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-rw-r--r--kernel/arch/arm/mach-socfpga/pm.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-socfpga/pm.c b/kernel/arch/arm/mach-socfpga/pm.c
new file mode 100644
index 000000000..c378ab0c2
--- /dev/null
+++ b/kernel/arch/arm/mach-socfpga/pm.c
@@ -0,0 +1,149 @@
+/*
+ * arch/arm/mach-socfpga/pm.c
+ *
+ * Copyright (C) 2014-2015 Altera Corporation. All rights reserved.
+ *
+ * with code from pm-imx6.c
+ * Copyright 2011-2014 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/bitops.h>
+#include <linux/genalloc.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of_platform.h>
+#include <linux/suspend.h>
+#include <asm/suspend.h>
+#include <asm/fncpy.h>
+#include "core.h"
+
+/* Pointer to function copied to ocram */
+static u32 (*socfpga_sdram_self_refresh_in_ocram)(u32 sdr_base);
+
+static int socfpga_setup_ocram_self_refresh(void)
+{
+ struct platform_device *pdev;
+ phys_addr_t ocram_pbase;
+ struct device_node *np;
+ struct gen_pool *ocram_pool;
+ unsigned long ocram_base;
+ void __iomem *suspend_ocram_base;
+ int ret = 0;
+
+ np = of_find_compatible_node(NULL, NULL, "mmio-sram");
+ if (!np) {
+ pr_err("%s: Unable to find mmio-sram in dtb\n", __func__);
+ return -ENODEV;
+ }
+
+ pdev = of_find_device_by_node(np);
+ if (!pdev) {
+ pr_warn("%s: failed to find ocram device!\n", __func__);
+ ret = -ENODEV;
+ goto put_node;
+ }
+
+ ocram_pool = gen_pool_get(&pdev->dev, NULL);
+ if (!ocram_pool) {
+ pr_warn("%s: ocram pool unavailable!\n", __func__);
+ ret = -ENODEV;
+ goto put_node;
+ }
+
+ ocram_base = gen_pool_alloc(ocram_pool, socfpga_sdram_self_refresh_sz);
+ if (!ocram_base) {
+ pr_warn("%s: unable to alloc ocram!\n", __func__);
+ ret = -ENOMEM;
+ goto put_node;
+ }
+
+ ocram_pbase = gen_pool_virt_to_phys(ocram_pool, ocram_base);
+
+ suspend_ocram_base = __arm_ioremap_exec(ocram_pbase,
+ socfpga_sdram_self_refresh_sz,
+ false);
+ if (!suspend_ocram_base) {
+ pr_warn("%s: __arm_ioremap_exec failed!\n", __func__);
+ ret = -ENOMEM;
+ goto put_node;
+ }
+
+ /* Copy the code that puts DDR in self refresh to ocram */
+ socfpga_sdram_self_refresh_in_ocram =
+ (void *)fncpy(suspend_ocram_base,
+ &socfpga_sdram_self_refresh,
+ socfpga_sdram_self_refresh_sz);
+
+ WARN(!socfpga_sdram_self_refresh_in_ocram,
+ "could not copy function to ocram");
+ if (!socfpga_sdram_self_refresh_in_ocram)
+ ret = -EFAULT;
+
+put_node:
+ of_node_put(np);
+
+ return ret;
+}
+
+static int socfpga_pm_suspend(unsigned long arg)
+{
+ u32 ret;
+
+ if (!sdr_ctl_base_addr)
+ return -EFAULT;
+
+ ret = socfpga_sdram_self_refresh_in_ocram((u32)sdr_ctl_base_addr);
+
+ pr_debug("%s self-refresh loops request=%d exit=%d\n", __func__,
+ ret & 0xffff, (ret >> 16) & 0xffff);
+
+ return 0;
+}
+
+static int socfpga_pm_enter(suspend_state_t state)
+{
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ case PM_SUSPEND_MEM:
+ outer_disable();
+ cpu_suspend(0, socfpga_pm_suspend);
+ outer_resume();
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static const struct platform_suspend_ops socfpga_pm_ops = {
+ .valid = suspend_valid_only_mem,
+ .enter = socfpga_pm_enter,
+};
+
+static int __init socfpga_pm_init(void)
+{
+ int ret;
+
+ ret = socfpga_setup_ocram_self_refresh();
+ if (ret)
+ return ret;
+
+ suspend_set_ops(&socfpga_pm_ops);
+ pr_info("SoCFPGA initialized for DDR self-refresh during suspend.\n");
+
+ return 0;
+}
+arch_initcall(socfpga_pm_init);