--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nintendo 64 init.
+ *
+ * Copyright (C) 2021 Lauri Kasanen
+ */
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/memblock.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/simplefb.h>
+#include <linux/string.h>
+
+#include <asm/bootinfo.h>
+#include <asm/fw/fw.h>
+#include <asm/time.h>
+
+#define IO_MEM_RESOURCE_START 0UL
+#define IO_MEM_RESOURCE_END 0x1fffffffUL
+
+/*
+ * System-specifc irq names for clarity
+ */
+#define MIPS_CPU_IRQ(x) (MIPS_CPU_IRQ_BASE + (x))
+#define MIPS_SOFTINT0_IRQ MIPS_CPU_IRQ(0)
+#define MIPS_SOFTINT1_IRQ MIPS_CPU_IRQ(1)
+#define RCP_IRQ MIPS_CPU_IRQ(2)
+#define CART_IRQ MIPS_CPU_IRQ(3)
+#define PRENMI_IRQ MIPS_CPU_IRQ(4)
+#define RDBR_IRQ MIPS_CPU_IRQ(5)
+#define RDBW_IRQ MIPS_CPU_IRQ(6)
+#define TIMER_IRQ MIPS_CPU_IRQ(7)
+
+static void __init iomem_resource_init(void)
+{
+ iomem_resource.start = IO_MEM_RESOURCE_START;
+ iomem_resource.end = IO_MEM_RESOURCE_END;
+}
+
+const char *get_system_type(void)
+{
+ return "Nintendo 64";
+}
+
+void __init prom_init(void)
+{
+ fw_init_cmdline();
+}
+
+#define W 320
+#define H 240
+#define REG_BASE ((u32 *) CKSEG1ADDR(0x4400000))
+
+static void __init n64rdp_write_reg(const u8 reg, const u32 value)
+{
+ __raw_writel(value, REG_BASE + reg);
+}
+
+#undef REG_BASE
+
+static const u32 ntsc_320[] __initconst = {
+ 0x00013212, 0x00000000, 0x00000140, 0x00000200,
+ 0x00000000, 0x03e52239, 0x0000020d, 0x00000c15,
+ 0x0c150c15, 0x006c02ec, 0x002501ff, 0x000e0204,
+ 0x00000200, 0x00000400
+};
+
+#define MI_REG_BASE 0x4300000
+#define NUM_MI_REGS 4
+#define AI_REG_BASE 0x4500000
+#define NUM_AI_REGS 6
+#define PI_REG_BASE 0x4600000
+#define NUM_PI_REGS 5
+#define SI_REG_BASE 0x4800000
+#define NUM_SI_REGS 7
+
+static int __init n64_platform_init(void)
+{
+ static const char simplefb_resname[] = "FB";
+ static const struct simplefb_platform_data mode = {
+ .width = W,
+ .height = H,
+ .stride = W * 2,
+ .format = "r5g5b5a1"
+ };
+ struct resource res[3];
+ void *orig;
+ unsigned long phys;
+ unsigned i;
+
+ memset(res, 0, sizeof(struct resource) * 3);
+ res[0].flags = IORESOURCE_MEM;
+ res[0].start = MI_REG_BASE;
+ res[0].end = MI_REG_BASE + NUM_MI_REGS * 4 - 1;
+
+ res[1].flags = IORESOURCE_MEM;
+ res[1].start = AI_REG_BASE;
+ res[1].end = AI_REG_BASE + NUM_AI_REGS * 4 - 1;
+
+ res[2].flags = IORESOURCE_IRQ;
+ res[2].start = RCP_IRQ;
+ res[2].end = RCP_IRQ;
+
+ platform_device_register_simple("n64audio", -1, res, 3);
+
+ memset(&res[0], 0, sizeof(res[0]));
+ res[0].flags = IORESOURCE_MEM;
+ res[0].start = PI_REG_BASE;
+ res[0].end = PI_REG_BASE + NUM_PI_REGS * 4 - 1;
+
+ platform_device_register_simple("n64cart", -1, res, 1);
+
+ memset(&res[0], 0, sizeof(res[0]));
+ res[0].flags = IORESOURCE_MEM;
+ res[0].start = SI_REG_BASE;
+ res[0].end = SI_REG_BASE + NUM_SI_REGS * 4 - 1;
+
+ platform_device_register_simple("n64joy", -1, res, 1);
+
+ /* The framebuffer needs 64-byte alignment */
+ orig = kzalloc(W * H * 2 + 63, GFP_DMA | GFP_KERNEL);
+ if (!orig)
+ return -ENOMEM;
+ phys = virt_to_phys(orig);
+ phys += 63;
+ phys &= ~63;
+
+ for (i = 0; i < ARRAY_SIZE(ntsc_320); i++) {
+ if (i == 1)
+ n64rdp_write_reg(i, phys);
+ else
+ n64rdp_write_reg(i, ntsc_320[i]);
+ }
+
+ /* setup IORESOURCE_MEM as framebuffer memory */
+ memset(&res[0], 0, sizeof(res[0]));
+ res[0].flags = IORESOURCE_MEM;
+ res[0].name = simplefb_resname;
+ res[0].start = phys;
+ res[0].end = phys + W * H * 2 - 1;
+
+ platform_device_register_resndata(NULL, "simple-framebuffer", 0,
+ &res[0], 1, &mode, sizeof(mode));
+
+ return 0;
+}
+
+#undef W
+#undef H
+
+arch_initcall(n64_platform_init);
+
+void __init plat_mem_setup(void)
+{
+ iomem_resource_init();
+ memblock_add(0x0, 8 * 1024 * 1024); /* Bootloader blocks the 4mb config */
+}
+
+void __init plat_time_init(void)
+{
+ /* 93.75 MHz cpu, count register runs at half rate */
+ mips_hpt_frequency = 93750000 / 2;
+}