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Diffstat (limited to 'arch/arm/mach-imx/src.c')
| -rw-r--r-- | arch/arm/mach-imx/src.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/src.c b/arch/arm/mach-imx/src.c new file mode 100644 index 000000000..59a8e8cc4 --- /dev/null +++ b/arch/arm/mach-imx/src.c @@ -0,0 +1,238 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2011 Freescale Semiconductor, Inc. + * Copyright 2011 Linaro Ltd. + */ + +#include <linux/init.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/smp.h> +#include <asm/smp_plat.h> +#include "common.h" +#include "hardware.h" + +#define SRC_SCR 0x000 +#define SRC_GPR1_V1 0x020 +#define SRC_GPR1_V2 0x074 +#define SRC_GPR1(gpr_v2) ((gpr_v2) ? SRC_GPR1_V2 : SRC_GPR1_V1) +#define BP_SRC_SCR_WARM_RESET_ENABLE 0 +#define BP_SRC_SCR_SW_GPU_RST 1 +#define BP_SRC_SCR_SW_VPU_RST 2 +#define BP_SRC_SCR_SW_IPU1_RST 3 +#define BP_SRC_SCR_SW_OPEN_VG_RST 4 +#define BP_SRC_SCR_SW_IPU2_RST 12 +#define BP_SRC_SCR_CORE1_RST 14 +#define BP_SRC_SCR_CORE1_ENABLE 22 +/* below is for i.MX7D */ +#define SRC_A7RCR1 0x008 +#define BP_SRC_A7RCR1_A7_CORE1_ENABLE 1 +#define GPC_CPU_PGC_SW_PUP_REQ 0xf0 +#define GPC_CPU_PGC_SW_PDN_REQ 0xfc +#define GPC_PGC_C1 0x840 +#define BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7 0x2 + +static void __iomem *src_base; +static DEFINE_SPINLOCK(scr_lock); +static bool gpr_v2; +static void __iomem *gpc_base; + +static const int sw_reset_bits[5] = { + BP_SRC_SCR_SW_GPU_RST, + BP_SRC_SCR_SW_VPU_RST, + BP_SRC_SCR_SW_IPU1_RST, + BP_SRC_SCR_SW_OPEN_VG_RST, + BP_SRC_SCR_SW_IPU2_RST +}; + +static int imx_src_reset_module(struct reset_controller_dev *rcdev, + unsigned long sw_reset_idx) +{ + unsigned long timeout; + unsigned long flags; + int bit; + u32 val; + + if (sw_reset_idx >= ARRAY_SIZE(sw_reset_bits)) + return -EINVAL; + + bit = 1 << sw_reset_bits[sw_reset_idx]; + + spin_lock_irqsave(&scr_lock, flags); + val = readl_relaxed(src_base + SRC_SCR); + val |= bit; + writel_relaxed(val, src_base + SRC_SCR); + spin_unlock_irqrestore(&scr_lock, flags); + + timeout = jiffies + msecs_to_jiffies(1000); + while (readl(src_base + SRC_SCR) & bit) { + if (time_after(jiffies, timeout)) + return -ETIME; + cpu_relax(); + } + + return 0; +} + +static const struct reset_control_ops imx_src_ops = { + .reset = imx_src_reset_module, +}; + +static void imx_gpcv2_set_m_core_pgc(bool enable, u32 offset) +{ + writel_relaxed(enable, gpc_base + offset); +} + +/* + * The motivation for bringing up the second i.MX7D core inside the kernel + * is that legacy vendor bootloaders usually do not implement PSCI support. + * This is a significant blocker for systems in the field that are running old + * bootloader versions to upgrade to a modern mainline kernel version, as only + * one CPU of the i.MX7D would be brought up. + * Bring up the second i.MX7D core inside the kernel to make the migration + * path to mainline kernel easier for the existing iMX7D users. + */ +void imx_gpcv2_set_core1_pdn_pup_by_software(bool pdn) +{ + u32 reg = pdn ? GPC_CPU_PGC_SW_PDN_REQ : GPC_CPU_PGC_SW_PUP_REQ; + u32 val, pup; + int ret; + + imx_gpcv2_set_m_core_pgc(true, GPC_PGC_C1); + val = readl_relaxed(gpc_base + reg); + val |= BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7; + writel_relaxed(val, gpc_base + reg); + + ret = readl_relaxed_poll_timeout_atomic(gpc_base + reg, pup, + !(pup & BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7), + 5, 1000000); + if (ret < 0) { + pr_err("i.MX7D: CORE1_A7 power up timeout\n"); + val &= ~BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7; + writel_relaxed(val, gpc_base + reg); + } + + imx_gpcv2_set_m_core_pgc(false, GPC_PGC_C1); +} + +void imx_enable_cpu(int cpu, bool enable) +{ + u32 mask, val; + + cpu = cpu_logical_map(cpu); + spin_lock(&scr_lock); + if (gpr_v2) { + if (enable) + imx_gpcv2_set_core1_pdn_pup_by_software(false); + + mask = 1 << (BP_SRC_A7RCR1_A7_CORE1_ENABLE + cpu - 1); + val = readl_relaxed(src_base + SRC_A7RCR1); + val = enable ? val | mask : val & ~mask; + writel_relaxed(val, src_base + SRC_A7RCR1); + } else { + mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1); + val = readl_relaxed(src_base + SRC_SCR); + val = enable ? val | mask : val & ~mask; + val |= 1 << (BP_SRC_SCR_CORE1_RST + cpu - 1); + writel_relaxed(val, src_base + SRC_SCR); + } + spin_unlock(&scr_lock); +} + +void imx_set_cpu_jump(int cpu, void *jump_addr) +{ + cpu = cpu_logical_map(cpu); + writel_relaxed(__pa_symbol(jump_addr), + src_base + SRC_GPR1(gpr_v2) + cpu * 8); +} + +u32 imx_get_cpu_arg(int cpu) +{ + cpu = cpu_logical_map(cpu); + return readl_relaxed(src_base + SRC_GPR1(gpr_v2) + cpu * 8 + 4); +} + +void imx_set_cpu_arg(int cpu, u32 arg) +{ + cpu = cpu_logical_map(cpu); + writel_relaxed(arg, src_base + SRC_GPR1(gpr_v2) + cpu * 8 + 4); +} + +void __init imx_src_init(void) +{ + struct device_node *np; + u32 val; + + np = of_find_compatible_node(NULL, NULL, "fsl,imx51-src"); + if (!np) + return; + src_base = of_iomap(np, 0); + WARN_ON(!src_base); + + /* + * force warm reset sources to generate cold reset + * for a more reliable restart + */ + spin_lock(&scr_lock); + val = readl_relaxed(src_base + SRC_SCR); + val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE); + writel_relaxed(val, src_base + SRC_SCR); + spin_unlock(&scr_lock); +} + +void __init imx7_src_init(void) +{ + struct device_node *np; + + gpr_v2 = true; + + np = of_find_compatible_node(NULL, NULL, "fsl,imx7d-src"); + if (!np) + return; + + src_base = of_iomap(np, 0); + if (!src_base) + return; + + np = of_find_compatible_node(NULL, NULL, "fsl,imx7d-gpc"); + if (!np) + return; + + gpc_base = of_iomap(np, 0); + if (!gpc_base) + return; +} + +static const struct of_device_id imx_src_dt_ids[] = { + { .compatible = "fsl,imx51-src" }, + { /* sentinel */ } +}; + +static int imx_src_probe(struct platform_device *pdev) +{ + struct reset_controller_dev *rcdev; + + rcdev = devm_kzalloc(&pdev->dev, sizeof(*rcdev), GFP_KERNEL); + if (!rcdev) + return -ENOMEM; + + rcdev->ops = &imx_src_ops; + rcdev->dev = &pdev->dev; + rcdev->of_node = pdev->dev.of_node; + rcdev->nr_resets = ARRAY_SIZE(sw_reset_bits); + + return devm_reset_controller_register(&pdev->dev, rcdev); +} + +static struct platform_driver imx_src_driver = { + .driver = { + .name = "imx-src", + .of_match_table = imx_src_dt_ids, + }, + .probe = imx_src_probe, +}; +builtin_platform_driver(imx_src_driver); |