Initial commit

arch/arm/mach-imx/src.c

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/reset-controller.h>
+#include <linux/smp.h>
+#include <asm/smp_plat.h>
+#include "common.h"
+
+#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)
+{
+	u32 mask, val;
+
+	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)
+{
+	cpu = cpu_logical_map(cpu);
+	writel_relaxed(virt_to_phys(jump_addr),
+		       src_base + SRC_GPR1 + cpu * 8);
+}
+
+u32 imx_get_cpu_arg(int cpu)
+{
+	cpu = cpu_logical_map(cpu);
+	return readl_relaxed(src_base + SRC_GPR1 + cpu * 8 + 4);
+}
+
+void imx_set_cpu_arg(int cpu, u32 arg)
+{
+	cpu = cpu_logical_map(cpu);
+	writel_relaxed(arg, src_base + SRC_GPR1 + cpu * 8 + 4);
+}
+
+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);
+}
+
+void __init imx_src_init(void)
+{
+	struct device_node *np;
+	u32 val;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,imx51-src");
+	if (!np)
+		return;
+	src_base = of_iomap(np, 0);
+	WARN_ON(!src_base);
+
+	imx_reset_controller.of_node = np;
+	if (IS_ENABLED(CONFIG_RESET_CONTROLLER))
+		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);
+}