extern void r8a7779_add_standard_devices(void); extern void r8a7779_clock_init(void); extern void r8a7779_pinmux_init(void); extern void r8a7779_pm_init(void); +extern void r8a7740_meram_workaround(void); extern unsigned int r8a7779_get_core_count(void); extern int r8a7779_platform_cpu_kill(unsigned int cpu); diff --git a/arch/arm/mach-shmobile/setup-r8a7740.c b/arch/arm/mach-shmobile/setup-r8a7740.c index ec4eb49c1693..366311b3dc73 100644 --- a/arch/arm/mach-shmobile/setup-r8a7740.c +++ b/arch/arm/mach-shmobile/setup-r8a7740.c @@ -324,6 +324,24 @@ static struct platform_device *r8a7740_late_devices[] __initdata = { &i2c1_device, }; +/* + * r8a7740 chip has lasting errata on MERAM buffer. + * this is work-around for it. + * see + * "Media RAM (MERAM)" on r8a7740 documentation + */ +#define MEBUFCNTR 0xFE950098 +void r8a7740_meram_workaround(void) +{ + void __iomem *reg; + + reg = ioremap_nocache(MEBUFCNTR, 4); + if (reg) { + iowrite32(0x01600164, reg); + iounmap(reg); + } +} + #define ICCR 0x0004 #define ICSTART 0x0070 -- 2.20.1