/* $NetBSD: am3_platform.c,v 1.5 2025/09/06 21:02:41 thorpej Exp $ */

#include "opt_console.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: am3_platform.c,v 1.5 2025/09/06 21:02:41 thorpej Exp $");

#include <sys/param.h>

#include <dev/fdt/fdtvar.h>
#include <dev/fdt/fdt_platform.h>

#include <arm/fdt/arm_fdtvar.h>

#include <uvm/uvm_extern.h>

#include <dev/ic/comreg.h>

#include <machine/vmparam.h>
#include <arch/evbarm/fdt/platform.h>

extern struct bus_space armv7_generic_bs_tag;
extern struct arm32_bus_dma_tag arm_generic_dma_tag;

void am33xx_platform_early_putchar(char);

void __noasan
am33xx_platform_early_putchar(char c)
{
#ifdef CONSADDR
#define CONSADDR_VA ((CONSADDR - 0x44c00000) + (KERNEL_IO_VBASE | 0x04c00000))
        volatile uint32_t *uartaddr = cpu_earlydevice_va_p() ?
            (volatile uint32_t *)CONSADDR_VA :
            (volatile uint32_t *)CONSADDR;

        while ((le32toh(uartaddr[com_lsr]) & LSR_TXRDY) == 0)
                ;

        uartaddr[com_data] = htole32(c);
#endif
}


static const struct pmap_devmap *
am33xx_platform_devmap(void)
{
        static const struct pmap_devmap devmap[] = {
                DEVMAP_ENTRY(KERNEL_IO_VBASE | 0x04c00000, 0x44c00000, 0x00400000),
                DEVMAP_ENTRY(KERNEL_IO_VBASE | 0x08000000, 0x48000000, 0x01000000),
                DEVMAP_ENTRY(KERNEL_IO_VBASE | 0x0a000000, 0x4a000000, 0x01000000),
                DEVMAP_ENTRY_END
        };

        return devmap;
}

static void
am33xx_platform_init_attach_args(struct fdt_attach_args *faa)
{
        faa->faa_bst = &armv7_generic_bs_tag;
        faa->faa_dmat = &arm_generic_dma_tag;
}

static void
wdelay(bus_space_tag_t bst, bus_space_handle_t bsh)
{
        while (bus_space_read_4(bst, bsh, 0x34) != 0)
                delay(10);
}

static void
am33xx_platform_bootstrap(void)
{
        static bus_space_tag_t bst = &armv7_generic_bs_tag;
        static bus_space_handle_t bsh;

        bus_space_map(bst, 0x44e00000, 0x1000, 0, &bsh);
        bus_space_write_4(bst, bsh, 0x508, 0x1); /* CLKSEL_TIMER2_CLK: CLK_M_OSC */
        bus_space_write_4(bst, bsh, 0x50c, 0x1); /* CLKSEL_TIMER3_CLK: CLK_M_OSC */
        bus_space_write_4(bst, bsh, 0x80, 0x2); /* CM_PER_TIMER2_CLKCTRL: MODULEMODE: ENABLE */
        bus_space_write_4(bst, bsh, 0x84, 0x2); /* CM_PER_TIMER3_CLKCTRL: MODULEMODE: ENABLE */
        bus_space_unmap(bst, bsh, 0x1000);

        bus_space_map(bst, 0x48040000, 0x1000, 0, &bsh); /* TIMER2 for delay() */

        bus_space_write_4(bst, bsh, 0x40, 0); /* Load */
        bus_space_write_4(bst, bsh, 0x3c, 0); /* Counter */
        bus_space_write_4(bst, bsh, 0x38, 3); /* Control */

        bus_space_unmap(bst, bsh, 0x1000);

        bus_space_map(bst, 0x44e35000, 0x1000, 0, &bsh);
        wdelay(bst, bsh);
        bus_space_write_4(bst, bsh, 0x48, 0xAAAA);
        wdelay(bst, bsh);
        bus_space_write_4(bst, bsh, 0x48, 0x5555);
        wdelay(bst, bsh);
        bus_space_unmap(bst, bsh, 0x1000);

        bus_space_map(bst, 0x44e00000, 0x1000, 0, &bsh);
        bus_space_write_4(bst, bsh, 0x4d4, 0); /* suspend watch dog */
        bus_space_unmap(bst, bsh, 0x1000);
}

static u_int
am33xx_platform_uart_freq(void)
{
        return 48000000;
}

static void
am33xx_platform_delay(u_int n)
{
        static bus_space_tag_t bst = &armv7_generic_bs_tag;
        static bus_space_handle_t bsh = 0;

        uint32_t cur, prev;
        long ticks = n * 24;

        if (bsh == 0)
                bus_space_map(bst, 0x48040000, 0x1000, 0, &bsh); /* TIMER2 */

        prev = bus_space_read_4(bst, bsh, 0x3c);
        while (ticks > 0) {
                cur = bus_space_read_4(bst, bsh, 0x3c);
                if (cur >= prev)
                        ticks -= (cur - prev);
                else
                        ticks -= (UINT32_MAX - cur + prev);
                prev = cur;
        }
}

static void
am33xx_platform_reset(void)
{
        volatile uint32_t *resetaddr = (volatile uint32_t *)(KERNEL_IO_VBASE | 0x04e00f00);

        *resetaddr = 1;
}

static const struct fdt_platform am33xx_platform = {
        .fp_devmap = am33xx_platform_devmap,
        .fp_init_attach_args = am33xx_platform_init_attach_args,
        .fp_bootstrap = am33xx_platform_bootstrap,
        .fp_uart_freq = am33xx_platform_uart_freq,
        .fp_delay = am33xx_platform_delay,
        .fp_reset = am33xx_platform_reset,
};

FDT_PLATFORM(am33xx, "ti,am33xx", &am33xx_platform);