Updated formatting of gpt.c and boot.c.

fpga/zsbl/boot.c

@@ -34,6 +34,8 @@
 /*     return 0;; */
 /* } */
 
+#define SYSTEMCLOCK 20000000
+
 int disk_read(BYTE * buf, LBA_t sector, UINT count) {
   uint64_t r;
   UINT i;
@@ -46,25 +48,29 @@ int disk_read(BYTE * buf, LBA_t sector, UINT count) {
   crc = crc7(crc, sector & 0xff);
   crc = crc | 1;
   
-  if (sd_cmd(18, sector & 0xffffffff, crc) != 0x00) {
+  if ((r = sd_cmd(18, sector & 0xffffffff, crc) & 0xff) != 0x00) {
-    print_uart("disk_read: CMD18 failed. r = ");
+    print_uart("disk_read: CMD18 failed. r = 0x");
-    print_uart_byte(r & 0xff);
+    print_uart_byte(r);
     print_uart("\r\n");
     return -1;
   }
 
+  // write_reg(SPI_CSMODE, SIFIVE_SPI_CSMODE_MODE_HOLD);
   // Begin reading blocks
   for (i = 0; i < count; i++) {
     uint16_t crc, crc_exp;
     
     // Read the data token
     r = spi_readbyte();
-    if (r != SD_DATA_TOKEN) {
+    /* if (r != SD_DATA_TOKEN) { */
-      print_uart("Didn't receive data token first thing. Shoot: ");
+    /*   print_uart("Didn't receive data token first thing. Shoot: "); */
-      print_uart_byte(r & 0xff);
+    /*   print_uart_byte(r & 0xff); */
-      print_uart("\r\n");
+    /*   print_uart("\r\n"); */
-      return -1;
+    /*   return -1; */
-    }
+    /* } */
+
+    // Wait for data token
+    while((r & 0xff) != SD_DATA_TOKEN);
 
     // Read block into memory.
     for (int j = 0; j < 8; j++) {
@@ -77,7 +83,7 @@ int disk_read(BYTE * buf, LBA_t sector, UINT count) {
     crc_exp |= spi_txrx(0xff);
 
     if (crc != crc_exp) {
-      print_uart("Stinking CRC16 didn't match on block ");
+      print_uart("Stinking CRC16 didn't match on block read.\r\n");
       print_uart_int(i);
       print_uart("\r\n");
       return -1;
@@ -86,7 +92,8 @@ int disk_read(BYTE * buf, LBA_t sector, UINT count) {
   }
 
   sd_cmd(SD_CMD_STOP_TRANSMISSION, 0, 0x01);
-  spi_txrx(0xff);
+  // write_reg(SPI_CSMODE, SIFIVE_SPI_CSMODE_MODE_AUTO);
+  //spi_txrx(0xff);
   return 0;
 }
 
@@ -100,12 +107,17 @@ void copyFlash(QWORD address, QWORD * Dst, DWORD numBlocks) {
   // Initialize UART for messages
   init_uart(20000000, 115200);
 
-  print_uart("Booting wally.\r\n");
   // Print the wally banner
   print_uart(BANNER);
 
+  /* print_uart("System clock speed: "); */
+  /* print_uart_dec(SYSTEMCLOCK); */
+  /* print_uart("\r\n"); */
+
+  println_with_dec("Hello, does this work? Here's the clock: ", SYSTEMCLOCK);
+
   // Intialize the SD card
-  init_sd();
+  init_sd(SYSTEMCLOCK, SYSTEMCLOCK/2);
   
   ret = gpt_load_partitions();
 }

fpga/zsbl/gpt.c

@@ -3,18 +3,7 @@
 #include "uart.h"
 #include <stddef.h>
 
-/* PSUEDOCODE
-
-   Need to load GPT LBA 1 and read through the partition entries.
-   I need to find each of the relevant partition entries, possibly
-   by their partition names.
-   
-*/
-
 int gpt_load_partitions() {
-  // In this version of the GPT partition code
-  // I'm going to assume that the SD card is already initialized.
-
   // size_t block_size = 512/8;
   // long int lba1_buf[block_size];
 
@@ -22,15 +11,12 @@ int gpt_load_partitions() {
   
   int ret = 0;
   //ret = disk_read(/* BYTE * buf, LBA_t sector, UINT count, BYTE card_type */);
+  println("Getting GPT information.");
   ret = disk_read(lba1_buf, 1, 1);
 
-  /* Possible error handling with UART message
-  if ( ret != 0 ) {
-    
-  }*/
-
   gpt_pth_t *lba1 = (gpt_pth_t *)lba1_buf;
 
+  println("Getting partition entries.");
   BYTE lba2_buf[512];
   ret = disk_read(lba2_buf, (LBA_t)lba1->partition_entries_lba, 1);
 
@@ -40,6 +26,7 @@ int gpt_load_partitions() {
   partition_entries_t *kernel = (partition_entries_t *)(lba2_buf + 256);
 
   // Load device tree
+  println_with_int("Loading device tree at: 0x", FDT_ADDRESS);
   ret = disk_read((BYTE *)FDT_ADDRESS, fdt->first_lba, fdt->last_lba - fdt->first_lba + 1);
   if (ret < 0) {
     print_uart("Failed to load device tree!\r\n");
@@ -47,6 +34,7 @@ int gpt_load_partitions() {
   }
 
   // Load OpenSBI
+  println_with_int("Loading OpenSBI at: 0x", OPENSBI_ADDRESS);
   ret = disk_read((BYTE *)OPENSBI_ADDRESS, opensbi->first_lba, opensbi->last_lba - opensbi->first_lba + 1);
   if (ret < 0) {
     print_uart("Failed to load OpenSBI!\r\n");
@@ -54,6 +42,7 @@ int gpt_load_partitions() {
   }
 
   // Load Linux
+  println_with_int("Loading Linux Kernel at: 0x", KERNEL_ADDRESS);
   ret = disk_read((BYTE *)KERNEL_ADDRESS, kernel->first_lba,kernel->last_lba - kernel->first_lba + 1);
   if (ret < 0) {
     print_uart("Failed to load Linux!\r\n");

fpga/zsbl/uart.h

@@ -1,6 +1,7 @@
 #pragma once
 #include <stdint.h>
 
+// UART register addresses
 #define UART_BASE 0x10000000
 
 #define UART_RBR UART_BASE + 0x00
@@ -16,6 +17,7 @@
 #define UART_DLL UART_BASE + 0x00
 #define UART_DLM UART_BASE + 0x01
 
+// Primary function prototypes
 void init_uart(uint32_t freq, uint32_t baud);
 void write_reg_u8(uintptr_t addr, uint8_t value);
 uint8_t read_reg_u8(uintptr_t addr);
@@ -27,6 +29,7 @@ void print_uart_addr(uint64_t addr);
 void print_uart_hex(uint64_t addr, int n);
 void print_uart_byte(uint8_t byte);
 
+// Print numbers in hex with specified widths
 #define print_uart_int(addr) print_uart_hex(addr, 4)
 #define print_uart_addr(addr) print_uart_hex(addr, 8)
 #define print_uart_byte(addr) print_uart_hex(addr, 1)