2 * arch/arm/mach-socfpga/pm.c
4 * Copyright (C) 2014-2015 Altera Corporation. All rights reserved.
6 * with code from pm-imx6.c
7 * Copyright 2011-2014 Freescale Semiconductor, Inc.
8 * Copyright 2011 Linaro Ltd.
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms and conditions of the GNU General Public License,
12 * version 2, as published by the Free Software Foundation.
14 * This program is distributed in the hope it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
19 * You should have received a copy of the GNU General Public License along with
20 * this program. If not, see <http://www.gnu.org/licenses/>.
23 #include <linux/bitops.h>
24 #include <linux/genalloc.h>
25 #include <linux/init.h>
27 #include <linux/of_platform.h>
28 #include <linux/suspend.h>
29 #include <asm/suspend.h>
30 #include <asm/fncpy.h>
33 /* Pointer to function copied to ocram */
34 static u32 (*socfpga_sdram_self_refresh_in_ocram)(u32 sdr_base);
36 static int socfpga_setup_ocram_self_refresh(void)
38 struct platform_device *pdev;
39 phys_addr_t ocram_pbase;
40 struct device_node *np;
41 struct gen_pool *ocram_pool;
42 unsigned long ocram_base;
43 void __iomem *suspend_ocram_base;
46 np = of_find_compatible_node(NULL, NULL, "mmio-sram");
48 pr_err("%s: Unable to find mmio-sram in dtb\n", __func__);
52 pdev = of_find_device_by_node(np);
54 pr_warn("%s: failed to find ocram device!\n", __func__);
59 ocram_pool = gen_pool_get(&pdev->dev, NULL);
61 pr_warn("%s: ocram pool unavailable!\n", __func__);
66 ocram_base = gen_pool_alloc(ocram_pool, socfpga_sdram_self_refresh_sz);
68 pr_warn("%s: unable to alloc ocram!\n", __func__);
73 ocram_pbase = gen_pool_virt_to_phys(ocram_pool, ocram_base);
75 suspend_ocram_base = __arm_ioremap_exec(ocram_pbase,
76 socfpga_sdram_self_refresh_sz,
78 if (!suspend_ocram_base) {
79 pr_warn("%s: __arm_ioremap_exec failed!\n", __func__);
84 /* Copy the code that puts DDR in self refresh to ocram */
85 socfpga_sdram_self_refresh_in_ocram =
86 (void *)fncpy(suspend_ocram_base,
87 &socfpga_sdram_self_refresh,
88 socfpga_sdram_self_refresh_sz);
90 WARN(!socfpga_sdram_self_refresh_in_ocram,
91 "could not copy function to ocram");
92 if (!socfpga_sdram_self_refresh_in_ocram)
101 static int socfpga_pm_suspend(unsigned long arg)
105 if (!sdr_ctl_base_addr)
108 ret = socfpga_sdram_self_refresh_in_ocram((u32)sdr_ctl_base_addr);
110 pr_debug("%s self-refresh loops request=%d exit=%d\n", __func__,
111 ret & 0xffff, (ret >> 16) & 0xffff);
116 static int socfpga_pm_enter(suspend_state_t state)
119 case PM_SUSPEND_STANDBY:
122 cpu_suspend(0, socfpga_pm_suspend);
131 static const struct platform_suspend_ops socfpga_pm_ops = {
132 .valid = suspend_valid_only_mem,
133 .enter = socfpga_pm_enter,
136 static int __init socfpga_pm_init(void)
140 ret = socfpga_setup_ocram_self_refresh();
144 suspend_set_ops(&socfpga_pm_ops);
145 pr_info("SoCFPGA initialized for DDR self-refresh during suspend.\n");
149 arch_initcall(socfpga_pm_init);