diff --git a/fw/rtl/sd/sd_dma.v b/fw/rtl/sd/sd_dma.v
index 3a4e29c..64167ad 100644
--- a/fw/rtl/sd/sd_dma.v
+++ b/fw/rtl/sd/sd_dma.v
@@ -4,8 +4,8 @@ module sd_dma (
 
     input [3:0] i_dma_bank,
     input [23:0] i_dma_address,
-    input [14:0] i_dma_length,
-    output [14:0] o_dma_left,
+    input [17:0] i_dma_length,
+    output [17:0] o_dma_left,
     input i_dma_load_bank_address,
     input i_dma_load_length,
     input i_dma_direction,
@@ -47,14 +47,14 @@ module sd_dma (
         end
     end
 
-    reg [14:0] r_remaining;
+    reg [17:0] r_remaining;
 
     assign o_dma_left = r_remaining;
 
     always @(posedge i_clk) begin
         if (i_dma_load_length && !o_dma_busy) begin
             r_remaining <= i_dma_length;
-        end else if (w_request_successful && r_remaining > 15'd0) begin
+        end else if (w_request_successful && r_remaining > 18'd0) begin
             r_remaining <= r_remaining - 1'd1;
         end
     end
@@ -66,7 +66,7 @@ module sd_dma (
             if (i_dma_start && !o_dma_busy) begin
                 o_dma_busy <= 1'b1;
             end
-            if (i_dma_stop || (w_request_successful && r_remaining == 15'd0)) begin
+            if (i_dma_stop || (w_request_successful && r_remaining == 18'd0)) begin
                 o_dma_busy <= 1'b0;
             end
         end
diff --git a/fw/rtl/sd/sd_interface.v b/fw/rtl/sd/sd_interface.v
index 80709d6..ac2d622 100644
--- a/fw/rtl/sd/sd_interface.v
+++ b/fw/rtl/sd/sd_interface.v
@@ -187,8 +187,8 @@ module sd_interface (
 
     wire [3:0] w_dma_bank;
     wire [23:0] w_dma_address;
-    wire [14:0] w_dma_length;
-    wire [14:0] w_dma_left;
+    wire [17:0] w_dma_length;
+    wire [17:0] w_dma_left;
     wire w_dma_load_bank_address;
     wire w_dma_load_length;
     wire w_dma_direction;
diff --git a/fw/rtl/sd/sd_regs.v b/fw/rtl/sd/sd_regs.v
index 0ef8629..4ae4434 100644
--- a/fw/rtl/sd/sd_regs.v
+++ b/fw/rtl/sd/sd_regs.v
@@ -38,10 +38,10 @@ module sd_regs (
 
     output reg [3:0] o_dma_bank,
     output reg [23:0] o_dma_address,
-    output reg [14:0] o_dma_length,
+    output reg [17:0] o_dma_length,
     input [3:0] i_dma_bank,
     input [23:0] i_dma_address,
-    input [14:0] i_dma_left,
+    input [17:0] i_dma_left,
     output reg o_dma_load_bank_address,
     output reg o_dma_load_length,
     output reg o_dma_direction,
@@ -73,7 +73,7 @@ module sd_regs (
     always @(*) begin
         o_dma_bank = i_data[31:28];
         o_dma_address = i_data[25:2];
-        o_dma_length = i_data[14:0];
+        o_dma_length = i_data[17:0];
         o_dma_load_bank_address = w_write_request && !i_address[3] && (i_address[2:0] == SD_REG_DMA_ADDR);
         o_dma_load_length = w_write_request && !i_address[3] && (i_address[2:0] == SD_REG_DMA_LEN);
         o_busy = 1'b0;
@@ -210,7 +210,7 @@ module sd_regs (
                     end
 
                     SD_REG_DMA_LEN: begin
-                        o_data <= {17'd0, i_dma_left};
+                        o_data <= {14'd0, i_dma_left};
                     end
                 endcase
             end else begin
diff --git a/sw/bootloader/src/sc64/sc64_regs.h b/sw/bootloader/src/sc64/sc64_regs.h
index 10a5094..399bb64 100644
--- a/sw/bootloader/src/sc64/sc64_regs.h
+++ b/sw/bootloader/src/sc64/sc64_regs.h
@@ -165,8 +165,8 @@ typedef struct sc64_sd_registers_s {
 #define SC64_SD_DMA_BANK_GET(addr)          (((addr) >> 28) & 0xF)
 #define SC64_SD_DMA_BANK_ADDR(b, a)         ((((b) & 0xF) << 28) | ((a) & 0x3FFFFFC))
 
-#define SC64_SD_DMA_LEN_GET(len)            (((len) & 0x7FFF) * 4)
-#define SC64_SD_DMA_LEN(l)                  ((((l) / 4) - 1) & 0x7FFF)
+#define SC64_SD_DMA_LEN_GET(len)            (((len) & 0x3FFFF) * 4)
+#define SC64_SD_DMA_LEN(l)                  ((((l) / 4) - 1) & 0x3FFFF)
 
 
 #endif
diff --git a/sw/bootloader/src/sc64/sc64_sd.c b/sw/bootloader/src/sc64/sc64_sd.c
index c51a7f3..a8ae0ca 100644
--- a/sw/bootloader/src/sc64/sc64_sd.c
+++ b/sw/bootloader/src/sc64/sc64_sd.c
@@ -379,7 +379,6 @@ sc64_sd_err_t sc64_sd_read_sectors(uint32_t starting_sector, size_t count, void
 }
 
 sc64_sd_err_t sc64_sd_read_sectors_dma(uint32_t starting_sector, size_t count, uint8_t bank, uint32_t address) {
-    size_t num_transfers;
     size_t sectors_left;
     uint32_t current_sector;
     uint32_t current_address;
@@ -397,7 +396,6 @@ sc64_sd_err_t sc64_sd_read_sectors_dma(uint32_t starting_sector, size_t count, u
         return E_PAR_ERROR;
     }
 
-    num_transfers = (count / 2048) + 1;
     sectors_left = count;
     current_sector = starting_sector;
     if (!sd_card_type_block) {
@@ -405,7 +403,7 @@ sc64_sd_err_t sc64_sd_read_sectors_dma(uint32_t starting_sector, size_t count, u
     }
     current_address = address;
 
-    for (size_t i = 0; i < num_transfers; i++) {
+    do {
         num_blocks = (sectors_left > 2048) ? 2048 : sectors_left;
 
         platform_pi_io_write(&SC64_SD->DMA_ADDR, SC64_SD_DMA_BANK_ADDR(bank, current_address));
@@ -450,9 +448,10 @@ sc64_sd_err_t sc64_sd_read_sectors_dma(uint32_t starting_sector, size_t count, u
 
         while (platform_pi_io_read(&SC64_SD->DMA_SCR) & SC64_SD_DMA_SCR_BUSY);
 
-        current_sector += sd_card_type_block ? 1 : SD_BLOCK_SIZE;
+        sectors_left -= num_blocks;
+        current_sector += num_blocks * (sd_card_type_block ? 1 : SD_BLOCK_SIZE);
         current_address += num_blocks * SD_BLOCK_SIZE;
-    }
+    } while (sectors_left > 0);
 
     return E_OK;
 }