1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * arch/arm/mach-socfpga/pm.c 4 * 5 * Copyright (C) 2014-2015 Altera Corporation. All rights reserved. 6 * 7 * with code from pm-imx6.c 8 * Copyright 2011-2014 Freescale Semiconductor, Inc. 9 * Copyright 2011 Linaro Ltd. 10 */ 11 12 #include <linux/bitops.h> 13 #include <linux/genalloc.h> 14 #include <linux/init.h> 15 #include <linux/io.h> 16 #include <linux/of.h> 17 #include <linux/of_platform.h> 18 #include <linux/platform_device.h> 19 #include <linux/suspend.h> 20 #include <asm/suspend.h> 21 #include <asm/fncpy.h> 22 #include "core.h" 23 24 /* Pointer to function copied to ocram */ 25 static u32 (*socfpga_sdram_self_refresh_in_ocram)(u32 sdr_base); 26 27 static int socfpga_setup_ocram_self_refresh(void) 28 { 29 struct platform_device *pdev; 30 phys_addr_t ocram_pbase; 31 struct device_node *np; 32 struct gen_pool *ocram_pool; 33 unsigned long ocram_base; 34 void __iomem *suspend_ocram_base; 35 int ret = 0; 36 37 np = of_find_compatible_node(NULL, NULL, "mmio-sram"); 38 if (!np) { 39 pr_err("%s: Unable to find mmio-sram in dtb\n", __func__); 40 return -ENODEV; 41 } 42 43 pdev = of_find_device_by_node(np); 44 if (!pdev) { 45 pr_warn("%s: failed to find ocram device!\n", __func__); 46 ret = -ENODEV; 47 goto put_node; 48 } 49 50 ocram_pool = gen_pool_get(&pdev->dev, NULL); 51 if (!ocram_pool) { 52 pr_warn("%s: ocram pool unavailable!\n", __func__); 53 ret = -ENODEV; 54 goto put_device; 55 } 56 57 ocram_base = gen_pool_alloc(ocram_pool, socfpga_sdram_self_refresh_sz); 58 if (!ocram_base) { 59 pr_warn("%s: unable to alloc ocram!\n", __func__); 60 ret = -ENOMEM; 61 goto put_device; 62 } 63 64 ocram_pbase = gen_pool_virt_to_phys(ocram_pool, ocram_base); 65 66 suspend_ocram_base = __arm_ioremap_exec(ocram_pbase, 67 socfpga_sdram_self_refresh_sz, 68 false); 69 if (!suspend_ocram_base) { 70 pr_warn("%s: __arm_ioremap_exec failed!\n", __func__); 71 ret = -ENOMEM; 72 goto put_device; 73 } 74 75 /* Copy the code that puts DDR in self refresh to ocram */ 76 socfpga_sdram_self_refresh_in_ocram = 77 (void *)fncpy(suspend_ocram_base, 78 &socfpga_sdram_self_refresh, 79 socfpga_sdram_self_refresh_sz); 80 81 WARN(!socfpga_sdram_self_refresh_in_ocram, 82 "could not copy function to ocram"); 83 if (!socfpga_sdram_self_refresh_in_ocram) 84 ret = -EFAULT; 85 86 put_device: 87 put_device(&pdev->dev); 88 put_node: 89 of_node_put(np); 90 91 return ret; 92 } 93 94 static int socfpga_pm_suspend(unsigned long arg) 95 { 96 u32 ret; 97 98 if (!sdr_ctl_base_addr) 99 return -EFAULT; 100 101 ret = socfpga_sdram_self_refresh_in_ocram((u32)sdr_ctl_base_addr); 102 103 pr_debug("%s self-refresh loops request=%d exit=%d\n", __func__, 104 ret & 0xffff, (ret >> 16) & 0xffff); 105 106 return 0; 107 } 108 109 static int socfpga_pm_enter(suspend_state_t state) 110 { 111 switch (state) { 112 case PM_SUSPEND_MEM: 113 outer_disable(); 114 cpu_suspend(0, socfpga_pm_suspend); 115 outer_resume(); 116 break; 117 default: 118 return -EINVAL; 119 } 120 return 0; 121 } 122 123 static const struct platform_suspend_ops socfpga_pm_ops = { 124 .valid = suspend_valid_only_mem, 125 .enter = socfpga_pm_enter, 126 }; 127 128 static int __init socfpga_pm_init(void) 129 { 130 int ret; 131 132 ret = socfpga_setup_ocram_self_refresh(); 133 if (ret) 134 return ret; 135 136 suspend_set_ops(&socfpga_pm_ops); 137 pr_info("SoCFPGA initialized for DDR self-refresh during suspend.\n"); 138 139 return 0; 140 } 141 arch_initcall(socfpga_pm_init); 142