From patchwork Sun Jan 31 05:33:12 2010
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: Reset before reading Chip ID
Date: Sun, 31 Jan 2010 04:33:12 -0000
From: Sean Nelson <audiohacked@gmail.com>
X-Patchwork-Id: 857
Message-Id: <4B651618.90307@gmail.com>
To: flashrom <flashrom@flashrom.org>

Add a reset to probe_jedec before we read the Chip's IDs.
Signed-off-by: Sean Nelson <audiohacked@gmail.com>
Acked-by: Anders Juel Jensen <andersjjensen@gmail.com>


diff --git a/jedec.c b/jedec.c
index 055e910..af1d300 100644
--- a/jedec.c
+++ b/jedec.c
@@ -112,26 +112,40 @@ int probe_jedec_common(struct flashchip *flash, unsigned int mask)
 	else if (flash->probe_timing == TIMING_ZERO) { /* No delay. */
 		probe_timing_enter = probe_timing_exit = 0;
 	} else if (flash->probe_timing == TIMING_FIXME) { /* == _IGNORED */
 		printf_debug("Chip lacks correct probe timing information, "
 			     "using default 10mS/40uS. ");
 		probe_timing_enter = 10000;
 		probe_timing_exit = 40;
 	} else {
 		printf("Chip has negative value in probe_timing, failing "
 		       "without chip access\n");
 		return 0;
 	}
 
+	/* Reset chip to a clean slate */
+	if ((flash->feature_bits & FEATURE_SHORT_RESET) == FEATURE_LONG_RESET)
+	{
+		chip_writeb(0xAA, bios + (0x5555 & mask));
+		if (probe_timing_exit)
+			programmer_delay(10);
+		chip_writeb(0x55, bios + (0x2AAA & mask));
+		if (probe_timing_exit)
+			programmer_delay(10);
+	}
+	chip_writeb(0xF0, bios + (0x5555 & mask));
+	if (probe_timing_exit)
+		programmer_delay(probe_timing_exit);
+
 	/* Issue JEDEC Product ID Entry command */
 	chip_writeb(0xAA, bios + (0x5555 & mask));
 	if (probe_timing_enter)
 		programmer_delay(10);
 	chip_writeb(0x55, bios + (0x2AAA & mask));
 	if (probe_timing_enter)
 		programmer_delay(10);
 	chip_writeb(0x90, bios + (0x5555 & mask));
 	if (probe_timing_enter)
 		programmer_delay(probe_timing_enter);
 
 	/* Read product ID */
 	id1 = chip_readb(bios);