diff --git a/fpga/zsbl/Makefile b/fpga/zsbl/Makefile
index bd30033fc..37323b813 100644
--- a/fpga/zsbl/Makefile
+++ b/fpga/zsbl/Makefile
@@ -16,7 +16,7 @@ OBJECTS		:= $(OBJECTS:.$(CPPEXT)=.$(OBJEXT))
 OBJECTS		:= $(patsubst $(SRCDIR)/%,$(BUILDDIR)/%,$(OBJECTS))
 
 TARGETDIR	:= bin
-TARGET		:= $(TARGETDIR)/fpga-test-sdc
+TARGET		:= $(TARGETDIR)/boot
 ROOT		:= ..
 LIBRARY_DIRS	:= 
 LIBRARY_FILES	:=
@@ -24,11 +24,13 @@ LIBRARY_FILES	:=
 MARCH           :=-march=rv64imfdc_zifencei
 MABI            :=-mabi=lp64d
 LINK_FLAGS      :=$(MARCH) $(MABI) -nostartfiles
-LINKER		:=linker.x
+LINKER		:=linker1000.x
 
 
 AFLAGS =$(MARCH) $(MABI) -W
-CFLAGS =$(MARCH) $(MABI) -mcmodel=medany  -O2
+# Override directive allows us to prepend other options on the command line
+# e.g. $ make CFLAGS=-g
+override CFLAGS +=$(MARCH) $(MABI) -mcmodel=medany -O2 -g
 AS=riscv64-unknown-elf-as
 CC=riscv64-unknown-elf-gcc
 AR=riscv64-unknown-elf-ar
@@ -104,7 +106,7 @@ $(BUILDDIR)/%.$(OBJEXT): $(SRCDIR)/%.$(CPPEXT)
 # convert to hex
 $(TARGET).memfile: $(TARGET)
 	@echo 'Making object dump file.'
-	@riscv64-unknown-elf-objdump -D $< > $<.objdump
+	riscv64-unknown-elf-objdump -DS $< > $<.objdump
 	@echo 'Making memory file'
 	riscv64-unknown-elf-elf2hex --bit-width 64 --input $^ --output $@
 	extractFunctionRadix.sh $<.objdump
diff --git a/fpga/zsbl/bios.s b/fpga/zsbl/bios.s
index 7954eab7a..9a5d6e21f 100644
--- a/fpga/zsbl/bios.s
+++ b/fpga/zsbl/bios.s
@@ -49,7 +49,12 @@ _start:
 	# set the stack pointer to the top of memory - 8 bytes (pointer size)
 	li sp, 0x87FFFFF8
 
-	jal ra, main
+	li a0, 0x00000000
+	li a1, 0x80000000
+	#li a2, 128*1024*1024/512 # copy 128MB
+	li a2, 127*1024*1024/512 # copy 127MB upper 1MB contains the return address (ra)
+	#li a2, 800 # copy 400KB
+	jal ra, copyFlash
 	
 	fence.i
 	# now toggle led so we know the copy completed.
@@ -81,18 +86,16 @@ delay2:
 	# now that the card is copied and the led toggled we
 	# jump to the copied contents of the sd card.
 
-jumpToLinux:
-	csrr a0, mhartid
-        li s0, 0x80000000
-        la a1, _dtb
-        jr s0
+jumpToLinux:	
+	csrrs	a0, 0xF14, x0   # copy hart ID to a0
+	li	a1, 0x87000000  # end of memory? not 100% sure on this but it's 112MB
+	la	a2, end_of_bios
+	li	t0, 0x80000000  # start of code
+	
+	jalr	x0, t0, 0
+
 end_of_bios:	
 
+	
 
 
-.section .rodata
-.globl _dtb
-.align 4, 0
-_dtb:
-#.incbin "wally-vcu118.dtb"
-
diff --git a/fpga/zsbl/boot.c b/fpga/zsbl/boot.c
new file mode 100644
index 000000000..6e4780f55
--- /dev/null
+++ b/fpga/zsbl/boot.c
@@ -0,0 +1,422 @@
+#include <stddef.h>
+#include "boot.h"
+#include "gpt.h"
+
+/* Card type flags (card_type) */
+#define CT_MMC          0x01            /* MMC ver 3 */
+#define CT_SD1          0x02            /* SD ver 1 */
+#define CT_SD2          0x04            /* SD ver 2 */
+#define CT_SDC          (CT_SD1|CT_SD2) /* SD */
+#define CT_BLOCK        0x08            /* Block addressing */
+
+#define CMD0    (0)             /* GO_IDLE_STATE */
+#define CMD1    (1)             /* SEND_OP_COND */
+#define CMD2    (2)             /* SEND_CID */
+#define CMD3    (3)             /* RELATIVE_ADDR */
+#define CMD4    (4)
+#define CMD5    (5)             /* SLEEP_WAKE (SDC) */
+#define CMD6    (6)             /* SWITCH_FUNC */
+#define CMD7    (7)             /* SELECT */
+#define CMD8    (8)             /* SEND_IF_COND */
+#define CMD9    (9)             /* SEND_CSD */
+#define CMD10   (10)            /* SEND_CID */
+#define CMD11   (11)
+#define CMD12   (12)            /* STOP_TRANSMISSION */
+#define CMD13   (13)
+#define CMD15   (15)
+#define CMD16   (16)            /* SET_BLOCKLEN */
+#define CMD17   (17)            /* READ_SINGLE_BLOCK */
+#define CMD18   (18)            /* READ_MULTIPLE_BLOCK */
+#define CMD19   (19)
+#define CMD20   (20)
+#define CMD23   (23)
+#define CMD24   (24)
+#define CMD25   (25)
+#define CMD27   (27)
+#define CMD28   (28)
+#define CMD29   (29)
+#define CMD30   (30)
+#define CMD32   (32)
+#define CMD33   (33)
+#define CMD38   (38)
+#define CMD42   (42)
+#define CMD55   (55)            /* APP_CMD */
+#define CMD56   (56)
+#define ACMD6   (0x80+6)        /* define the data bus width */
+#define ACMD41  (0x80+41)       /* SEND_OP_COND (ACMD) */
+
+// Capability bits
+#define SDC_CAPABILITY_SD_4BIT  0x0001
+#define SDC_CAPABILITY_SD_RESET 0x0002
+#define SDC_CAPABILITY_ADDR     0xff00
+
+// Control bits
+#define SDC_CONTROL_SD_4BIT     0x0001
+#define SDC_CONTROL_SD_RESET    0x0002
+
+// Card detect bits
+#define SDC_CARD_INSERT_INT_EN  0x0001
+#define SDC_CARD_INSERT_INT_REQ 0x0002
+#define SDC_CARD_REMOVE_INT_EN  0x0004
+#define SDC_CARD_REMOVE_INT_REQ 0x0008
+
+// Command status bits
+#define SDC_CMD_INT_STATUS_CC   0x0001  // Command complete
+#define SDC_CMD_INT_STATUS_EI   0x0002  // Any error
+#define SDC_CMD_INT_STATUS_CTE  0x0004  // Timeout
+#define SDC_CMD_INT_STATUS_CCRC 0x0008  // CRC error
+#define SDC_CMD_INT_STATUS_CIE  0x0010  // Command code check error
+
+// Data status bits
+#define SDC_DAT_INT_STATUS_TRS  0x0001  // Transfer complete
+#define SDC_DAT_INT_STATUS_ERR  0x0002  // Any error
+#define SDC_DAT_INT_STATUS_CTE  0x0004  // Timeout
+#define SDC_DAT_INT_STATUS_CRC  0x0008  // CRC error
+#define SDC_DAT_INT_STATUS_CFE  0x0010  // Data FIFO underrun or overrun
+
+
+#define ERR_EOF             30
+#define ERR_NOT_ELF         31
+#define ERR_ELF_BITS        32
+#define ERR_ELF_ENDIANNESS  33
+#define ERR_CMD_CRC         34
+#define ERR_CMD_CHECK       35
+#define ERR_DATA_CRC        36
+#define ERR_DATA_FIFO       37
+#define ERR_BUF_ALIGNMENT   38
+#define FR_DISK_ERR         39
+#define FR_TIMEOUT          40
+
+struct sdc_regs {
+    volatile uint32_t argument;
+    volatile uint32_t command;
+    volatile uint32_t response1;
+    volatile uint32_t response2;
+    volatile uint32_t response3;
+    volatile uint32_t response4;
+    volatile uint32_t data_timeout;
+    volatile uint32_t control;
+    volatile uint32_t cmd_timeout;
+    volatile uint32_t clock_divider;
+    volatile uint32_t software_reset;
+    volatile uint32_t power_control;
+    volatile uint32_t capability;
+    volatile uint32_t cmd_int_status;
+    volatile uint32_t cmd_int_enable;
+    volatile uint32_t dat_int_status;
+    volatile uint32_t dat_int_enable;
+    volatile uint32_t block_size;
+    volatile uint32_t block_count;
+    volatile uint32_t card_detect;
+    volatile uint32_t res_50;
+    volatile uint32_t res_54;
+    volatile uint32_t res_58;
+    volatile uint32_t res_5c;
+    volatile uint64_t dma_addres;
+};
+
+#define MAX_BLOCK_CNT 0x1000
+
+#define SDC 0x00013000;
+
+// static struct sdc_regs * const regs __attribute__((section(".rodata"))) = (struct sdc_regs *)0x00013000;
+
+// static int errno __attribute__((section(".bss")));
+// static DSTATUS drv_status __attribute__((section(".bss")));
+// static BYTE card_type __attribute__((section(".bss")));
+// static uint32_t response[4] __attribute__((section(".bss")));
+// static int alt_mem __attribute__((section(".bss")));
+
+/*static const char * errno_to_str(void) {
+    switch (errno) {
+    case ERR_EOF: return "Unexpected EOF";
+    case ERR_NOT_ELF: return "Not an ELF file";
+    case ERR_ELF_BITS: return "Wrong ELF word size";
+    case ERR_ELF_ENDIANNESS: return "Wrong ELF endianness";
+    case ERR_CMD_CRC: return "Command CRC error";
+    case ERR_CMD_CHECK: return "Command code check error";
+    case ERR_DATA_CRC: return "Data CRC error";
+    case ERR_DATA_FIFO: return "Data FIFO error";
+    case ERR_BUF_ALIGNMENT: return "Bad buffer alignment";
+    case FR_DISK_ERR: return "Disk error";
+    case FR_TIMEOUT: return "Timeout";
+    }
+    return "Unknown error code";
+    }*/
+
+static void usleep(unsigned us) {
+    uintptr_t cycles0;
+    uintptr_t cycles1;
+    asm volatile ("csrr %0, 0xB00" : "=r" (cycles0));
+    for (;;) {
+        asm volatile ("csrr %0, 0xB00" : "=r" (cycles1));
+        if (cycles1 - cycles0 >= us * 100) break;
+    }
+}
+
+static int sdc_cmd_finish(unsigned cmd, uint32_t * response) {
+  struct sdc_regs * regs = (struct sdc_regs *)SDC;
+  
+    while (1) {
+        unsigned status = regs->cmd_int_status;
+        if (status) {
+            // clear interrupts
+            regs->cmd_int_status = 0;
+            while (regs->software_reset != 0) {}
+            if (status == SDC_CMD_INT_STATUS_CC) {
+                // get response
+                response[0] = regs->response1;
+                response[1] = regs->response2;
+                response[2] = regs->response3;
+                response[3] = regs->response4;
+                return 0;
+            }
+            /* errno = FR_DISK_ERR;
+            if (status & SDC_CMD_INT_STATUS_CTE) errno = FR_TIMEOUT;
+            if (status & SDC_CMD_INT_STATUS_CCRC) errno = ERR_CMD_CRC;
+            if (status & SDC_CMD_INT_STATUS_CIE) errno = ERR_CMD_CHECK;*/
+            break;
+        }
+    }
+    return -1;
+}
+
+static int sdc_data_finish(void) {
+    int status;
+    struct sdc_regs * regs = (struct sdc_regs *)SDC;
+    
+    while ((status = regs->dat_int_status) == 0) {}
+    regs->dat_int_status = 0;
+    while (regs->software_reset != 0) {}
+
+    if (status == SDC_DAT_INT_STATUS_TRS) return 0;
+    /* errno = FR_DISK_ERR;
+    if (status & SDC_DAT_INT_STATUS_CTE) errno = FR_TIMEOUT;
+    if (status & SDC_DAT_INT_STATUS_CRC) errno = ERR_DATA_CRC;
+    if (status & SDC_DAT_INT_STATUS_CFE) errno = ERR_DATA_FIFO;*/
+    return -1;
+}
+
+static int send_data_cmd(unsigned cmd, unsigned arg, void * buf, unsigned blocks, uint32_t * response) {
+  struct sdc_regs * regs = (struct sdc_regs *)SDC;
+  
+  unsigned command = (cmd & 0x3f) << 8;
+    switch (cmd) {
+    case CMD0:
+    case CMD4:
+    case CMD15:
+        // No responce
+        break;
+    case CMD11:
+    case CMD13:
+    case CMD16:
+    case CMD17:
+    case CMD18:
+    case CMD19:
+    case CMD23:
+    case CMD24:
+    case CMD25:
+    case CMD27:
+    case CMD30:
+    case CMD32:
+    case CMD33:
+    case CMD42:
+    case CMD55:
+    case CMD56:
+    case ACMD6:
+        // R1
+        command |= 1; // 48 bits
+        command |= 1 << 3; // resp CRC
+        command |= 1 << 4; // resp OPCODE
+        break;
+    case CMD7:
+    case CMD12:
+    case CMD20:
+    case CMD28:
+    case CMD29:
+    case CMD38:
+        // R1b
+        command |= 1; // 48 bits
+        command |= 1 << 2; // busy
+        command |= 1 << 3; // resp CRC
+        command |= 1 << 4; // resp OPCODE
+        break;
+    case CMD2:
+    case CMD9:
+    case CMD10:
+         // R2
+        command |= 2; // 136 bits
+        command |= 1 << 3; // resp CRC
+        break;
+    case ACMD41:
+        // R3
+        command |= 1; // 48 bits
+        break;
+    case CMD3:
+        // R6
+        command |= 1; // 48 bits
+        command |= 1 << 2; // busy
+        command |= 1 << 3; // resp CRC
+        command |= 1 << 4; // resp OPCODE
+        break;
+    case CMD8:
+        // R7
+        command |= 1; // 48 bits
+        command |= 1 << 3; // resp CRC
+        command |= 1 << 4; // resp OPCODE
+        break;
+    }
+
+    if (blocks) {
+        command |= 1 << 5;
+        if ((intptr_t)buf & 3) {
+          // errno = ERR_BUF_ALIGNMENT;
+            return -1;
+        }
+        regs->dma_addres = (uint64_t)(intptr_t)buf;
+        regs->block_size = 511;
+        regs->block_count = blocks - 1;
+        regs->data_timeout = 0x1FFFFFF;
+    }
+
+    regs->command = command;
+    regs->cmd_timeout = 0xFFFFF;
+    regs->argument = arg;
+
+    if (sdc_cmd_finish(cmd, response) < 0) return -1;
+    if (blocks) return sdc_data_finish();
+
+    return 0;
+}
+
+#define send_cmd(cmd, arg, response) send_data_cmd(cmd, arg, NULL, 0, response)
+
+static BYTE ini_sd(void) {
+  struct sdc_regs * regs = (struct sdc_regs *)SDC;
+    unsigned rca;
+    BYTE card_type;
+    uint32_t response[4];
+
+    /* Reset controller */
+    regs->software_reset = 1;
+    while ((regs->software_reset & 1) == 0) {}
+
+    // This clock divider is meant to initialize the card at
+    // 400kHz
+
+    // 22MHz/400kHz = 55 (base 10) = 0x37 - 0x01 = 0x36
+    regs->clock_divider = 0x36;
+    regs->software_reset = 0;
+    while (regs->software_reset) {}
+    usleep(5000);
+
+    card_type = 0;
+    // drv_status = STA_NOINIT;
+
+    if (regs->capability & SDC_CAPABILITY_SD_RESET) {
+        /* Power cycle SD card */
+        regs->control |= SDC_CONTROL_SD_RESET;
+        usleep(1000000);
+        regs->control &= ~SDC_CONTROL_SD_RESET;
+        usleep(100000);
+    }
+
+    /* Enter Idle state */
+    send_cmd(CMD0, 0, response);
+
+    card_type = CT_SD1;
+    if (send_cmd(CMD8, 0x1AA, response) == 0) {
+        if ((response[0] & 0xfff) != 0x1AA) {
+            // errno = ERR_CMD_CHECK;
+            return -1;
+        }
+        card_type = CT_SD2;
+    }
+
+    /* Wait for leaving idle state (ACMD41 with HCS bit) */
+    while (1) {
+        /* ACMD41, Set Operating Conditions: Host High Capacity & 3.3V */
+      if (send_cmd(CMD55, 0, response) < 0 || send_cmd(ACMD41, 0x40300000, response) < 0) return -1;
+        if (response[0] & (1 << 31)) {
+            if (response[0] & (1 << 30)) card_type |= CT_BLOCK;
+            break;
+        }
+    }
+
+    /* Enter Identification state */
+    if (send_cmd(CMD2, 0, response) < 0) return -1;
+
+    /* Get RCA (Relative Card Address) */
+    rca = 0x1234;
+    if (send_cmd(CMD3, rca << 16, response) < 0) return -1;
+    rca = response[0] >> 16;
+
+    /* Select card */
+    if (send_cmd(CMD7, rca << 16, response) < 0) return -1;
+
+    /* Clock 25MHz */
+    // 22Mhz/2 = 11Mhz
+    regs->clock_divider = 1;
+    usleep(10000);
+
+    /* Bus width 1-bit */
+    regs->control = 0;
+    if (send_cmd(CMD55, rca << 16, response) < 0 || send_cmd(ACMD6, 0, response) < 0) return -1;
+
+    /* Set R/W block length to 512 */
+    if (send_cmd(CMD16, 512, response) < 0) return -1;
+
+    // drv_status &= ~STA_NOINIT;
+    return card_type;
+}
+
+int disk_read(BYTE * buf, LBA_t sector, UINT count, BYTE card_type) {
+
+  /* This is not needed. This has everything to do with the FAT
+     filesystem stuff that I'm not including. All I need to do is
+     initialize the SD card and read from it. Anything in here that is
+     checking for potential errors, I'm going to have to temporarily
+     do without.
+   */
+  // if (!count) return RES_PARERR;
+    /* if (drv_status & STA_NOINIT) return RES_NOTRDY; */
+
+  uint32_t response[4];
+  struct sdc_regs * regs = (struct sdc_regs *)SDC;
+  
+    /* Convert LBA to byte address if needed */
+    if (!(card_type & CT_BLOCK)) sector *= 512;
+    while (count > 0) {
+        UINT bcnt = count > MAX_BLOCK_CNT ? MAX_BLOCK_CNT : count;
+        unsigned bytes = bcnt * 512;
+        if (send_data_cmd(bcnt == 1 ? CMD17 : CMD18, sector, buf, bcnt, response) < 0) return 1;
+        if (bcnt > 1 && send_cmd(CMD12, 0, response) < 0) return 1;
+        sector += (card_type & CT_BLOCK) ? bcnt : bytes;
+        count -= bcnt;
+        buf += bytes;
+    }
+
+    return 0;;
+}
+
+void copyFlash(QWORD address, QWORD * Dst, DWORD numBlocks) {
+  BYTE card_type;
+  int ret = 0;
+  
+  card_type = ini_sd();
+
+  // BYTE * buf = (BYTE *)Dst;
+    
+  // if (disk_read(buf, (LBA_t)address, (UINT)numBlocks, card_type) < 0) /* UART Print function?*/;
+  
+  ret = gpt_load_partitions(card_type);
+}
+
+/*
+int main() {
+  ini_sd();
+  
+  
+  return 0;
+}
+*/
diff --git a/fpga/zsbl/boot.h b/fpga/zsbl/boot.h
new file mode 100644
index 000000000..77d403145
--- /dev/null
+++ b/fpga/zsbl/boot.h
@@ -0,0 +1,26 @@
+#ifndef WALLYBOOT
+#define WALLYBOOT 10000
+
+#include <stdint.h>
+typedef unsigned int    UINT;   /* int must be 16-bit or 32-bit */
+typedef unsigned char   BYTE;   /* char must be 8-bit */
+typedef uint16_t        WORD;   /* 16-bit unsigned integer */
+typedef uint32_t        DWORD;  /* 32-bit unsigned integer */
+typedef uint64_t        QWORD;  /* 64-bit unsigned integer */
+typedef WORD            WCHAR;
+
+typedef QWORD LBA_t;
+
+// Define memory locations of boot images =====================
+// These locations are copied from the generic configuration
+// of OpenSBI. These addresses can be found in:
+// buildroot/output/build/opensbi-0.9/platform/generic/config.mk
+#define FDT_ADDRESS 0x87000000          // FW_JUMP_FDT_ADDR
+#define OPENSBI_ADDRESS 0x80000000      // FW_TEXT_START
+#define KERNEL_ADDRESS 0x80200000       // FW_JUMP_ADDR
+
+// Export disk_read
+int disk_read(BYTE * buf, LBA_t sector, UINT count, BYTE card_type);
+
+#endif // WALLYBOOT
+
diff --git a/fpga/zsbl/copyFlash.c b/fpga/zsbl/copyFlash.c
deleted file mode 100644
index 4165fe21c..000000000
--- a/fpga/zsbl/copyFlash.c
+++ /dev/null
@@ -1,40 +0,0 @@
-///////////////////////////////////////////
-// copyFlash.sv
-//
-// Written: Ross Thompson September 25, 2021
-// Modified: 
-//
-// Purpose: copies flash card into memory
-// 
-// A component of the Wally configurable RISC-V project.
-// 
-// Copyright (C) 2021 Harvey Mudd College & Oklahoma State University
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation
-// files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, 
-// modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software 
-// is furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 
-// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 
-// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT 
-// OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-///////////////////////////////////////////
-
-#include "sdcDriver.h"
-
-void copyFlash(long int blockAddr, long int * Dst, int numBlocks) {
-
-  setSDCCLK(4); // must be even, 1 gives no division.
-  waitInitSDC();
-
-  int index;
-
-  for(index = 0; index < numBlocks; index++) {
-    copySDC512(blockAddr+(index*512), Dst+(index*512/8));
-  }
-  
-    
-}
diff --git a/fpga/zsbl/gpt.c b/fpga/zsbl/gpt.c
index 0c645d70e..97e3e4e46 100644
--- a/fpga/zsbl/gpt.c
+++ b/fpga/zsbl/gpt.c
@@ -1,119 +1,46 @@
 #include "gpt.h"
-
-#include "sdcDriver.h"
-
-#include "uart.h"
+#include "boot.h"
 #include <stddef.h>
 
-int gpt_find_boot_partition(long int* dest, uint32_t size)
-{
-  //int ret = init_sd();
-  int ret;
-  setSDCCLK(4); // must be even, 1 gives no division.
-  waitInitSDC();
-  ret = 0;
-    if (ret != 0) {
-        print_uart("could not initialize sd... exiting\r\n");
-        return -1;
-    }
+/* PSUEDOCODE
 
-    print_uart("sd initialized!\r\n");
+   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.
+   
+*/
 
-    // load LBA1
-    size_t block_size = 512/8;
-    long int lba1_buf[block_size];
+int gpt_load_partitions(BYTE card_type) {
+  // In this version of the GPT partition code
+  // I'm going to assume that the SD card is already initialized.
 
-    //int res = sd_copy(lba1_buf, 1, 1);
-    int res;
-    copySDC512(1, lba1_buf);
-    res = 0;
+  // size_t block_size = 512/8;
+  // long int lba1_buf[block_size];
 
-    if (res != 0)
-    {
-        print_uart("SD card failed!\r\n");
-        print_uart("sd copy return value: ");
-        print_uart_addr(res);
-        print_uart("\r\n");
-        return -2;
-    }
+  BYTE lba1_buf[512];
+  
+  int ret = 0;
+  //ret = disk_read(/* BYTE * buf, LBA_t sector, UINT count, BYTE card_type */);
+  ret = disk_read(lba1_buf, 1, 1, card_type);
 
-    gpt_pth_t *lba1 = (gpt_pth_t *)lba1_buf;
+  /* Possible error handling with UART message
+  if ( ret != 0 ) {
+    
+  }*/
 
-    print_uart("gpt partition table header:");
-    print_uart("\r\n\tsignature:\t");
-    print_uart_addr(lba1->signature);
-    print_uart("\r\n\trevision:\t");
-    print_uart_int(lba1->revision);
-    print_uart("\r\n\tsize:\t\t");
-    print_uart_int(lba1->header_size);
-    print_uart("\r\n\tcrc_header:\t");
-    print_uart_int(lba1->crc_header);
-    print_uart("\r\n\treserved:\t");
-    print_uart_int(lba1->reserved);
-    print_uart("\r\n\tcurrent lba:\t");
-    print_uart_addr(lba1->current_lba);
-    print_uart("\r\n\tbackup lda:\t");
-    print_uart_addr(lba1->backup_lba);
-    print_uart("\r\n\tpartition entries lba:   \t");
-    print_uart_addr(lba1->partition_entries_lba);
-    print_uart("\r\n\tnumber partition entries:\t");
-    print_uart_int(lba1->nr_partition_entries);
-    print_uart("\r\n\tsize partition entries:  \t");
-    print_uart_int(lba1->size_partition_entry);
-    print_uart("\r\n");
+  gpt_pth_t *lba1 = (gpt_pth_t *)lba1_buf;
 
-    long int lba2_buf[block_size];
+  BYTE lba2_buf[512];
+  ret = disk_read(lba2_buf, (LBA_t)lba1->partition_entries_lba, 1, card_type);
 
-    //res = sd_copy(lba2_buf, lba1->partition_entries_lba, 1);
-    copySDC512(lba1->partition_entries_lba, lba2_buf);
-    res = 0;
+  // Load parition entries for the relevant boot partitions.
+  partition_entries_t *fdt = (partition_entries_t *)(lba2_buf);
+  partition_entries_t *opensbi = (partition_entries_t *)(lba2_buf + 128);
+  partition_entries_t *kernel = (partition_entries_t *)(lba2_buf + 256);
 
-    if (res != 0)
-    {
-        print_uart("SD card failed!\r\n");
-        print_uart("sd copy return value: ");
-        print_uart_addr(res);
-        print_uart("\r\n");
-        return -2;
-    }
+  ret = disk_read((BYTE *)FDT_ADDRESS, fdt->first_lba, fdt->last_lba - fdt->first_lba + 1, card_type);
+  ret = disk_read((BYTE *)OPENSBI_ADDRESS, opensbi->first_lba, opensbi->last_lba - opensbi->first_lba + 1, card_type);
+  ret = disk_read((BYTE *)KERNEL_ADDRESS, kernel->first_lba,kernel->last_lba - kernel->first_lba + 1, card_type);
 
-    for (int i = 0; i < 4; i++)
-    {
-        partition_entries_t *part_entry = (partition_entries_t *)(lba2_buf + (i * 128));
-        print_uart("gpt partition entry ");
-        print_uart_byte(i);
-        print_uart("\r\n\tpartition type guid:\t");
-        for (int j = 0; j < 16; j++)
-            print_uart_byte(part_entry->partition_type_guid[j]);
-        print_uart("\r\n\tpartition guid:     \t");
-        for (int j = 0; j < 16; j++)
-            print_uart_byte(part_entry->partition_guid[j]);
-        print_uart("\r\n\tfirst lba:\t");
-        print_uart_addr(part_entry->first_lba);
-        print_uart("\r\n\tlast lba:\t");
-        print_uart_addr(part_entry->last_lba);
-        print_uart("\r\n\tattributes:\t");
-        print_uart_addr(part_entry->attributes);
-        print_uart("\r\n\tname:\t");
-        for (int j = 0; j < 72; j++)
-            print_uart_byte(part_entry->name[j]);
-        print_uart("\r\n");
-    }
-
-    partition_entries_t *boot = (partition_entries_t *)(lba2_buf);
-    print_uart("copying boot image ");
-    //res = sd_copy(dest, boot->first_lba, boot->last_lba - boot->first_lba + 1);
-    copyFlash(boot->first_lba, dest, boot->last_lba - boot->first_lba + 1);
-
-    if (res != 0)
-    {
-        print_uart("SD card failed!\r\n");
-        print_uart("sd copy return value: ");
-        print_uart_addr(res);
-        print_uart("\r\n");
-        return -2;
-    }
-
-    print_uart(" done!\r\n");
-    return 0;
+  return 0;
 }
diff --git a/fpga/zsbl/gpt.h b/fpga/zsbl/gpt.h
index dcc27ae8a..4aefae229 100644
--- a/fpga/zsbl/gpt.h
+++ b/fpga/zsbl/gpt.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <stdint.h>
+#include "boot.h"
 
 // LBA 0: Protective MBR
 // ignored here
@@ -36,4 +37,4 @@ typedef struct partition_entries
 } partition_entries_t;
 
 // Find boot partition and load it to the destination
-int gpt_find_boot_partition(long int* dest, uint32_t size);
+int gpt_load_partitions(BYTE card_type);
diff --git a/fpga/zsbl/linker.x b/fpga/zsbl/linker1000.x
similarity index 99%
rename from fpga/zsbl/linker.x
rename to fpga/zsbl/linker1000.x
index f448109cc..6d9e948a6 100644
--- a/fpga/zsbl/linker.x
+++ b/fpga/zsbl/linker1000.x
@@ -7,7 +7,7 @@ SECTIONS
 {
   /* Read-only sections, merged into text segment: */
   /* init segment to ensure we get a consistent start routine*/
-  . = 0x0000000000000000; 
+  . = 0x0000000000001000; 
   . = ALIGN(0x0); 
   .init : {  
   	*(.init) 
@@ -72,6 +72,7 @@ SECTIONS
   PROVIDE (__etext = .);
   PROVIDE (_etext = .);
   PROVIDE (etext = .);
+  . = 0x0000000000002000;
   .rodata         : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
   .rodata1        : { *(.rodata1) }
   .sdata2         :
diff --git a/fpga/zsbl/main.c b/fpga/zsbl/main.c
deleted file mode 100644
index 898025c30..000000000
--- a/fpga/zsbl/main.c
+++ /dev/null
@@ -1,26 +0,0 @@
-#include "uart.h"
-#include "sdcDriver.h"
-#include "gpt.h"
-
-int main()
-{
-    init_uart(30000000, 115200);
-    print_uart("Hello World!\r\n");
-
-    int res = gpt_find_boot_partition((long int *)0x80000000UL, 2 * 16384);
-
-    if (res == 0)
-    {
-      return 0;
-    }
-
-    while (1)
-    {
-        // do nothing
-    }
-}
-
-void handle_trap(void)
-{
-    // print_uart("trap\r\n");
-}
diff --git a/fpga/zsbl/sdcDriver.c b/fpga/zsbl/sdcDriver.c
deleted file mode 100644
index 45caa42fa..000000000
--- a/fpga/zsbl/sdcDriver.c
+++ /dev/null
@@ -1,69 +0,0 @@
-///////////////////////////////////////////
-// SDC.sv
-//
-// Written: Rose Thompson September 25, 2021
-// Modified: 
-//
-// Purpose: driver for sdc reader.
-// 
-// A component of the Wally configurable RISC-V project.
-// 
-// Copyright (C) 2021 Harvey Mudd College & Oklahoma State University
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation
-// files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, 
-// modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software 
-// is furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 
-// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 
-// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT 
-// OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-///////////////////////////////////////////
-
-
-#include "sdcDriver.h"
-
-#define SDC_MAIL_BOX 0x12100
-
-void copySDC512(long int blockAddr, long int * Dst) {
-
-  waitInitSDC();
-
-  volatile long int * mailBoxAddr;
-  volatile int * mailBoxCmd;
-  volatile int * mailBoxStatus;
-  volatile long int * mailBoxReadData;
-  mailBoxStatus = (int *) (SDC_MAIL_BOX + 0x4);  
-  mailBoxCmd = (int *) (SDC_MAIL_BOX + 0x8);
-  mailBoxAddr = (long int *) (SDC_MAIL_BOX + 0x10);
-  mailBoxReadData = (long int *) (SDC_MAIL_BOX + 0x18);  
-  
-  // write the SDC address register with the blockAddr
-  *mailBoxAddr = blockAddr;
-  *mailBoxCmd = 0x4;
-
-  // wait until the mailbox has valid data
-  // this occurs when status[1] = 0
-  while((*mailBoxStatus & 0x2) == 0x2);
-
-  int index;
-  for(index = 0; index < 512/8; index++) {
-    Dst[index] = *mailBoxReadData;
-  }
-}
-
-volatile void waitInitSDC(){
-  volatile int * mailBoxStatus;
-  mailBoxStatus = (int *) (SDC_MAIL_BOX + 0x4);
-  while((*mailBoxStatus & 0x1) != 0x1);
-}
-
-void setSDCCLK(int divider){
-  divider = (1 - (divider >> 1));
-  volatile int * mailBoxCLK;
-  mailBoxCLK = (int *) (SDC_MAIL_BOX + 0x0);
-  *mailBoxCLK = divider;
-}
diff --git a/fpga/zsbl/sdcDriver.h b/fpga/zsbl/sdcDriver.h
deleted file mode 100644
index 3e7381837..000000000
--- a/fpga/zsbl/sdcDriver.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef __SDCDRIVER_H
-#define __SDCDRIVER_H
-
-
-void copySDC512(long int, long int *);
-volatile void waitInitSDC();
-void setSDCCLK(int);
-void copyFlash(long int, long int *, int);
-
-#endif
diff --git a/fpga/zsbl/smp.h b/fpga/zsbl/smp.h
deleted file mode 100644
index bb037755d..000000000
--- a/fpga/zsbl/smp.h
+++ /dev/null
@@ -1,52 +0,0 @@
-#pragma once
-
-// The hart that non-SMP tests should run on
-#ifndef NONSMP_HART
-#define NONSMP_HART 0
-#endif
-
-// The maximum number of HARTs this code supports
-#define CLINT_CTRL_ADDR 0x2000000
-#ifndef MAX_HARTS
-#define MAX_HARTS 256
-#endif
-#define CLINT_END_HART_IPI CLINT_CTRL_ADDR + (MAX_HARTS * 4)
-
-/* If your test needs to temporarily block multiple-threads, do this:
- *    smp_pause(reg1, reg2)
- *    ... single-threaded work ...
- *    smp_resume(reg1, reg2)
- *    ... multi-threaded work ...
- */
-
-#define smp_pause(reg1, reg2) \
-    li reg2, 0x8;             \
-    csrw mie, reg2;           \
-    li reg1, NONSMP_HART;     \
-    csrr reg2, mhartid;       \
-    bne reg1, reg2, 42f
-
-#define smp_resume(reg1, reg2)   \
-    li reg1, CLINT_CTRL_ADDR;    \
-    41:;                         \
-    li reg2, 1;                  \
-    sw reg2, 0(reg1);            \
-    addi reg1, reg1, 4;          \
-    li reg2, CLINT_END_HART_IPI; \
-    blt reg1, reg2, 41b;         \
-    42:;                         \
-    wfi;                         \
-    csrr reg2, mip;              \
-    andi reg2, reg2, 0x8;        \
-    beqz reg2, 42b;              \
-    li reg1, CLINT_CTRL_ADDR;    \
-    csrr reg2, mhartid;          \
-    slli reg2, reg2, 2;          \
-    add reg2, reg2, reg1;        \
-    sw zero, 0(reg2);            \
-    41:;                         \
-    lw reg2, 0(reg1);            \
-    bnez reg2, 41b;              \
-    addi reg1, reg1, 4;          \
-    li reg2, CLINT_END_HART_IPI; \
-    blt reg1, reg2, 41b
diff --git a/fpga/zsbl/uart.c b/fpga/zsbl/uart.c
deleted file mode 100644
index a8084ee5e..000000000
--- a/fpga/zsbl/uart.c
+++ /dev/null
@@ -1,91 +0,0 @@
-#include "uart.h"
-
-void write_reg_u8(uintptr_t addr, uint8_t value)
-{
-    volatile uint8_t *loc_addr = (volatile uint8_t *)addr;
-    *loc_addr = value;
-}
-
-uint8_t read_reg_u8(uintptr_t addr)
-{
-    return *(volatile uint8_t *)addr;
-}
-
-int is_transmit_empty()
-{
-    return read_reg_u8(UART_LINE_STATUS) & 0x20;
-}
-
-void write_serial(char a)
-{
-    while (is_transmit_empty() == 0) {};
-
-    write_reg_u8(UART_THR, a);
-}
-
-void init_uart(uint32_t freq, uint32_t baud)
-{
-    uint32_t divisor = freq / (baud << 4);
-
-    write_reg_u8(UART_INTERRUPT_ENABLE, 0x00); // Disable all interrupts
-    write_reg_u8(UART_LINE_CONTROL, 0x80);     // Enable DLAB (set baud rate divisor)
-    write_reg_u8(UART_DLAB_LSB, divisor);         // divisor (lo byte)
-    write_reg_u8(UART_DLAB_MSB, (divisor >> 8) & 0xFF);  // divisor (hi byte)
-    write_reg_u8(UART_LINE_CONTROL, 0x03);     // 8 bits, no parity, one stop bit
-    write_reg_u8(UART_FIFO_CONTROL, 0xC7);     // Enable FIFO, clear them, with 14-byte threshold
-    write_reg_u8(UART_MODEM_CONTROL, 0x20);    // Autoflow mode
-}
-
-void print_uart(const char *str)
-{
-    const char *cur = &str[0];
-    while (*cur != '\0')
-    {
-        write_serial((uint8_t)*cur);
-        ++cur;
-    }
-}
-
-uint8_t bin_to_hex_table[16] = {
-    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
-
-void bin_to_hex(uint8_t inp, uint8_t res[2])
-{
-    res[1] = bin_to_hex_table[inp & 0xf];
-    res[0] = bin_to_hex_table[(inp >> 4) & 0xf];
-    return;
-}
-
-void print_uart_int(uint32_t addr)
-{
-    int i;
-    for (i = 3; i > -1; i--)
-    {
-        uint8_t cur = (addr >> (i * 8)) & 0xff;
-        uint8_t hex[2];
-        bin_to_hex(cur, hex);
-        write_serial(hex[0]);
-        write_serial(hex[1]);
-    }
-}
-
-void print_uart_addr(uint64_t addr)
-{
-    int i;
-    for (i = 7; i > -1; i--)
-    {
-        uint8_t cur = (addr >> (i * 8)) & 0xff;
-        uint8_t hex[2];
-        bin_to_hex(cur, hex);
-        write_serial(hex[0]);
-        write_serial(hex[1]);
-    }
-}
-
-void print_uart_byte(uint8_t byte)
-{
-    uint8_t hex[2];
-    bin_to_hex(byte, hex);
-    write_serial(hex[0]);
-    write_serial(hex[1]);
-}
diff --git a/fpga/zsbl/uart.h b/fpga/zsbl/uart.h
deleted file mode 100644
index df3aef9c8..000000000
--- a/fpga/zsbl/uart.h
+++ /dev/null
@@ -1,27 +0,0 @@
-#pragma once
-
-#include <stdint.h>
-
-#define UART_BASE 0x10000000
-
-#define UART_RBR UART_BASE + 0
-#define UART_THR UART_BASE + 0
-#define UART_INTERRUPT_ENABLE UART_BASE + 4
-#define UART_INTERRUPT_IDENT UART_BASE + 8
-#define UART_FIFO_CONTROL UART_BASE + 8
-#define UART_LINE_CONTROL UART_BASE + 12
-#define UART_MODEM_CONTROL UART_BASE + 16
-#define UART_LINE_STATUS UART_BASE + 20
-#define UART_MODEM_STATUS UART_BASE + 24
-#define UART_DLAB_LSB UART_BASE + 0
-#define UART_DLAB_MSB UART_BASE + 4
-
-void init_uart();
-
-void print_uart(const char* str);
-
-void print_uart_int(uint32_t addr);
-
-void print_uart_addr(uint64_t addr);
-
-void print_uart_byte(uint8_t byte);