From: Philipp Zabel Date: Thu, 28 Mar 2013 16:35:19 +0000 (+0100) Subject: ARM i.MX6q: Add GPU, VPU, IPU, and OpenVG resets to System Reset Controller (SRC) X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=02985b94638b4de3ef9f2eb2ac5befe5bab12c26;p=linux-beck.git ARM i.MX6q: Add GPU, VPU, IPU, and OpenVG resets to System Reset Controller (SRC) The SRC has auto-deasserting reset bits that control reset lines to the GPU, VPU, IPU, and OpenVG IP modules. This patch adds a reset controller that can be controlled by those devices using the reset controller API. Signed-off-by: Philipp Zabel Reviewed-by: Stephen Warren Reviewed-by: Marek Vasut Reviewed-by: Pavel Machek Signed-off-by: Shawn Guo --- 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 000000000000..13301777e11c --- /dev/null +++ b/Documentation/devicetree/bindings/reset/fsl,imx-src.txt @@ -0,0 +1,49 @@ +Freescale i.MX System Reset Controller +====================================== + +Please also refer to reset.txt in this directory for common reset +controller binding usage. + +Required properties: +- compatible: Should be "fsl,-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@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 resets +property, containing a phandle to the SRC device node and a +RESET_INDEX specifying which module to reset, as described in +reset.txt + +example: + + ipu1: ipu@02400000 { + resets = <&src 2>; + }; + ipu2: ipu@02800000 { + resets = <&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/Kconfig b/arch/arm/mach-imx/Kconfig index 1ab069cf722f..5b676d425bab 100644 --- a/arch/arm/mach-imx/Kconfig +++ b/arch/arm/mach-imx/Kconfig @@ -76,6 +76,7 @@ config HAVE_IMX_MMDC config HAVE_IMX_SRC def_bool y if SMP + select ARCH_HAS_RESET_CONTROLLER config IMX_HAVE_IOMUX_V1 bool diff --git a/arch/arm/mach-imx/src.c b/arch/arm/mach-imx/src.c index 09a742f8c7ab..dec641108b54 100644 --- a/arch/arm/mach-imx/src.c +++ b/arch/arm/mach-imx/src.c @@ -14,16 +14,72 @@ #include #include #include +#include #include #include #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 DEFINE_SPINLOCK(scr_lock); + +static const 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 +}; + +static int imx_src_reset_module(struct reset_controller_dev *rcdev, + unsigned long sw_reset_idx) +{ + unsigned long timeout; + unsigned long flags; + 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]; + + spin_lock_irqsave(&scr_lock, flags); + val = readl_relaxed(src_base + SRC_SCR); + val |= bit; + writel_relaxed(val, src_base + SRC_SCR); + spin_unlock_irqrestore(&scr_lock, flags); + + timeout = jiffies + msecs_to_jiffies(1000); + while (readl(src_base + SRC_SCR) & bit) { + if (time_after(jiffies, timeout)) + return -ETIME; + cpu_relax(); + } + + return 0; +} + +static struct reset_control_ops imx_src_ops = { + .reset = imx_src_reset_module, +}; + +static struct reset_controller_dev imx_reset_controller = { + .ops = &imx_src_ops, + .nr_resets = ARRAY_SIZE(sw_reset_bits), +}; void imx_enable_cpu(int cpu, bool enable) { @@ -31,9 +87,11 @@ void imx_enable_cpu(int cpu, bool enable) cpu = cpu_logical_map(cpu); mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1); + spin_lock(&scr_lock); val = readl_relaxed(src_base + SRC_SCR); val = enable ? val | mask : val & ~mask; writel_relaxed(val, src_base + SRC_SCR); + spin_unlock(&scr_lock); } void imx_set_cpu_jump(int cpu, void *jump_addr) @@ -60,9 +118,11 @@ void imx_src_prepare_restart(void) u32 val; /* clear enable bits of secondary cores */ + spin_lock(&scr_lock); val = readl_relaxed(src_base + SRC_SCR); val &= ~(0x7 << BP_SRC_SCR_CORE1_ENABLE); writel_relaxed(val, src_base + SRC_SCR); + spin_unlock(&scr_lock); /* clear persistent entry register of primary core */ writel_relaxed(0, src_base + SRC_GPR1); @@ -77,11 +137,16 @@ void __init imx_src_init(void) src_base = of_iomap(np, 0); WARN_ON(!src_base); + imx_reset_controller.of_node = np; + reset_controller_register(&imx_reset_controller); + /* * force warm reset sources to generate cold reset * for a more reliable restart */ + spin_lock(&scr_lock); val = readl_relaxed(src_base + SRC_SCR); val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE); writel_relaxed(val, src_base + SRC_SCR); + spin_unlock(&scr_lock); }