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-rw-r--r--kernel/arch/arm/mach-mvebu/pm-board.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-mvebu/pm-board.c b/kernel/arch/arm/mach-mvebu/pm-board.c
new file mode 100644
index 000000000..301ab38d3
--- /dev/null
+++ b/kernel/arch/arm/mach-mvebu/pm-board.c
@@ -0,0 +1,144 @@
+/*
+ * Board-level suspend/resume support.
+ *
+ * Copyright (C) 2014 Marvell
+ *
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_gpio.h>
+#include <linux/slab.h>
+#include "common.h"
+
+#define ARMADA_XP_GP_PIC_NR_GPIOS 3
+
+static void __iomem *gpio_ctrl;
+static int pic_gpios[ARMADA_XP_GP_PIC_NR_GPIOS];
+static int pic_raw_gpios[ARMADA_XP_GP_PIC_NR_GPIOS];
+
+static void mvebu_armada_xp_gp_pm_enter(void __iomem *sdram_reg, u32 srcmd)
+{
+ u32 reg, ackcmd;
+ int i;
+
+ /* Put 001 as value on the GPIOs */
+ reg = readl(gpio_ctrl);
+ for (i = 0; i < ARMADA_XP_GP_PIC_NR_GPIOS; i++)
+ reg &= ~BIT(pic_raw_gpios[i]);
+ reg |= BIT(pic_raw_gpios[0]);
+ writel(reg, gpio_ctrl);
+
+ /* Prepare writing 111 to the GPIOs */
+ ackcmd = readl(gpio_ctrl);
+ for (i = 0; i < ARMADA_XP_GP_PIC_NR_GPIOS; i++)
+ ackcmd |= BIT(pic_raw_gpios[i]);
+
+ srcmd = cpu_to_le32(srcmd);
+ ackcmd = cpu_to_le32(ackcmd);
+
+ /*
+ * Wait a while, the PIC needs quite a bit of time between the
+ * two GPIO commands.
+ */
+ mdelay(3000);
+
+ asm volatile (
+ /* Align to a cache line */
+ ".balign 32\n\t"
+
+ /* Enter self refresh */
+ "str %[srcmd], [%[sdram_reg]]\n\t"
+
+ /*
+ * Wait 100 cycles for DDR to enter self refresh, by
+ * doing 50 times two instructions.
+ */
+ "mov r1, #50\n\t"
+ "1: subs r1, r1, #1\n\t"
+ "bne 1b\n\t"
+
+ /* Issue the command ACK */
+ "str %[ackcmd], [%[gpio_ctrl]]\n\t"
+
+ /* Trap the processor */
+ "b .\n\t"
+ : : [srcmd] "r" (srcmd), [sdram_reg] "r" (sdram_reg),
+ [ackcmd] "r" (ackcmd), [gpio_ctrl] "r" (gpio_ctrl) : "r1");
+}
+
+static int mvebu_armada_xp_gp_pm_init(void)
+{
+ struct device_node *np;
+ struct device_node *gpio_ctrl_np;
+ int ret = 0, i;
+
+ if (!of_machine_is_compatible("marvell,axp-gp"))
+ return -ENODEV;
+
+ np = of_find_node_by_name(NULL, "pm_pic");
+ if (!np)
+ return -ENODEV;
+
+ for (i = 0; i < ARMADA_XP_GP_PIC_NR_GPIOS; i++) {
+ char *name;
+ struct of_phandle_args args;
+
+ pic_gpios[i] = of_get_named_gpio(np, "ctrl-gpios", i);
+ if (pic_gpios[i] < 0) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ name = kasprintf(GFP_KERNEL, "pic-pin%d", i);
+ if (!name) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = gpio_request(pic_gpios[i], name);
+ if (ret < 0) {
+ kfree(name);
+ goto out;
+ }
+
+ ret = gpio_direction_output(pic_gpios[i], 0);
+ if (ret < 0) {
+ gpio_free(pic_gpios[i]);
+ kfree(name);
+ goto out;
+ }
+
+ ret = of_parse_phandle_with_fixed_args(np, "ctrl-gpios", 2,
+ i, &args);
+ if (ret < 0) {
+ gpio_free(pic_gpios[i]);
+ kfree(name);
+ goto out;
+ }
+
+ gpio_ctrl_np = args.np;
+ pic_raw_gpios[i] = args.args[0];
+ }
+
+ gpio_ctrl = of_iomap(gpio_ctrl_np, 0);
+ if (!gpio_ctrl)
+ return -ENOMEM;
+
+ mvebu_pm_init(mvebu_armada_xp_gp_pm_enter);
+
+out:
+ of_node_put(np);
+ return ret;
+}
+
+late_initcall(mvebu_armada_xp_gp_pm_init);