[PATCH] ARM i.MX27: initialize MAX
Sascha Hauer
s.hauer at pengutronix.de
Thu Dec 8 04:17:44 EST 2011
Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
arch/arm/mach-imx/imx27.c | 43 +++++++++++++++++++++++++++
arch/arm/mach-imx/include/mach/imx27-regs.h | 1 +
2 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-imx/imx27.c b/arch/arm/mach-imx/imx27.c
index 86039c4..1af291d 100644
--- a/arch/arm/mach-imx/imx27.c
+++ b/arch/arm/mach-imx/imx27.c
@@ -19,6 +19,7 @@
#include <mach/imx-regs.h>
#include <sizes.h>
#include <init.h>
+#include <io.h>
#include "gpio.h"
@@ -38,11 +39,53 @@ void *imx_gpio_base[] = {
int imx_gpio_count = ARRAY_SIZE(imx_gpio_base) * 32;
+/*
+ * Initialize MAX on i.MX27. necessary to give the DMA engine
+ * higher priority to the memory than the CPU. Needed for proper
+ * audio support
+ */
+#define MAX_SLAVE_MPR_OFFSET 0x0 /* Master Priority register */
+#define MAX_SLAVE_AMPR_OFFSET 0x4 /* Alternate Master Priority register */
+#define MAX_SLAVE_PORT0_OFFSET 0x0
+#define MAX_SLAVE_PORT1_OFFSET 0x100
+#define MAX_SLAVE_PORT2_OFFSET 0x200
+#define MAX_MASTER_PRIO(master, prio) (((prio) << (master) * 4))
+
+#define MASTER_IAHB 0
+#define MASTER_DAHB 1
+#define MASTER_EMMA 2
+#define MASTER_DMA 3
+#define MASTER_SLDC 4
+#define MASTER_CODEC 5
+
+static void imx27_init_max(void)
+{
+ void __iomem *max_base = (void *)IMX_MAX_BASE;
+ u32 val;
+
+ /* 0 is the highest priority */
+ val = MAX_MASTER_PRIO(MASTER_IAHB, 5) |
+ MAX_MASTER_PRIO(MASTER_DAHB, 4) |
+ MAX_MASTER_PRIO(MASTER_EMMA, 1) |
+ MAX_MASTER_PRIO(MASTER_DMA, 2) |
+ MAX_MASTER_PRIO(MASTER_SLDC, 0) |
+ MAX_MASTER_PRIO(MASTER_CODEC, 3);
+
+ writel(val, max_base + MAX_SLAVE_PORT0_OFFSET + MAX_SLAVE_MPR_OFFSET);
+ writel(val, max_base + MAX_SLAVE_PORT1_OFFSET + MAX_SLAVE_MPR_OFFSET);
+ writel(val, max_base + MAX_SLAVE_PORT2_OFFSET + MAX_SLAVE_MPR_OFFSET);
+ writel(val, max_base + MAX_SLAVE_PORT0_OFFSET + MAX_SLAVE_AMPR_OFFSET);
+ writel(val, max_base + MAX_SLAVE_PORT1_OFFSET + MAX_SLAVE_AMPR_OFFSET);
+ writel(val, max_base + MAX_SLAVE_PORT2_OFFSET + MAX_SLAVE_AMPR_OFFSET);
+}
+
static int imx27_init(void)
{
add_generic_device("imx_iim", 0, NULL, IMX_IIM_BASE, SZ_4K,
IORESOURCE_MEM, NULL);
+ imx27_init_max();
+
return 0;
}
coredevice_initcall(imx27_init);
diff --git a/arch/arm/mach-imx/include/mach/imx27-regs.h b/arch/arm/mach-imx/include/mach/imx27-regs.h
index 6754c5a..3a4325e 100644
--- a/arch/arm/mach-imx/include/mach/imx27-regs.h
+++ b/arch/arm/mach-imx/include/mach/imx27-regs.h
@@ -33,6 +33,7 @@
#define IMX_IIM_BASE (0x28000 + IMX_IO_BASE)
#define IMX_OTG_BASE (0x24000 + IMX_IO_BASE)
#define IMX_FEC_BASE (0x2b000 + IMX_IO_BASE)
+#define IMX_MAX_BASE (0x3f000 + IMX_IO_BASE)
#define IMX_NFC_BASE (0xd8000000)
#define IMX_ESD_BASE (0xd8001000)
--
1.7.7.3
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