From: Felix Fietkau <nbd@openwrt.org>
Date: Wed, 28 Feb 2007 01:14:42 +0000 (+0000)
Subject: add a patch to revert recent breakage in the intel cfi flash driver (fixes #1140)
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=4273579814731e1718c0902bb216f776482517c0;p=openwrt%2Fstaging%2F981213.git

add a patch to revert recent breakage in the intel cfi flash driver (fixes #1140)

SVN-Revision: 6420
---

diff --git a/target/linux/generic-2.6/patches/009-revert_intel_flash_breakage.patch b/target/linux/generic-2.6/patches/009-revert_intel_flash_breakage.patch
new file mode 100644
index 0000000000..ea06360c48
--- /dev/null
+++ b/target/linux/generic-2.6/patches/009-revert_intel_flash_breakage.patch
@@ -0,0 +1,169 @@
+--- linux.old/drivers/mtd/chips/cfi_cmdset_0001.c	2007-02-13 02:41:50.816650352 +0100
++++ linux.dev/drivers/mtd/chips/cfi_cmdset_0001.c	2007-02-13 02:42:13.782159064 +0100
+@@ -908,7 +908,7 @@
+ 
+ static int __xipram xip_wait_for_operation(
+ 		struct map_info *map, struct flchip *chip,
+-		unsigned long adr, unsigned int chip_op_time )
++		unsigned long adr, int *chip_op_time )
+ {
+ 	struct cfi_private *cfi = map->fldrv_priv;
+ 	struct cfi_pri_intelext *cfip = cfi->cmdset_priv;
+@@ -917,7 +917,7 @@
+ 	flstate_t oldstate, newstate;
+ 
+        	start = xip_currtime();
+-	usec = chip_op_time * 8;
++	usec = *chip_op_time * 8;
+ 	if (usec == 0)
+ 		usec = 500000;
+ 	done = 0;
+@@ -1027,8 +1027,8 @@
+ #define XIP_INVAL_CACHED_RANGE(map, from, size)  \
+ 	INVALIDATE_CACHED_RANGE(map, from, size)
+ 
+-#define INVAL_CACHE_AND_WAIT(map, chip, cmd_adr, inval_adr, inval_len, usec) \
+-	xip_wait_for_operation(map, chip, cmd_adr, usec)
++#define INVAL_CACHE_AND_WAIT(map, chip, cmd_adr, inval_adr, inval_len, p_usec) \
++	xip_wait_for_operation(map, chip, cmd_adr, p_usec)
+ 
+ #else
+ 
+@@ -1040,65 +1040,65 @@
+ static int inval_cache_and_wait_for_operation(
+ 		struct map_info *map, struct flchip *chip,
+ 		unsigned long cmd_adr, unsigned long inval_adr, int inval_len,
+-		unsigned int chip_op_time)
++		int *chip_op_time )
+ {
+ 	struct cfi_private *cfi = map->fldrv_priv;
+ 	map_word status, status_OK = CMD(0x80);
+-	int chip_state = chip->state;
+-	unsigned int timeo, sleep_time;
++	int z, chip_state = chip->state;
++	unsigned long timeo;
+ 
+ 	spin_unlock(chip->mutex);
+ 	if (inval_len)
+ 		INVALIDATE_CACHED_RANGE(map, inval_adr, inval_len);
++	if (*chip_op_time)
++		cfi_udelay(*chip_op_time);
+ 	spin_lock(chip->mutex);
+ 
+-	/* set our timeout to 8 times the expected delay */
+-	timeo = chip_op_time * 8;
+-	if (!timeo)
+-		timeo = 500000;
+-	sleep_time = chip_op_time / 2;
++	timeo = *chip_op_time * 8 * HZ / 1000000;
++	if (timeo < HZ/2)
++		timeo = HZ/2;
++	timeo += jiffies;
+ 
++	z = 0;
+ 	for (;;) {
++		if (chip->state != chip_state) {
++			/* Someone's suspended the operation: sleep */
++			DECLARE_WAITQUEUE(wait, current);
++
++			set_current_state(TASK_UNINTERRUPTIBLE);
++			add_wait_queue(&chip->wq, &wait);
++			spin_unlock(chip->mutex);
++			schedule();
++			remove_wait_queue(&chip->wq, &wait);
++			timeo = jiffies + (HZ / 2); /* FIXME */
++			spin_lock(chip->mutex);
++			continue;
++		}
++
+ 		status = map_read(map, cmd_adr);
+ 		if (map_word_andequal(map, status, status_OK, status_OK))
+ 			break;
+ 
+-		if (!timeo) {
++		/* OK Still waiting */
++		if (time_after(jiffies, timeo)) {
+ 			map_write(map, CMD(0x70), cmd_adr);
+ 			chip->state = FL_STATUS;
+ 			return -ETIME;
+ 		}
+ 
+-		/* OK Still waiting. Drop the lock, wait a while and retry. */
++		/* Latency issues. Drop the lock, wait a while and retry */
++		z++;
+ 		spin_unlock(chip->mutex);
+-		if (sleep_time >= 1000000/HZ) {
+-			/*
+-			 * Half of the normal delay still remaining
+-			 * can be performed with a sleeping delay instead
+-			 * of busy waiting.
+-			 */
+-			msleep(sleep_time/1000);
+-			timeo -= sleep_time;
+-			sleep_time = 1000000/HZ;
+-		} else {
+-			udelay(1);
+-			cond_resched();
+-			timeo--;
+-		}
++		cfi_udelay(1);
+ 		spin_lock(chip->mutex);
+-
+-		while (chip->state != chip_state) {
+-			/* Someone's suspended the operation: sleep */
+-			DECLARE_WAITQUEUE(wait, current);
+-			set_current_state(TASK_UNINTERRUPTIBLE);
+-			add_wait_queue(&chip->wq, &wait);
+-			spin_unlock(chip->mutex);
+-			schedule();
+-			remove_wait_queue(&chip->wq, &wait);
+-			spin_lock(chip->mutex);
+-		}
+ 	}
+ 
++	if (!z) {
++		if (!--(*chip_op_time))
++			*chip_op_time = 1;
++	} else if (z > 1)
++		++(*chip_op_time);
++
+ 	/* Done and happy. */
+  	chip->state = FL_STATUS;
+ 	return 0;
+@@ -1107,7 +1107,8 @@
+ #endif
+ 
+ #define WAIT_TIMEOUT(map, chip, adr, udelay) \
+-	INVAL_CACHE_AND_WAIT(map, chip, adr, 0, 0, udelay);
++	({ int __udelay = (udelay); \
++	   INVAL_CACHE_AND_WAIT(map, chip, adr, 0, 0, &__udelay); })
+ 
+ 
+ static int do_point_onechip (struct map_info *map, struct flchip *chip, loff_t adr, size_t len)
+@@ -1331,7 +1332,7 @@
+ 
+ 	ret = INVAL_CACHE_AND_WAIT(map, chip, adr,
+ 				   adr, map_bankwidth(map),
+-				   chip->word_write_time);
++				   &chip->word_write_time);
+ 	if (ret) {
+ 		xip_enable(map, chip, adr);
+ 		printk(KERN_ERR "%s: word write error (status timeout)\n", map->name);
+@@ -1568,7 +1569,7 @@
+ 
+ 	ret = INVAL_CACHE_AND_WAIT(map, chip, cmd_adr,
+ 				   adr, len,
+-				   chip->buffer_write_time);
++				   &chip->buffer_write_time);
+ 	if (ret) {
+ 		map_write(map, CMD(0x70), cmd_adr);
+ 		chip->state = FL_STATUS;
+@@ -1703,7 +1704,7 @@
+ 
+ 	ret = INVAL_CACHE_AND_WAIT(map, chip, adr,
+ 				   adr, len,
+-				   chip->erase_time);
++				   &chip->erase_time);
+ 	if (ret) {
+ 		map_write(map, CMD(0x70), adr);
+ 		chip->state = FL_STATUS;