[RFC PATCH 1/5] ARM i.MX6q: Add GPU, VPU, IPU, and OpenVG resets to system reset controller
Philipp Zabel
p.zabel at pengutronix.de
Wed Jan 9 12:17:15 EST 2013
Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
---
.../devicetree/bindings/reset/fsl,imx-src.txt | 45 ++++++++++++++++++++
arch/arm/mach-imx/src.c | 41 ++++++++++++++++++
include/linux/imx-src.h | 6 +++
3 files changed, 92 insertions(+)
create mode 100644 Documentation/devicetree/bindings/reset/fsl,imx-src.txt
create mode 100644 include/linux/imx-src.h
diff --git a/Documentation/devicetree/bindings/reset/fsl,imx-src.txt b/Documentation/devicetree/bindings/reset/fsl,imx-src.txt
new file mode 100644
index 0000000..8f1e66a
--- /dev/null
+++ b/Documentation/devicetree/bindings/reset/fsl,imx-src.txt
@@ -0,0 +1,45 @@
+Freescale i.MX System Reset Controller
+======================================
+
+Required properties:
+- compatible: Should be "fsl,<chip>-src"
+- reg: should be register base and length as documented in the
+ datasheet
+- interrupts: Should contain SRC interrupt and CPU WDOG interrupt,
+ in this order.
+- #reset-cells: 1, see below
+
+example:
+
+src: src at 020d8000 {
+ compatible = "fsl,imx6q-src";
+ reg = <0x020d8000 0x4000>;
+ interrupts = <0 91 0x04 0 96 0x04>;
+ #reset-cells = <1>;
+};
+
+Specifying reset lines connected to IP modules
+==============================================
+
+The system reset controller can be used to reset the GPU, VPU,
+IPU, and OpenVG IP modules on i.MX5 and i.MX6 ICs. Those device
+nodes should specify the reset line on the SRC in their reset
+property, containing a phandle to the SRC device node and a
+RESET_INDEX specifying which module to reset.
+
+example:
+
+ ipu0: ipu0 {
+ reset = <&src 2>;
+ };
+ ipu1: ipu1 {
+ reset = <&src 4>;
+ };
+
+The following RESET_INDEX values are valid for i.MX5:
+GPU_RESET 0
+VPU_RESET 1
+IPU1_RESET 2
+OPEN_VG_RESET 3
+The following additional RESET_INDEX value is valid for i.MX6:
+IPU2_RESET 4
diff --git a/arch/arm/mach-imx/src.c b/arch/arm/mach-imx/src.c
index e15f155..10658b4 100644
--- a/arch/arm/mach-imx/src.c
+++ b/arch/arm/mach-imx/src.c
@@ -20,11 +20,52 @@
#define SRC_SCR 0x000
#define SRC_GPR1 0x020
#define BP_SRC_SCR_WARM_RESET_ENABLE 0
+#define BP_SRC_SCR_SW_GPU_RST 1
+#define BP_SRC_SCR_SW_VPU_RST 2
+#define BP_SRC_SCR_SW_IPU1_RST 3
+#define BP_SRC_SCR_SW_OPEN_VG_RST 4
+#define BP_SRC_SCR_SW_IPU2_RST 12
#define BP_SRC_SCR_CORE1_RST 14
#define BP_SRC_SCR_CORE1_ENABLE 22
static void __iomem *src_base;
+static int sw_reset_bits[5] = {
+ BP_SRC_SCR_SW_GPU_RST,
+ BP_SRC_SCR_SW_VPU_RST,
+ BP_SRC_SCR_SW_IPU1_RST,
+ BP_SRC_SCR_SW_OPEN_VG_RST,
+ BP_SRC_SCR_SW_IPU2_RST
+};
+
+int imx_src_reset(int sw_reset_idx)
+{
+ unsigned long timeout;
+ int bit;
+ u32 val;
+
+ if (!src_base)
+ return -ENODEV;
+
+ if (sw_reset_idx >= ARRAY_SIZE(sw_reset_bits))
+ return -EINVAL;
+
+ bit = 1 << sw_reset_bits[sw_reset_idx];
+
+ val = readl_relaxed(src_base + SRC_SCR);
+ val |= bit;
+ writel_relaxed(val, src_base + SRC_SCR);
+
+ timeout = jiffies + msecs_to_jiffies(1000);
+ while (readl(src_base + SRC_SCR) & bit) {
+ if (time_after(jiffies, timeout))
+ return -ETIME;
+ cpu_relax();
+ }
+
+ return 0;
+}
+
void imx_enable_cpu(int cpu, bool enable)
{
u32 mask, val;
diff --git a/include/linux/imx-src.h b/include/linux/imx-src.h
new file mode 100644
index 0000000..b93ed96
--- /dev/null
+++ b/include/linux/imx-src.h
@@ -0,0 +1,6 @@
+#ifndef __IMX_SRC_H__
+#define __IMX_SRC_H__
+
+extern int imx_src_reset(int sw_reset_idx);
+
+#endif /* __IMX_SRC_H__ */
--
1.7.10.4
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