// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Buffalo Terastation Pro II/Live Board Setup
 *
 * Maintainer: Sylver Bruneau <sylver.bruneau@googlemail.com>
 */
#include <linux/gpio.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/mtd/physmap.h>
#include <linux/mv643xx_eth.h>
#include <linux/i2c.h>
#include <linux/serial_reg.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/pci.h>
#include "common.h"
#include "mpp.h"
#include "orion5x.h"

/*****************************************************************************
 * Terastation Pro 2/Live Info
 ****************************************************************************/

/*
 * Terastation Pro 2 hardware :
 * - Marvell 88F5281-D0
 * - Marvell 88SX6042 SATA controller (PCI)
 * - Marvell 88E1118 Gigabit Ethernet PHY
 * - 256KB NOR flash
 * - 128MB of DDR RAM
 * - PCIe port (not equipped)
 */

/*
 * 256K NOR flash Device bus boot chip select
 */

#define TSP2_NOR_BOOT_BASE      0xf4000000
#define TSP2_NOR_BOOT_SIZE      SZ_256K

/*****************************************************************************
 * 256KB NOR Flash on BOOT Device
 ****************************************************************************/

static struct physmap_flash_data tsp2_nor_flash_data = {
        .width    = 1,
};

static struct resource tsp2_nor_flash_resource = {
        .flags = IORESOURCE_MEM,
        .start = TSP2_NOR_BOOT_BASE,
        .end   = TSP2_NOR_BOOT_BASE + TSP2_NOR_BOOT_SIZE - 1,
};

static struct platform_device tsp2_nor_flash = {
        .name          = "physmap-flash",
        .id            = 0,
        .dev           = {
                .platform_data  = &tsp2_nor_flash_data,
        },
        .num_resources = 1,
        .resource      = &tsp2_nor_flash_resource,
};

/*****************************************************************************
 * PCI
 ****************************************************************************/
#define TSP2_PCI_SLOT0_OFFS             7
#define TSP2_PCI_SLOT0_IRQ_PIN          11

static void __init tsp2_pci_preinit(void)
{
        int pin;

        /*
         * Configure PCI GPIO IRQ pins
         */
        pin = TSP2_PCI_SLOT0_IRQ_PIN;
        if (gpio_request(pin, "PCI Int1") == 0) {
                if (gpio_direction_input(pin) == 0) {
                        irq_set_irq_type(gpio_to_irq(pin), IRQ_TYPE_LEVEL_LOW);
                } else {
                        printk(KERN_ERR "tsp2_pci_preinit failed "
                                        "to set_irq_type pin %d\n", pin);
                        gpio_free(pin);
                }
        } else {
                printk(KERN_ERR "tsp2_pci_preinit failed to "
                                "gpio_request %d\n", pin);
        }
}

static int __init tsp2_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
        int irq;

        /*
         * Check for devices with hard-wired IRQs.
         */
        irq = orion5x_pci_map_irq(dev, slot, pin);
        if (irq != -1)
                return irq;

        /*
         * PCI IRQs are connected via GPIOs.
         */
        if (slot == TSP2_PCI_SLOT0_OFFS)
                return gpio_to_irq(TSP2_PCI_SLOT0_IRQ_PIN);

        return -1;
}

static struct hw_pci tsp2_pci __initdata = {
        .nr_controllers = 2,
        .preinit        = tsp2_pci_preinit,
        .setup          = orion5x_pci_sys_setup,
        .scan           = orion5x_pci_sys_scan_bus,
        .map_irq        = tsp2_pci_map_irq,
};

static int __init tsp2_pci_init(void)
{
        if (machine_is_terastation_pro2())
                pci_common_init(&tsp2_pci);

        return 0;
}

subsys_initcall(tsp2_pci_init);

/*****************************************************************************
 * Ethernet
 ****************************************************************************/

static struct mv643xx_eth_platform_data tsp2_eth_data = {
        .phy_addr       = 0,
};

/*****************************************************************************
 * RTC 5C372a on I2C bus
 ****************************************************************************/

#define TSP2_RTC_GPIO   9

static struct i2c_board_info __initdata tsp2_i2c_rtc = {
        I2C_BOARD_INFO("rs5c372a", 0x32),
};

/*****************************************************************************
 * Terastation Pro II specific power off method via UART1-attached
 * microcontroller
 ****************************************************************************/

#define UART1_REG(x)    (UART1_VIRT_BASE + ((UART_##x) << 2))

static int tsp2_miconread(unsigned char *buf, int count)
{
        int i;
        int timeout;

        for (i = 0; i < count; i++) {
                timeout = 10;

                while (!(readl(UART1_REG(LSR)) & UART_LSR_DR)) {
                        if (--timeout == 0)
                                break;
                        udelay(1000);
                }

                if (timeout == 0)
                        break;
                buf[i] = readl(UART1_REG(RX));
        }

        /* return read bytes */
        return i;
}

static int tsp2_miconwrite(const unsigned char *buf, int count)
{
        int i = 0;

        while (count--) {
                while (!(readl(UART1_REG(LSR)) & UART_LSR_THRE))
                        barrier();
                writel(buf[i++], UART1_REG(TX));
        }

        return 0;
}

static int tsp2_miconsend(const unsigned char *data, int count)
{
        int i;
        unsigned char checksum = 0;
        unsigned char recv_buf[40];
        unsigned char send_buf[40];
        unsigned char correct_ack[3];
        int retry = 2;

        /* Generate checksum */
        for (i = 0; i < count; i++)
                checksum -=  data[i];

        do {
                /* Send data */
                tsp2_miconwrite(data, count);

                /* send checksum */
                tsp2_miconwrite(&checksum, 1);

                if (tsp2_miconread(recv_buf, sizeof(recv_buf)) <= 3) {
                        printk(KERN_ERR ">%s: receive failed.\n", __func__);

                        /* send preamble to clear the receive buffer */
                        memset(&send_buf, 0xff, sizeof(send_buf));
                        tsp2_miconwrite(send_buf, sizeof(send_buf));

                        /* make dummy reads */
                        mdelay(100);
                        tsp2_miconread(recv_buf, sizeof(recv_buf));
                } else {
                        /* Generate expected ack */
                        correct_ack[0] = 0x01;
                        correct_ack[1] = data[1];
                        correct_ack[2] = 0x00;

                        /* checksum Check */
                        if ((recv_buf[0] + recv_buf[1] + recv_buf[2] +
                             recv_buf[3]) & 0xFF) {
                                printk(KERN_ERR ">%s: Checksum Error : "
                                        "Received data[%02x, %02x, %02x, %02x]"
                                        "\n", __func__, recv_buf[0],
                                        recv_buf[1], recv_buf[2], recv_buf[3]);
                        } else {
                                /* Check Received Data */
                                if (correct_ack[0] == recv_buf[0] &&
                                    correct_ack[1] == recv_buf[1] &&
                                    correct_ack[2] == recv_buf[2]) {
                                        /* Interval for next command */
                                        mdelay(10);

                                        /* Receive ACK */
                                        return 0;
                                }
                        }
                        /* Received NAK or illegal Data */
                        printk(KERN_ERR ">%s: Error : NAK or Illegal Data "
                                        "Received\n", __func__);
                }
        } while (retry--);

        /* Interval for next command */
        mdelay(10);

        return -1;
}

static void tsp2_power_off(void)
{
        const unsigned char watchdogkill[]      = {0x01, 0x35, 0x00};
        const unsigned char shutdownwait[]      = {0x00, 0x0c};
        const unsigned char poweroff[]          = {0x00, 0x06};
        /* 38400 baud divisor */
        const unsigned divisor = ((orion5x_tclk + (8 * 38400)) / (16 * 38400));

        pr_info("%s: triggering power-off...\n", __func__);

        /* hijack uart1 and reset into sane state (38400,8n1,even parity) */
        writel(0x83, UART1_REG(LCR));
        writel(divisor & 0xff, UART1_REG(DLL));
        writel((divisor >> 8) & 0xff, UART1_REG(DLM));
        writel(0x1b, UART1_REG(LCR));
        writel(0x00, UART1_REG(IER));
        writel(0x07, UART1_REG(FCR));
        writel(0x00, UART1_REG(MCR));

        /* Send the commands to shutdown the Terastation Pro II */
        tsp2_miconsend(watchdogkill, sizeof(watchdogkill)) ;
        tsp2_miconsend(shutdownwait, sizeof(shutdownwait)) ;
        tsp2_miconsend(poweroff, sizeof(poweroff));
}

/*****************************************************************************
 * General Setup
 ****************************************************************************/
static unsigned int tsp2_mpp_modes[] __initdata = {
        MPP0_PCIE_RST_OUTn,
        MPP1_UNUSED,
        MPP2_UNUSED,
        MPP3_UNUSED,
        MPP4_NAND,              /* BOOT NAND Flash REn */
        MPP5_NAND,              /* BOOT NAND Flash WEn */
        MPP6_NAND,              /* BOOT NAND Flash HREn[0] */
        MPP7_NAND,              /* BOOT NAND Flash WEn[0] */
        MPP8_GPIO,              /* MICON int */
        MPP9_GPIO,              /* RTC int */
        MPP10_UNUSED,
        MPP11_GPIO,             /* PCI Int A */
        MPP12_UNUSED,
        MPP13_GPIO,             /* UPS on UART0 enable */
        MPP14_GPIO,             /* UPS low battery detection */
        MPP15_UNUSED,
        MPP16_UART,             /* UART1 RXD */
        MPP17_UART,             /* UART1 TXD */
        MPP18_UART,             /* UART1 CTSn */
        MPP19_UART,             /* UART1 RTSn */
        0,
};

static void __init tsp2_init(void)
{
        /*
         * Setup basic Orion functions. Need to be called early.
         */
        orion5x_init();

        orion5x_mpp_conf(tsp2_mpp_modes);

        /*
         * Configure peripherals.
         */
        mvebu_mbus_add_window_by_id(ORION_MBUS_DEVBUS_BOOT_TARGET,
                                    ORION_MBUS_DEVBUS_BOOT_ATTR,
                                    TSP2_NOR_BOOT_BASE,
                                    TSP2_NOR_BOOT_SIZE);
        platform_device_register(&tsp2_nor_flash);

        orion5x_ehci0_init();
        orion5x_eth_init(&tsp2_eth_data);
        orion5x_i2c_init();
        orion5x_uart0_init();
        orion5x_uart1_init();

        /* Get RTC IRQ and register the chip */
        if (gpio_request(TSP2_RTC_GPIO, "rtc") == 0) {
                if (gpio_direction_input(TSP2_RTC_GPIO) == 0)
                        tsp2_i2c_rtc.irq = gpio_to_irq(TSP2_RTC_GPIO);
                else
                        gpio_free(TSP2_RTC_GPIO);
        }
        if (tsp2_i2c_rtc.irq == 0)
                pr_warn("tsp2_init: failed to get RTC IRQ\n");
        i2c_register_board_info(0, &tsp2_i2c_rtc, 1);

        /* register Terastation Pro II specific power-off method */
        register_platform_power_off(tsp2_power_off);
}

MACHINE_START(TERASTATION_PRO2, "Buffalo Terastation Pro II/Live")
        /* Maintainer:  Sylver Bruneau <sylver.bruneau@googlemail.com> */
        .atag_offset    = 0x100,
        .nr_irqs        = ORION5X_NR_IRQS,
        .init_machine   = tsp2_init,
        .map_io         = orion5x_map_io,
        .init_early     = orion5x_init_early,
        .init_irq       = orion5x_init_irq,
        .init_time      = orion5x_timer_init,
        .fixup          = tag_fixup_mem32,
        .restart        = orion5x_restart,
MACHINE_END