summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--jedec.c31
1 files changed, 27 insertions, 4 deletions
diff --git a/jedec.c b/jedec.c
index 8ba7b06..800d9d2 100644
--- a/jedec.c
+++ b/jedec.c
@@ -33,7 +33,7 @@ uint8_t oddparity(uint8_t val)
return (val ^ (val >> 1)) & 0x1;
}
-void toggle_ready_jedec(chipaddr dst)
+void toggle_ready_jedec_common(chipaddr dst, int delay)
{
unsigned int i = 0;
uint8_t tmp1, tmp2;
@@ -41,12 +41,33 @@ void toggle_ready_jedec(chipaddr dst)
tmp1 = chip_readb(dst) & 0x40;
while (i++ < 0xFFFFFFF) {
+ if (delay)
+ programmer_delay(delay);
tmp2 = chip_readb(dst) & 0x40;
if (tmp1 == tmp2) {
break;
}
tmp1 = tmp2;
}
+ if (i > 0x100000)
+ printf_debug("%s: excessive loops, i=0x%x\n", __func__, i);
+}
+
+void toggle_ready_jedec(chipaddr dst)
+{
+ toggle_ready_jedec_common(dst, 0);
+}
+
+/* Some chips require a minimum delay between toggle bit reads.
+ * The Winbond W39V040C wants 50 ms between reads on sector erase toggle,
+ * but experiments show that 2 ms are already enough. Pick a safety factor
+ * of 4 and use an 8 ms delay.
+ * Given that erase is slow on all chips, it is recommended to use
+ * toggle_ready_jedec_slow in erase functions.
+ */
+void toggle_ready_jedec_slow(chipaddr dst)
+{
+ toggle_ready_jedec_common(dst, 8 * 1000);
}
void data_polling_jedec(chipaddr dst, uint8_t data)
@@ -62,6 +83,8 @@ void data_polling_jedec(chipaddr dst, uint8_t data)
break;
}
}
+ if (i > 0x100000)
+ printf_debug("%s: excessive loops, i=0x%x\n", __func__, i);
}
void start_program_jedec(chipaddr bios)
@@ -184,7 +207,7 @@ int erase_sector_jedec(struct flashchip *flash, unsigned int page, unsigned int
programmer_delay(10);
/* wait for Toggle bit ready */
- toggle_ready_jedec(bios);
+ toggle_ready_jedec_slow(bios);
if (check_erased_range(flash, page, pagesize)) {
fprintf(stderr,"ERASE FAILED!\n");
@@ -213,7 +236,7 @@ int erase_block_jedec(struct flashchip *flash, unsigned int block, unsigned int
programmer_delay(10);
/* wait for Toggle bit ready */
- toggle_ready_jedec(bios);
+ toggle_ready_jedec_slow(bios);
if (check_erased_range(flash, block, blocksize)) {
fprintf(stderr,"ERASE FAILED!\n");
@@ -242,7 +265,7 @@ int erase_chip_jedec(struct flashchip *flash)
chip_writeb(0x10, bios + 0x5555);
programmer_delay(10);
- toggle_ready_jedec(bios);
+ toggle_ready_jedec_slow(bios);
if (check_erased_range(flash, 0, total_size)) {
fprintf(stderr,"ERASE FAILED!\n");