Implement flashing from scratch rom

src/board/system76/galp3-c/acpi.c

@@ -30,6 +30,9 @@ uint8_t acpi_read(uint8_t addr) {
         ACPI_8 (0x14, peci_duty);
         ACPI_8 (0x15, peci_tcontrol);
         ACPI_8 (0x16, peci_tjmax);
+
+        // Set size of flash (from old firmware)
+        ACPI_8 (0xE5, 0x80);
     }
 
     DEBUG("acpi_read %02X = %02X\n", addr, data);

src/board/system76/galp3-c/pmc.c

@@ -1,5 +1,6 @@
 #include <board/acpi.h>
 #include <board/pmc.h>
+#include <board/scratch.h>
 #include <common/debug.h>
 
 void pmc_init(void) {
@@ -48,6 +49,12 @@ void pmc_event(struct Pmc * pmc) {
                 // TODO: queue is always empty
                 pmc_write(pmc, 0, PMC_TIMEOUT);
                 break;
+
+            case 0xDC:
+                DEBUG("  scratch rom\n");
+                pmc_write(pmc, 0x33, PMC_TIMEOUT);
+                scratch_trampoline();
+                break;
             }
         } else {
             DEBUG("pmc data: %02X\n", data);

src/board/system76/galp3-c/scratch.c

@@ -37,11 +37,18 @@ static void scratch_start(void) __naked {
 	__endasm;
 }
 
-// Enter scratch ROM
+// Enter or exit scratch ROM
-int scratch_trampoline(void) {
+void scratch_trampoline(void) {
 	// Uses SCAR1, 2, 3, and 4 which are mapped at 0x0800 in data space and are
     // 2048 bytes in size. SCAR0 cannot be used due to __pdata overwriting it.
 
+    if ((SCAR1H == 0x00) || (SCAR2H == 0x00) || (SCAR3H == 0x00) || (SCAR4H == 0x00)) {
+        // Disable scratch RAM mapping
+        SCAR1H = 0b11;
+        SCAR2H = 0b11;
+        SCAR3H = 0b11;
+        SCAR4H = 0b11;
+    } else {
         int i;
         // Copy scratch ROM
         for (i = 0; i < ARRAY_SIZE(scratch_rom) && i < ARRAY_SIZE(scratch_ram); i++) {
@@ -69,12 +76,10 @@ int scratch_trampoline(void) {
         SCAR4L = 0x00;
         SCAR4M = 0x08;
         SCAR4H = 0x00;
+    }
 
-    // Jump to scratch reset function
+    // Jump to reset function
     __asm__("ljmp 0");
-
-    // Should never happen
-    return 0;
 }
 
 // Finish segment located at 0x1000

src/board/system76/galp3-c/scratch/include/scratch/pmc.h

@@ -23,7 +23,7 @@ extern struct Pmc __code PMC_1;
 
 uint8_t pmc_status(struct Pmc * pmc);
 uint8_t pmc_read(struct Pmc * pmc);
-bool pmc_write(struct Pmc * pmc, uint8_t data, int timeout);
+bool pmc_write(struct Pmc * pmc, uint8_t data);
 
 volatile uint8_t __xdata __at(0x1500) PM1STS;
 volatile uint8_t __xdata __at(0x1501) PM1DO;

src/board/system76/galp3-c/scratch/main.c

@@ -1,5 +1,7 @@
 #include <stdbool.h>
 #include <stdint.h>
+#include <stdio.h>
+#define printf printf_small
 
 #include <scratch/pmc.h>
 
@@ -28,20 +30,73 @@ static int flash_transaction(uint32_t offset, uint8_t * data, int length, bool r
     return i;
 }
 
-#define PMC_TIMEOUT 1000
+enum PmcState {
+    PMC_STATE_DEFAULT,
+    PMC_STATE_WRITE,
+};
+
+static uint8_t __xdata __at(0x1F07) EWDKEYR;
 
 static void pmc_event(struct Pmc * pmc) {
+    static enum PmcState state = PMC_STATE_DEFAULT;
+
     uint8_t sts = pmc_status(pmc);
     if (sts & PMC_STS_IBF) {
         uint8_t data = pmc_read(pmc);
+        //printf("%x\n", data);
         if (sts & PMC_STS_CMD) {
-        } else {
+            switch (state) {
+                case PMC_STATE_DEFAULT:
+                    switch (data) {
+                        case 0x01:
+                            // Enable follow
+                            ECINDAR3 = 0x0F;
+                            break;
+                        case 0x02:
+                            // Generate high CE#
+                            data = 0;
+                            flash_transaction(0x7FFFFE00, &data, 1, false);
+                            // Fall through
+                        case 0x03:
+                            state = PMC_STATE_WRITE;
+                            break;
+                        case 0x04:
+                            // Read data
+                            flash_transaction(0x7FFFFD00, &data, 1, true);
+                            pmc_write(pmc, data);
+                            break;
+                        case 0x05:
+                            // Disable follow
+                            ECINDAR3 = 0x00;
+                            break;
+                        case 0xFC:
+                            // Clear processor caches
+                            __asm__("mov 0xf7, #1");
+                            __asm__("nop");
+                            __asm__("mov 0xf7, #1");
+                            __asm__("nop");
+                            __asm__("mov 0xf7, #1");
+                            __asm__("nop");
+                            __asm__("mov 0xf7, #1");
+                            __asm__("nop");
+                            // Exit scratch ROM by going through trampoline
+                            __asm__("ljmp 0x1000");
+                            break;
+                    }
+                    break;
+                case PMC_STATE_WRITE:
+                    // Write command or data
+                    flash_transaction(0x7FFFFD00, &data, 1, false);
+                    state = PMC_STATE_DEFAULT;
+                    break;
+            }
         }
     }
 }
 
 // Main program while running in scratch ROM
 void main(void) {
+    printf("scratch\n");
 	for (;;) {
         pmc_event(&PMC_1);
     }

src/board/system76/galp3-c/scratch/pmc.c

@@ -17,16 +17,8 @@ uint8_t pmc_read(struct Pmc * pmc) {
     return *(pmc->data_in);
 }
 
-static bool pmc_wait(struct Pmc * pmc, int timeout) {
+bool pmc_write(struct Pmc * pmc, uint8_t data) {
-    while (pmc_status(pmc) & PMC_STS_OBF) {
+    while (pmc_status(pmc) & PMC_STS_OBF) {}
-        if (timeout == 0) return false;
-        timeout -= 1;
-    }
-    return true;
-}
-
-bool pmc_write(struct Pmc * pmc, uint8_t data, int timeout) {
-    if (!pmc_wait(pmc, timeout)) return false;
     *(pmc->data_out) = data;
     return true;
 }

src/board/system76/galp3-c/scratch/stdio.c

@@ -0,0 +1,8 @@
+#include <mcs51/8051.h>
+#include <stdio.h>
+
+int putchar(int c) {
+    unsigned char byte = (unsigned char)c;
+    SBUF = byte;
+    return (int)byte;
+}

src/board/system76/galp3-c/stdio.c

@@ -1,9 +1,13 @@
 #include <stdio.h>
+#include <mcs51/8051.h>
 
-#include <common/i2c.h>
+#ifdef I2C_DEBUGGER
+    #include <common/i2c.h>
+#endif
 
 int putchar(int c) {
     unsigned char byte = (unsigned char)c;
+    SBUF = byte;
 #ifdef I2C_DEBUGGER
     i2c_send(I2C_DEBUGGER, &byte, 1);
 #endif