boot: make bootloader multitarget

sw/bootloader/Makefile

@@ -1,19 +1,41 @@
-EXEC:= bootloader.elf
+EXEC:= bootloader
 
-CFLAGS:= -mabi=ilp32 -march=rv32i -nostartfiles -ffreestanding -DTARGET_HYDROGENSOC -Os
+RVPREFIX:= riscv64-unknown-elf
+
+CFLAGS:= -mabi=ilp32 -march=rv32i -nostartfiles -ffreestanding -Os
 CFLAGS+= -I $(RVATOM_LIB)/include
-LFLAGS:= -L $(RVATOM_LIB)/ -T $(RVATOM_LIB)/link/link_boot_hydrogensoc.ld -lcatom -Xlinker -Map $(EXEC).map -Wl,--gc-sections
+LFLAGS:= -L $(RVATOM_LIB)/ -T $(RVATOM_LIB)/link/link_bootloader.ld -lcatom -Xlinker -Map $(EXEC).map -Wl,--gc-sections
+
+CONVELF_ARGS:= -t elf -c
+
+ifeq ($(MAKECMDGOALS),clean)
+else
+    ifeq ($(soctarget), atombones)
+        CFLAGS += -DTARGET_ATOMBONES -DTARGET_HEADER='"atombones.h"'
+    else
+    ifeq ($(soctarget), hydrogensoc)
+        CFLAGS += -DTARGET_HYDROGENSOC -DTARGET_HEADER='"hydrogensoc.h"'
+    else
+       $(error Invalid SoC target: $(soctarget))
+    endif
+	endif
+endif
+
+
+default: $(EXEC).elf $(EXEC).objdump $(EXEC).bin $(EXEC).hex
+
+$(EXEC).elf: main.c crt0.S
+	$(RVPREFIX)-gcc $(CFLAGS) -o $@ $^ $(LFLAGS)
 
-default: boot
+$(EXEC).objdump: $(EXEC).elf
+	$(RVPREFIX)-objdump -htd $< > $@
 
-.PHONY: boot
-boot: $(EXEC)
+$(EXEC).bin: $(EXEC).elf
+	$(RVPREFIX)-objcopy -O binary $< $@
 
-$(EXEC): main.c crt0.S
-	riscv64-unknown-elf-gcc $(CFLAGS) -o $@ $^ $(LFLAGS)
-	riscv64-unknown-elf-objdump -htd $@ > $@.objdump
-	python3 $$RVATOM/scripts/convelf.py -t elf -j hydrogensoc.json --keep-temp $(EXEC) -c
+$(EXEC).hex: $(EXEC).elf
+	convelf.py $(CONVELF_ARGS) -m="BOOTROM:0x00010000:8192:h:$@" $<
 
 .PHONY: clean
 clean:
-	rm -f *.o *.objdump *.map *.elf *.hex
+	rm -f *.o *.objdump *.map *.elf *.hex *.bin

sw/bootloader/atombones.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stdint.h>
+
+extern uint32_t __approm_start;
+
+/**
+ * @brief Platform specific initialization
+ * 
+ * @return void* address to jump to after boot
+ */
+void * platform_init() {
+    // Jump to start of approm
+    return (void *) &__approm_start;
+}

sw/bootloader/flashboot.h

@@ -0,0 +1,58 @@
+#pragma once
+
+#include <stdint.h>
+#include <spi.h>
+
+// Flash definitions
+#define FLASH_CMD_READ 0x03
+#define SPI_REG_SCKDIV_OFFSET   0x00
+#define SPI_REG_SCTRL_OFFSET    0x04
+#define SPI_REG_TDATA_OFFSET    0x08
+#define SPI_REG_RDATA_OFFSET    0x0c
+#define SPI_REG_CSCTRL_OFFSET   0x10
+#define SPI_REG_DCTRL_OFFSET    0x14
+
+/**
+ * @brief Copies Data from FLAST to dest
+ * 
+ * @param dest dest buffer
+ * @param src_addr source address in flash
+ * @param len 
+ * @return int 
+ */
+int flashcpy(uint8_t *dest, uint32_t src_addr, uint32_t len) {
+    struct SPI_Config cfg = {
+        .base_addr = SPI_ADDR,
+        .enable = true,
+        .pha = false,
+        .pol = false,
+        .lsb_first = false,
+        .baudrate = 1000000,
+        .device_num = 0,
+        .cs_mode = CSMODE_DISABLE,
+        .post_cs_low_delay = 1,
+        .pre_cs_high_delay = 1,
+        .loopback_enable=false
+    };
+    spi_init(&cfg);
+
+    // select
+    REG32(cfg.base_addr, SPI_REG_CSCTRL_OFFSET) = bitset(REG32(cfg.base_addr, SPI_REG_CSCTRL_OFFSET), 24+cfg.device_num);
+    spi_transfer(&cfg, FLASH_CMD_READ);
+    spi_transfer(&cfg, src_addr >> 16);
+	spi_transfer(&cfg, src_addr >> 8);
+	spi_transfer(&cfg, src_addr);
+
+    while(len--) {
+        REG8(cfg.base_addr, SPI_REG_TDATA_OFFSET) = 0x0;
+        while(REG32(SPI_ADDR, SPI_REG_SCTRL_OFFSET) >> 31)
+            asm volatile("");
+        *(dest++) = REG8(cfg.base_addr, SPI_REG_RDATA_OFFSET);
+    }
+
+    // deselect
+    REG32(cfg.base_addr, SPI_REG_CSCTRL_OFFSET) = bitclear(REG32(cfg.base_addr, SPI_REG_CSCTRL_OFFSET), 24+cfg.device_num);
+    cfg.cs_mode = CSMODE_AUTO;
+    spi_init(&cfg);
+    return 0;
+}

sw/bootloader/hydrogensoc.h

@@ -0,0 +1,97 @@
+#pragma once
+
+#include "gpio.h"
+#include "time.h"
+#include "mmio.h"
+#include "spi.h"
+
+#include "flashboot.h"
+
+#define STRINGIFY(s) #s
+#define EXPAND_AND_STRINGIFY(s) STRINGIFY(s)
+
+extern uint32_t __approm_start;
+extern uint32_t __approm_size;
+
+
+//-------------------- Configuration --------------------
+#define BOOTLED_PIN 0
+#define BOOTMODE_PIN0 8
+#define BOOTMODE_PIN1 9
+
+// Address offset at which image resides
+#define FLASH_IMG_OFFSET    0x000c0000
+
+// Size of Image
+#define FLASH_IMG_SIZE      32 * 1024       // 32 KB
+
+// number of flashes to indicate entering of bootloader
+#define START_LED_FLASHES   3
+
+// number of flashes to indicate entering of user application
+#define END_LED_FLASHES   1
+//-------------------------------------------------------
+
+
+/**
+ * @brief Blink BOOTLED
+ * 
+ * @param pin led pin
+ * @param count number of times to blink
+ * @param time_period time_period in of one ON & OFF
+ */
+void led_blink(int pin, int count, int time_period)
+{
+    for(int i=0; i<count; i++) 
+    {
+        gpio_write(pin, HIGH);
+        sleep_ms(time_period >> 1);
+        gpio_write(pin, LOW);
+        sleep_ms(time_period >> 1);
+    }
+}
+
+
+/**
+ * @brief Platform specific initialization
+ * 
+ * @return void* address to jump to after boot
+ */
+void * platform_init() {
+    // Initialize GPIO
+    gpio_setmode(BOOTLED_PIN, OUTPUT);     
+    gpio_setmode(BOOTMODE_PIN0, INPUT);
+    gpio_setmode(BOOTMODE_PIN1, INPUT);
+
+    // Blink LED START_LED_FLASHES times (signal entering of bootloader)
+    led_blink(BOOTLED_PIN, START_LED_FLASHES, 50);
+
+    // get bootmode
+    uint8_t bootmode = (uint8_t)gpio_read(BOOTMODE_PIN0)
+                        | (((uint8_t)gpio_read(BOOTMODE_PIN1)) << 1);
+    /**
+     * Bootmode: 
+     *  0b00: flashboot
+     *  0b01: jump to ram
+     *  default: infinite loop
+    */
+    if (bootmode == 0b00) {
+        // Bootmode: flash boot
+        P(puts("flashboot: Copying from " EXPAND_AND_STRINGIFY(FLASH_IMG_OFFSET) "\n");)
+        // copy from flash
+        flashcpy((uint8_t *)&__approm_start, FLASH_IMG_OFFSET, FLASH_IMG_SIZE);
+    } else if (bootmode == 0b01) {
+        // Bootmode: jump to ram
+    } else { 
+        // Bootmode: Infinite loop
+        while(1){
+            asm volatile("");
+        }
+    }
+
+    // Blink single (signal jump to user code)
+    led_blink(BOOTLED_PIN, END_LED_FLASHES, 50);
+
+    // Jump to start of approm
+    return (void *) &__approm_start;
+}