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Diffstat (limited to 'target/linux/xburst/patches-3.10/013-MIPS-JZ4740-Acquire-and-enable-DMA-controller-clock.patch')
-rw-r--r--target/linux/xburst/patches-3.10/013-MIPS-JZ4740-Acquire-and-enable-DMA-controller-clock.patch80
1 files changed, 80 insertions, 0 deletions
diff --git a/target/linux/xburst/patches-3.10/013-MIPS-JZ4740-Acquire-and-enable-DMA-controller-clock.patch b/target/linux/xburst/patches-3.10/013-MIPS-JZ4740-Acquire-and-enable-DMA-controller-clock.patch
new file mode 100644
index 0000000000..110f061568
--- /dev/null
+++ b/target/linux/xburst/patches-3.10/013-MIPS-JZ4740-Acquire-and-enable-DMA-controller-clock.patch
@@ -0,0 +1,80 @@
+From b1ab71156cd49b2389397d3be54b93fe394a1cb2 Mon Sep 17 00:00:00 2001
+From: Maarten ter Huurne <maarten@treewalker.org>
+Date: Tue, 9 Oct 2012 13:09:57 +0200
+Subject: [PATCH 13/16] MIPS: JZ4740: Acquire and enable DMA controller clock
+
+Previously, it was assumed that the DMA controller clock is not gated
+when the kernel starts running. While that is the power-on state, it is
+safer to not rely on that.
+
+Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
+---
+ arch/mips/jz4740/clock.c | 2 +-
+ arch/mips/jz4740/dma.c | 24 ++++++++++++++++++++++--
+ 2 files changed, 23 insertions(+), 3 deletions(-)
+
+diff --git a/arch/mips/jz4740/clock.c b/arch/mips/jz4740/clock.c
+index 1b5f554..b3eba60 100644
+--- a/arch/mips/jz4740/clock.c
++++ b/arch/mips/jz4740/clock.c
+@@ -921,4 +921,4 @@ static int jz4740_clock_init(void)
+
+ return 0;
+ }
+-arch_initcall(jz4740_clock_init);
++postcore_initcall(jz4740_clock_init);
+diff --git a/arch/mips/jz4740/dma.c b/arch/mips/jz4740/dma.c
+index 317ec6f..fb5266c 100644
+--- a/arch/mips/jz4740/dma.c
++++ b/arch/mips/jz4740/dma.c
+@@ -16,6 +16,7 @@
+ #include <linux/kernel.h>
+ #include <linux/module.h>
+ #include <linux/spinlock.h>
++#include <linux/clk.h>
+ #include <linux/interrupt.h>
+
+ #include <linux/dma-mapping.h>
+@@ -268,6 +269,7 @@ static irqreturn_t jz4740_dma_irq(int irq, void *dev_id)
+
+ static int jz4740_dma_init(void)
+ {
++ struct clk *clk;
+ unsigned int ret;
+
+ jz4740_dma_base = ioremap(JZ4740_DMAC_BASE_ADDR, 0x400);
+@@ -277,11 +279,29 @@ static int jz4740_dma_init(void)
+
+ spin_lock_init(&jz4740_dma_lock);
+
+- ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL);
++ clk = clk_get(NULL, "dma");
++ if (IS_ERR(clk)) {
++ ret = PTR_ERR(clk);
++ printk(KERN_ERR "JZ4740 DMA: Failed to request clock: %d\n",
++ ret);
++ goto err_iounmap;
++ }
+
+- if (ret)
++ ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL);
++ if (ret) {
+ printk(KERN_ERR "JZ4740 DMA: Failed to request irq: %d\n", ret);
++ goto err_clkput;
++ }
++
++ clk_enable(clk);
++
++ return 0;
++
++err_clkput:
++ clk_put(clk);
+
++err_iounmap:
++ iounmap(jz4740_dma_base);
+ return ret;
+ }
+ arch_initcall(jz4740_dma_init);
+--
+1.7.10.4
+