/* * Suspend/resume support. Currently supporting Armada XP only. * * 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/cpu_pm.h> #include <linux/delay.h> #include <linux/gpio.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mbus.h> #include <linux/of_address.h> #include <linux/suspend.h> #include <asm/cacheflush.h> #include <asm/outercache.h> #include <asm/suspend.h> #include "coherency.h" #include "common.h" #include "pmsu.h" #define SDRAM_CONFIG_OFFS 0x0 #define SDRAM_CONFIG_SR_MODE_BIT BIT(24) #define SDRAM_OPERATION_OFFS 0x18 #define SDRAM_OPERATION_SELF_REFRESH 0x7 #define SDRAM_DLB_EVICTION_OFFS 0x30c #define SDRAM_DLB_EVICTION_THRESHOLD_MASK 0xff static void (*mvebu_board_pm_enter)(void __iomem *sdram_reg, u32 srcmd); static void __iomem *sdram_ctrl; static int mvebu_pm_powerdown(unsigned long data) { u32 reg, srcmd; flush_cache_all(); outer_flush_all(); /* * Issue a Data Synchronization Barrier instruction to ensure * that all state saving has been completed. */ dsb(); /* Flush the DLB and wait ~7 usec */ reg = readl(sdram_ctrl + SDRAM_DLB_EVICTION_OFFS); reg &= ~SDRAM_DLB_EVICTION_THRESHOLD_MASK; writel(reg, sdram_ctrl + SDRAM_DLB_EVICTION_OFFS); udelay(7); /* Set DRAM in battery backup mode */ reg = readl(sdram_ctrl + SDRAM_CONFIG_OFFS); reg &= ~SDRAM_CONFIG_SR_MODE_BIT; writel(reg, sdram_ctrl + SDRAM_CONFIG_OFFS); /* Prepare to go to self-refresh */ srcmd = readl(sdram_ctrl + SDRAM_OPERATION_OFFS); srcmd &= ~0x1F; srcmd |= SDRAM_OPERATION_SELF_REFRESH; mvebu_board_pm_enter(sdram_ctrl + SDRAM_OPERATION_OFFS, srcmd); return 0; } #define BOOT_INFO_ADDR 0x3000 #define BOOT_MAGIC_WORD 0xdeadb002 #define BOOT_MAGIC_LIST_END 0xffffffff /* * Those registers are accessed before switching the internal register * base, which is why we hardcode the 0xd0000000 base address, the one * used by the SoC out of reset. */ #define MBUS_WINDOW_12_CTRL 0xd00200b0 #define MBUS_INTERNAL_REG_ADDRESS 0xd0020080 #define SDRAM_WIN_BASE_REG(x) (0x20180 + (0x8*x)) #define SDRAM_WIN_CTRL_REG(x) (0x20184 + (0x8*x)) static phys_addr_t mvebu_internal_reg_base(void) { struct device_node *np; __be32 in_addr[2]; np = of_find_node_by_name(NULL, "internal-regs"); BUG_ON(!np); /* * Ask the DT what is the internal register address on this * platform. In the mvebu-mbus DT binding, 0xf0010000 * corresponds to the internal register window. */ in_addr[0] = cpu_to_be32(0xf0010000); in_addr[1] = 0x0; return of_translate_address(np, in_addr); } static void mvebu_pm_store_armadaxp_bootinfo(u32 *store_addr) { phys_addr_t resume_pc; resume_pc = __pa_symbol(armada_370_xp_cpu_resume); /* * The bootloader expects the first two words to be a magic * value (BOOT_MAGIC_WORD), followed by the address of the * resume code to jump to. Then, it expects a sequence of * (address, value) pairs, which can be used to restore the * value of certain registers. This sequence must end with the * BOOT_MAGIC_LIST_END magic value. */ writel(BOOT_MAGIC_WORD, store_addr++); writel(resume_pc, store_addr++); /* * Some platforms remap their internal register base address * to 0xf1000000. However, out of reset, window 12 starts at * 0xf0000000 and ends at 0xf7ffffff, which would overlap with * the internal registers. Therefore, disable window 12. */ writel(MBUS_WINDOW_12_CTRL, store_addr++); writel(0x0, store_addr++); /* * Set the internal register base address to the value * expected by Linux, as read from the Device Tree. */ writel(MBUS_INTERNAL_REG_ADDRESS, store_addr++); writel(mvebu_internal_reg_base(), store_addr++); /* * Ask the mvebu-mbus driver to store the SDRAM window * configuration, which has to be restored by the bootloader * before re-entering the kernel on resume. */ store_addr += mvebu_mbus_save_cpu_target(store_addr); writel(BOOT_MAGIC_LIST_END, store_addr); } static int mvebu_pm_store_bootinfo(void) { u32 *store_addr; store_addr = phys_to_virt(BOOT_INFO_ADDR); if (of_machine_is_compatible("marvell,armadaxp")) mvebu_pm_store_armadaxp_bootinfo(store_addr); else return -ENODEV; return 0; } static int mvebu_enter_suspend(void) { int ret; ret = mvebu_pm_store_bootinfo(); if (ret) return ret; cpu_pm_enter(); cpu_suspend(0, mvebu_pm_powerdown); outer_resume(); mvebu_v7_pmsu_idle_exit(); set_cpu_coherent(); cpu_pm_exit(); return 0; } static int mvebu_pm_enter(suspend_state_t state) { switch (state) { case PM_SUSPEND_STANDBY: cpu_do_idle(); break; case PM_SUSPEND_MEM: pr_warn("Entering suspend to RAM. Only special wake-up sources will resume the system\n"); return mvebu_enter_suspend(); default: return -EINVAL; } return 0; } static int mvebu_pm_valid(suspend_state_t state) { if (state == PM_SUSPEND_STANDBY) return 1; if (state == PM_SUSPEND_MEM && mvebu_board_pm_enter != NULL) return 1; return 0; } static const struct platform_suspend_ops mvebu_pm_ops = { .enter = mvebu_pm_enter, .valid = mvebu_pm_valid, }; static int __init mvebu_pm_init(void) { if (!of_machine_is_compatible("marvell,armadaxp") && !of_machine_is_compatible("marvell,armada370") && !of_machine_is_compatible("marvell,armada380") && !of_machine_is_compatible("marvell,armada390")) return -ENODEV; suspend_set_ops(&mvebu_pm_ops); return 0; } late_initcall(mvebu_pm_init); int __init mvebu_pm_suspend_init(void (*board_pm_enter)(void __iomem *sdram_reg, u32 srcmd)) { struct device_node *np; struct resource res; np = of_find_compatible_node(NULL, NULL, "marvell,armada-xp-sdram-controller"); if (!np) return -ENODEV; if (of_address_to_resource(np, 0, &res)) { of_node_put(np); return -ENODEV; } if (!request_mem_region(res.start, resource_size(&res), np->full_name)) { of_node_put(np); return -EBUSY; } sdram_ctrl = ioremap(res.start, resource_size(&res)); if (!sdram_ctrl) { release_mem_region(res.start, resource_size(&res)); of_node_put(np); return -ENOMEM; } of_node_put(np); mvebu_board_pm_enter = board_pm_enter; return 0; }