From 468df3c8578c3f440ead269bfc8becc7cc8927df Mon Sep 17 00:00:00 2001
From: "fb@frank-buss.de" <fb@frank-buss.de>
Date: Thu, 7 Nov 2019 19:19:54 +0100
Subject: [PATCH] erase flash command added

---
 litex/soc/software/bios/main.c             |  8 ++++++++
 litex/soc/software/include/base/spiflash.h |  1 +
 litex/soc/software/libbase/spiflash.c      | 18 ++++++++++++++++++
 3 files changed, 27 insertions(+)

diff --git a/litex/soc/software/bios/main.c b/litex/soc/software/bios/main.c
index a19e7ce9d..c18cccfb1 100644
--- a/litex/soc/software/bios/main.c
+++ b/litex/soc/software/bios/main.c
@@ -212,6 +212,12 @@ static void fw(char *addr, char *value, char *count)
 	}
 	for (i=0;i<count2;i++) write_to_flash(addr2 + i * 4, (unsigned char *)&value2, 4);
 }
+
+static void ef(void)
+{
+	erase_flash();
+	printf("flash erased\n");
+}
 #endif
 
 #ifdef CSR_ETHPHY_MDIO_W_ADDR
@@ -341,6 +347,7 @@ static void help(void)
 	puts("mc         - copy address space");
 #if (defined CSR_SPIFLASH_BASE && defined SPIFLASH_PAGE_SIZE)
 	puts("fw         - write to flash");
+	puts("ef         - erase whole flash");
 #endif
 #ifdef CSR_ETHPHY_MDIO_W_ADDR
 	puts("mdiow      - write MDIO register");
@@ -404,6 +411,7 @@ static void do_command(char *c)
 	else if(strcmp(token, "mc") == 0) mc(get_token(&c), get_token(&c), get_token(&c));
 #if (defined CSR_SPIFLASH_BASE && defined SPIFLASH_PAGE_SIZE)
 	else if(strcmp(token, "fw") == 0) fw(get_token(&c), get_token(&c), get_token(&c));
+	else if(strcmp(token, "ef") == 0) ef();
 #endif
 #ifdef CSR_ETHPHY_MDIO_W_ADDR
 	else if(strcmp(token, "mdiow") == 0) mdiow(get_token(&c), get_token(&c), get_token(&c));
diff --git a/litex/soc/software/include/base/spiflash.h b/litex/soc/software/include/base/spiflash.h
index a4ff495ab..7d6171bde 100644
--- a/litex/soc/software/include/base/spiflash.h
+++ b/litex/soc/software/include/base/spiflash.h
@@ -3,6 +3,7 @@
 
 void write_to_flash_page(unsigned int addr, const unsigned char *c, unsigned int len);
 void erase_flash_sector(unsigned int addr);
+void erase_flash(void);
 void write_to_flash(unsigned int addr, const unsigned char *c, unsigned int len);
 
 #endif /* __SPIFLASH_H */
diff --git a/litex/soc/software/libbase/spiflash.c b/litex/soc/software/libbase/spiflash.c
index 31d56a106..38a22dce9 100644
--- a/litex/soc/software/libbase/spiflash.c
+++ b/litex/soc/software/libbase/spiflash.c
@@ -8,6 +8,7 @@
 #define WRDI_CMD         0x04
 #define RDSR_CMD         0x05
 #define WREN_CMD         0x06
+#define CHIP_ERASE_CMD   0xc7
 #define SE_CMD           0xd8
 
 #define BITBANG_CLK         (1 << 1)
@@ -89,6 +90,23 @@ void erase_flash_sector(unsigned int addr)
     spiflash_bitbang_en_write(0);
 }
 
+void erase_flash(void)
+{
+    spiflash_bitbang_en_write(1);
+
+    wait_for_device_ready();
+
+    flash_write_byte(WREN_CMD);
+    spiflash_bitbang_write(BITBANG_CS_N);
+
+    flash_write_byte(CHIP_ERASE_CMD);
+    spiflash_bitbang_write(BITBANG_CS_N);
+
+    wait_for_device_ready();
+
+    spiflash_bitbang_en_write(0);
+}
+
 void write_to_flash_page(unsigned int addr, const unsigned char *c, unsigned int len)
 {
     unsigned int i;