// SPDX-License-Identifier: GPL-2.0
/*
 * Renesas Technology Europe SDK7786 Support.
 *
 * Copyright (C) 2010  Matt Fleming
 * Copyright (C) 2010  Paul Mundt
 */
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/regulator/fixed.h>
#include <linux/regulator/machine.h>
#include <linux/smsc911x.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <mach/fpga.h>
#include <mach/irq.h>
#include <asm/machvec.h>
#include <asm/heartbeat.h>
#include <linux/sizes.h>
#include <asm/clock.h>
#include <asm/reboot.h>
#include <asm/smp-ops.h>

static struct resource heartbeat_resource = {
        .start          = 0x07fff8b0,
        .end            = 0x07fff8b0 + sizeof(u16) - 1,
        .flags          = IORESOURCE_MEM | IORESOURCE_MEM_16BIT,
};

static struct platform_device heartbeat_device = {
        .name           = "heartbeat",
        .id             = -1,
        .num_resources  = 1,
        .resource       = &heartbeat_resource,
};

/* Dummy supplies, where voltage doesn't matter */
static struct regulator_consumer_supply dummy_supplies[] = {
        REGULATOR_SUPPLY("vddvario", "smsc911x"),
        REGULATOR_SUPPLY("vdd33a", "smsc911x"),
};

static struct resource smsc911x_resources[] = {
        [0] = {
                .name           = "smsc911x-memory",
                .start          = 0x07ffff00,
                .end            = 0x07ffff00 + SZ_256 - 1,
                .flags          = IORESOURCE_MEM,
        },
        [1] = {
                .name           = "smsc911x-irq",
                .start          = evt2irq(0x2c0),
                .end            = evt2irq(0x2c0),
                .flags          = IORESOURCE_IRQ,
        },
};

static struct smsc911x_platform_config smsc911x_config = {
        .irq_polarity   = SMSC911X_IRQ_POLARITY_ACTIVE_LOW,
        .irq_type       = SMSC911X_IRQ_TYPE_OPEN_DRAIN,
        .flags          = SMSC911X_USE_32BIT,
        .phy_interface  = PHY_INTERFACE_MODE_MII,
};

static struct platform_device smsc911x_device = {
        .name           = "smsc911x",
        .id             = -1,
        .num_resources  = ARRAY_SIZE(smsc911x_resources),
        .resource       = smsc911x_resources,
        .dev = {
                .platform_data = &smsc911x_config,
        },
};

static struct resource smbus_fpga_resource = {
        .start          = 0x07fff9e0,
        .end            = 0x07fff9e0 + SZ_32 - 1,
        .flags          = IORESOURCE_MEM,
};

static struct platform_device smbus_fpga_device = {
        .name           = "i2c-sdk7786",
        .id             = 0,
        .num_resources  = 1,
        .resource       = &smbus_fpga_resource,
};

static struct resource smbus_pcie_resource = {
        .start          = 0x07fffc30,
        .end            = 0x07fffc30 + SZ_32 - 1,
        .flags          = IORESOURCE_MEM,
};

static struct platform_device smbus_pcie_device = {
        .name           = "i2c-sdk7786",
        .id             = 1,
        .num_resources  = 1,
        .resource       = &smbus_pcie_resource,
};

static struct i2c_board_info __initdata sdk7786_i2c_devices[] = {
        {
                I2C_BOARD_INFO("max6900", 0x68),
        },
};

static struct platform_device *sh7786_devices[] __initdata = {
        &heartbeat_device,
        &smsc911x_device,
        &smbus_fpga_device,
        &smbus_pcie_device,
};

static int sdk7786_i2c_setup(void)
{
        unsigned int tmp;

        /*
         * Hand over I2C control to the FPGA.
         */
        tmp = fpga_read_reg(SBCR);
        tmp &= ~SCBR_I2CCEN;
        tmp |= SCBR_I2CMEN;
        fpga_write_reg(tmp, SBCR);

        return i2c_register_board_info(0, sdk7786_i2c_devices,
                                       ARRAY_SIZE(sdk7786_i2c_devices));
}

static int __init sdk7786_devices_setup(void)
{
        int ret;

        ret = platform_add_devices(sh7786_devices, ARRAY_SIZE(sh7786_devices));
        if (unlikely(ret != 0))
                return ret;

        return sdk7786_i2c_setup();
}
device_initcall(sdk7786_devices_setup);

static int sdk7786_mode_pins(void)
{
        return fpga_read_reg(MODSWR);
}

/*
 * FPGA-driven PCIe clocks
 *
 * Historically these include the oscillator, clock B (slots 2/3/4) and
 * clock A (slot 1 and the CPU clock). Newer revs of the PCB shove
 * everything under a single PCIe clocks enable bit that happens to map
 * to the same bit position as the oscillator bit for earlier FPGA
 * versions.
 *
 * Given that the legacy clocks have the side-effect of shutting the CPU
 * off through the FPGA along with the PCI slots, we simply leave them in
 * their initial state and don't bother registering them with the clock
 * framework.
 */
static int sdk7786_pcie_clk_enable(struct clk *clk)
{
        fpga_write_reg(fpga_read_reg(PCIECR) | PCIECR_CLKEN, PCIECR);
        return 0;
}

static void sdk7786_pcie_clk_disable(struct clk *clk)
{
        fpga_write_reg(fpga_read_reg(PCIECR) & ~PCIECR_CLKEN, PCIECR);
}

static struct sh_clk_ops sdk7786_pcie_clk_ops = {
        .enable         = sdk7786_pcie_clk_enable,
        .disable        = sdk7786_pcie_clk_disable,
};

static struct clk sdk7786_pcie_clk = {
        .ops            = &sdk7786_pcie_clk_ops,
};

static struct clk_lookup sdk7786_pcie_cl = {
        .con_id         = "pcie_plat_clk",
        .clk            = &sdk7786_pcie_clk,
};

static int sdk7786_clk_init(void)
{
        struct clk *clk;
        int ret;

        /*
         * Only handle the EXTAL case, anyone interfacing a crystal
         * resonator will need to provide their own input clock.
         */
        if (test_mode_pin(MODE_PIN9))
                return -EINVAL;

        clk = clk_get(NULL, "extal");
        if (IS_ERR(clk))
                return PTR_ERR(clk);
        ret = clk_set_rate(clk, 33333333);
        clk_put(clk);

        /*
         * Setup the FPGA clocks.
         */
        ret = clk_register(&sdk7786_pcie_clk);
        if (unlikely(ret)) {
                pr_err("FPGA clock registration failed\n");
                return ret;
        }

        clkdev_add(&sdk7786_pcie_cl);

        return 0;
}

static void sdk7786_restart(char *cmd)
{
        fpga_write_reg(0xa5a5, SRSTR);
}

static void sdk7786_power_off(void)
{
        fpga_write_reg(fpga_read_reg(PWRCR) | PWRCR_PDWNREQ, PWRCR);

        /*
         * It can take up to 20us for the R8C to do its job, back off and
         * wait a bit until we've been shut off. Even though newer FPGA
         * versions don't set the ACK bit, the latency issue remains.
         */
        while ((fpga_read_reg(PWRCR) & PWRCR_PDWNACK) == 0)
                cpu_sleep();
}

/* Initialize the board */
static void __init sdk7786_setup(char **cmdline_p)
{
        pr_info("Renesas Technology Europe SDK7786 support:\n");

        regulator_register_fixed(0, dummy_supplies, ARRAY_SIZE(dummy_supplies));

        sdk7786_fpga_init();
        sdk7786_nmi_init();

        pr_info("\tPCB revision:\t%d\n", fpga_read_reg(PCBRR) & 0xf);

        machine_ops.restart = sdk7786_restart;
        pm_power_off = sdk7786_power_off;

        register_smp_ops(&shx3_smp_ops);
}

/*
 * The Machine Vector
 */
static struct sh_machine_vector mv_sdk7786 __initmv = {
        .mv_name                = "SDK7786",
        .mv_setup               = sdk7786_setup,
        .mv_mode_pins           = sdk7786_mode_pins,
        .mv_clk_init            = sdk7786_clk_init,
        .mv_init_irq            = sdk7786_init_irq,
};