From c07703124faa16274eb014502bc3614da6c82e5c Mon Sep 17 00:00:00 2001
From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Thu, 25 Jun 2020 13:46:39 +0200
Subject: [PATCH] liblitesdcard/sdcard_read: enable multiple block read.

>10MB/s read speed with a 25MHz clock.
---
 litex/soc/software/liblitesdcard/sdcard.c | 29 ++++++++++-------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/litex/soc/software/liblitesdcard/sdcard.c b/litex/soc/software/liblitesdcard/sdcard.c
index 1329433d..b3281959 100644
--- a/litex/soc/software/liblitesdcard/sdcard.c
+++ b/litex/soc/software/liblitesdcard/sdcard.c
@@ -484,25 +484,22 @@ int sdcard_init(void) {
 
 void sdcard_read(uint32_t sector, uint32_t count, uint8_t* buf)
 {
-	uint32_t i;
-	for (i=0; i<count; i++) {
-		/* Initialize DMA Writer */
-		sdreader_enable_write(0);
-		sdreader_base_write((uint32_t) buf);
-		sdreader_length_write(512);
-		sdreader_enable_write(1);
-
-		/* Read Single Block from SDCard */
-		sdcard_set_block_count(1);
+	/* Initialize DMA Writer */
+	sdreader_enable_write(0);
+	sdreader_base_write((uint32_t) buf);
+	sdreader_length_write(512*count);
+	sdreader_enable_write(1);
+
+	/* Read Block(s) from SDCard */
+	sdcard_set_block_count(count);
+	if (count > 0)
+		sdcard_read_multiple_block(sector, count);
+	else
 		sdcard_read_single_block(sector);
 
-		/* Wait for DMA Writer to complete */
-		while ((sdreader_done_read() & 0x1) == 0);
+	/* Wait for DMA Writer to complete */
+	while ((sdreader_done_read() & 0x1) == 0);
 
-		/* Update buf/sector */
-		buf    += 512;
-		sector += 1;
-	}
 	flush_cpu_dcache(); /* FIXME */
 }
 
-- 
2.30.2