/* * 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);