[U-Boot] [PATCH] kirkwood: implement kw_sdram_bs_set()

Gerlando Falauto
2012-06-29T11:37:54Z

Some boards might be equipped with different SDRAM configurations.
When that is the case, CPU CS Window Size Register (CS[0]n Size) should
be set to the biggest value through board.cfg file; then its value
can be fixed at runtime according to the detected SDRAM size.

Therefore, implement kw_sdram_bs_set(), to be called for instance within
board_early_init_f().

Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Valentin Longchamp <valentin.longchamp@keymile.com>
Cc: Holger Brunck <holger.brunck@keymile.com>
---
arch/arm/cpu/arm926ejs/kirkwood/dram.c | 28 ++++++++++++++++++++++++++--
arch/arm/include/asm/arch-kirkwood/cpu.h | 2 ++
2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/kirkwood/dram.c b/arch/arm/cpu/arm926ejs/kirkwood/dram.c
index 2441554..e5409f1 100644
--- a/arch/arm/cpu/arm926ejs/kirkwood/dram.c
+++ b/arch/arm/cpu/arm926ejs/kirkwood/dram.c
@@ -28,8 +28,15 @@

DECLARE_GLOBAL_DATA_PTR;

-#define KW_REG_CPUCS_WIN_BAR(x) (KW_REGISTER(0x1500) + (x * 0x08))
-#define KW_REG_CPUCS_WIN_SZ(x) (KW_REGISTER(0x1504) + (x * 0x08))
+/* Kirkwood memory registers */
+#define KW_REG_CPUCS_WIN_BAR(x) (KW_REGISTER(0x1500) + ((x) * 0x08))
+#define KW_REG_CPUCS_WIN_SZ(x) (KW_REGISTER(0x1504) + ((x) * 0x08))
+
+#define KW_REG_CPUCS_WIN_ENABLE (1 << 0)
+#define KW_REG_CPUCS_WIN_WR_PROTECT (1 << 1)
+#define KW_REG_CPUCS_WIN_WIN0_CS(x) (((x) & 0x3) << 2)
+#define KW_REG_CPUCS_WIN_SIZE(x) (((x) & 0xff) << 24)
+
/*
* kw_sdram_bar - reads SDRAM Base Address Register
*/
@@ -60,6 +67,23 @@ u32 kw_sdram_bs(enum memory_bank bank)
return result;
}

+/*
+ * kw_sdram_bs_set - writes SDRAM Bank size
+ */
+void kw_sdram_bs_set(enum memory_bank bank, u32 size)
+{
+ /* Read current register value */
+ u32 reg = readl(KW_REG_CPUCS_WIN_SZ(bank));
+
+ /* Clear window size */
+ reg &= ~KW_REG_CPUCS_WIN_SIZE(0xFF);
+
+ /* Set new window size */
+ reg |= KW_REG_CPUCS_WIN_SIZE((size - 1) >> 24);
+
+ writel(reg, KW_REG_CPUCS_WIN_SZ(bank));
+}
+
#ifndef CONFIG_SYS_BOARD_DRAM_INIT
int dram_init(void)
{
diff --git a/arch/arm/include/asm/arch-kirkwood/cpu.h b/arch/arm/include/asm/arch-kirkwood/cpu.h
index d28c51a..807154e 100644
--- a/arch/arm/include/asm/arch-kirkwood/cpu.h
+++ b/arch/arm/include/asm/arch-kirkwood/cpu.h
@@ -159,6 +159,8 @@ void reset_cpu(unsigned long ignored);
unsigned char get_random_hex(void);
unsigned int kw_sdram_bar(enum memory_bank bank);
unsigned int kw_sdram_bs(enum memory_bank bank);
+void kw_sdram_bs_set(enum memory_bank bank, u32 size);
+
int kw_config_adr_windows(void);
void kw_config_gpio(unsigned int gpp0_oe_val, unsigned int gpp1_oe_val,
unsigned int gpp0_oe, unsigned int gpp1_oe);
--
1.7.1