root/arch/arm/mach-vt8500/vt8500.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  arch/arm/mach-vt8500/vt8500.c
 *
 *  Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
 */

#include <linux/io.h>
#include <linux/pm.h>
#include <linux/reboot.h>

#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/time.h>
#include <asm/mach/map.h>

#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>

#define LEGACY_GPIO_BASE        0xD8110000
#define LEGACY_PMC_BASE         0xD8130000

/* Registers in GPIO Controller */
#define VT8500_GPIO_MUX_REG     0x200

/* Registers in Power Management Controller */
#define VT8500_HCR_REG          0x12
#define VT8500_PMSR_REG         0x60

static void __iomem *pmc_base;

static void vt8500_restart(enum reboot_mode mode, const char *cmd)
{
        if (pmc_base)
                writel(1, pmc_base + VT8500_PMSR_REG);
}

static struct map_desc vt8500_io_desc[] __initdata = {
        /* SoC MMIO registers */
        [0] = {
                .virtual        = 0xf8000000,
                .pfn            = __phys_to_pfn(0xd8000000),
                .length         = 0x00390000, /* max of all chip variants */
                .type           = MT_DEVICE
        },
};

static void __init vt8500_map_io(void)
{
        iotable_init(vt8500_io_desc, ARRAY_SIZE(vt8500_io_desc));
}

static void vt8500_power_off(void)
{
        local_irq_disable();
        writew(5, pmc_base + VT8500_HCR_REG);
        asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (0));
}

static void __init vt8500_init(void)
{
        struct device_node *np;
#if defined(CONFIG_FB_VT8500) || defined(CONFIG_FB_WM8505)
        struct device_node *fb;
        void __iomem *gpio_base;
#endif

#ifdef CONFIG_FB_VT8500
        fb = of_find_compatible_node(NULL, NULL, "via,vt8500-fb");
        if (fb) {
                np = of_find_compatible_node(NULL, NULL, "via,vt8500-gpio");
                if (np) {
                        gpio_base = of_iomap(np, 0);

                        if (!gpio_base)
                                pr_err("%s: of_iomap(gpio_mux) failed\n",
                                                                __func__);

                        of_node_put(np);
                } else {
                        gpio_base = ioremap(LEGACY_GPIO_BASE, 0x1000);
                        if (!gpio_base)
                                pr_err("%s: ioremap(legacy_gpio_mux) failed\n",
                                                                __func__);
                }
                if (gpio_base) {
                        writel(readl(gpio_base + VT8500_GPIO_MUX_REG) | 1,
                                gpio_base + VT8500_GPIO_MUX_REG);
                        iounmap(gpio_base);
                } else
                        pr_err("%s: Could not remap GPIO mux\n", __func__);

                of_node_put(fb);
        }
#endif

#ifdef CONFIG_FB_WM8505
        fb = of_find_compatible_node(NULL, NULL, "wm,wm8505-fb");
        if (fb) {
                np = of_find_compatible_node(NULL, NULL, "wm,wm8505-gpio");
                if (!np)
                        np = of_find_compatible_node(NULL, NULL,
                                                        "wm,wm8650-gpio");
                if (np) {
                        gpio_base = of_iomap(np, 0);

                        if (!gpio_base)
                                pr_err("%s: of_iomap(gpio_mux) failed\n",
                                                                __func__);

                        of_node_put(np);
                } else {
                        gpio_base = ioremap(LEGACY_GPIO_BASE, 0x1000);
                        if (!gpio_base)
                                pr_err("%s: ioremap(legacy_gpio_mux) failed\n",
                                                                __func__);
                }
                if (gpio_base) {
                        writel(readl(gpio_base + VT8500_GPIO_MUX_REG) |
                                0x80000000, gpio_base + VT8500_GPIO_MUX_REG);
                        iounmap(gpio_base);
                } else
                        pr_err("%s: Could not remap GPIO mux\n", __func__);

                of_node_put(fb);
        }
#endif

        np = of_find_compatible_node(NULL, NULL, "via,vt8500-pmc");
        if (np) {
                pmc_base = of_iomap(np, 0);

                if (!pmc_base)
                        pr_err("%s:of_iomap(pmc) failed\n", __func__);

                of_node_put(np);
        } else {
                pmc_base = ioremap(LEGACY_PMC_BASE, 0x1000);
                if (!pmc_base)
                        pr_err("%s:ioremap(power_off) failed\n", __func__);
        }
        if (pmc_base)
                register_platform_power_off(vt8500_power_off);
        else
                pr_err("%s: PMC Hibernation register could not be remapped, not enabling power off!\n", __func__);
}

static const char * const vt8500_dt_compat[] = {
        "via,vt8500",
        "wm,wm8650",
        "wm,wm8505",
        "wm,wm8750",
        "wm,wm8850",
        NULL
};

DT_MACHINE_START(WMT_DT, "VIA/Wondermedia SoC (Device Tree Support)")
        .dt_compat      = vt8500_dt_compat,
        .map_io         = vt8500_map_io,
        .init_machine   = vt8500_init,
        .restart        = vt8500_restart,
MACHINE_END