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authorWolfgang Denk <wd@pollux.(none)>2005-07-30 16:39:27 +0200
committerWolfgang Denk <wd@pollux.(none)>2005-07-30 16:39:27 +0200
commit010162eb729e9ed8233e902313c5f770b89e9202 (patch)
treeb03a605aa6833fb96e2dbc7277a01a9518981e8b /board/pm520/flash.c
parent15f36a5efd31fe608b43dc197ebbd80d3cecbe44 (diff)
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Implement h/w sector protection status synchronization at boot.
The code is provided for, and was tested on, the Yukon/Alaska and PM520 boards only. A bug in flash_real_protect() for the Yukon board was fixed by adding a function that tells if two banks are on one flash chip.
Diffstat (limited to 'board/pm520/flash.c')
-rw-r--r--board/pm520/flash.c97
1 files changed, 95 insertions, 2 deletions
diff --git a/board/pm520/flash.c b/board/pm520/flash.c
index 572cc9b..62700f9 100644
--- a/board/pm520/flash.c
+++ b/board/pm520/flash.c
@@ -75,6 +75,8 @@ static ulong flash_get_size (FPW *addr, flash_info_t *info);
static int write_data (flash_info_t *info, ulong dest, FPW data);
static void flash_get_offsets (ulong base, flash_info_t *info);
void inline spin_wheel (void);
+static void flash_sync_real_protect (flash_info_t * info);
+static unsigned char intel_sector_protected (flash_info_t *info, ushort sector);
/*-----------------------------------------------------------------------
*/
@@ -101,6 +103,9 @@ unsigned long flash_init (void)
break;
}
size += flash_info[i].size;
+
+ /* get the h/w and s/w protection status in sync */
+ flash_sync_real_protect(&flash_info[i]);
}
/* Protect monitor and environment sectors
@@ -138,7 +143,6 @@ static void flash_get_offsets (ulong base, flash_info_t *info)
if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
for (i = 0; i < info->sector_count; i++) {
info->start[i] = base + (i * PHYS_FLASH_SECT_SIZE);
- info->protect[i] = 0;
}
}
}
@@ -270,6 +274,85 @@ static ulong flash_get_size (FPW *addr, flash_info_t *info)
}
+/*
+ * This function gets the u-boot flash sector protection status
+ * (flash_info_t.protect[]) in sync with the sector protection
+ * status stored in hardware.
+ */
+static void flash_sync_real_protect (flash_info_t * info)
+{
+ int i;
+
+ switch (info->flash_id & FLASH_TYPEMASK) {
+
+ case FLASH_28F128J3A:
+ case FLASH_28F640J3A:
+ case FLASH_28F320J3A:
+ for (i = 0; i < info->sector_count; ++i) {
+ info->protect[i] = intel_sector_protected(info, i);
+ }
+ break;
+ default:
+ /* no h/w protect support */
+ break;
+ }
+}
+
+
+/*
+ * checks if "sector" in bank "info" is protected. Should work on intel
+ * strata flash chips 28FxxxJ3x in 8-bit mode.
+ * Returns 1 if sector is protected (or timed-out while trying to read
+ * protection status), 0 if it is not.
+ */
+static unsigned char intel_sector_protected (flash_info_t *info, ushort sector)
+{
+ FPWV *addr;
+ FPWV *lock_conf_addr;
+ ulong start;
+ unsigned char ret;
+
+ /*
+ * first, wait for the WSM to be finished. The rationale for
+ * waiting for the WSM to become idle for at most
+ * CFG_FLASH_ERASE_TOUT is as follows. The WSM can be busy
+ * because of: (1) erase, (2) program or (3) lock bit
+ * configuration. So we just wait for the longest timeout of
+ * the (1)-(3), i.e. the erase timeout.
+ */
+
+ /* wait at least 35ns (W12) before issuing Read Status Register */
+ udelay(1);
+ addr = (FPWV *) info->start[sector];
+ *addr = (FPW) INTEL_STATUS;
+
+ start = get_timer (0);
+ while ((*addr & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED) {
+ if (get_timer (start) > CFG_FLASH_ERASE_TOUT) {
+ *addr = (FPW) INTEL_RESET; /* restore read mode */
+ printf("WSM busy too long, can't get prot status\n");
+ return 1;
+ }
+ }
+
+ /* issue the Read Identifier Codes command */
+ *addr = (FPW) INTEL_READID;
+
+ /* wait at least 35ns (W12) before reading */
+ udelay(1);
+
+ /* Intel example code uses offset of 2 for 16 bit flash */
+ lock_conf_addr = (FPWV *) info->start[sector] + 2;
+ ret = (*lock_conf_addr & (FPW) INTEL_PROTECT) ? 1 : 0;
+
+ /* put flash back in read mode */
+ *addr = (FPW) INTEL_RESET;
+
+ return ret;
+}
+
+
+
/*-----------------------------------------------------------------------
*/
@@ -491,7 +574,7 @@ void inline spin_wheel (void)
* 0 - OK
* 1 - Error (timeout, voltage problems, etc.)
*/
-int flash_real_protect(flash_info_t *info, long sector, int prot)
+int flash_real_protect (flash_info_t *info, long sector, int prot)
{
ulong start;
int i;
@@ -531,6 +614,11 @@ int flash_real_protect(flash_info_t *info, long sector, int prot)
/*
* Clear lock bit command clears all sectors lock bits, so
* we have to restore lock bits of protected sectors.
+ * WARNING: code below re-locks sectors only for one bank (info).
+ * This causes problems on boards where several banks share
+ * the same chip, as sectors in othere banks will be unlocked
+ * but not re-locked. It works fine on pm520 though, as there
+ * is only one chip and one bank.
*/
if (!prot)
{
@@ -553,6 +641,11 @@ int flash_real_protect(flash_info_t *info, long sector, int prot)
}
}
}
+ /*
+ * get the s/w sector protection status in sync with the h/w,
+ * in case something went wrong during the re-locking.
+ */
+ flash_sync_real_protect(info); /* resets flash to read mode */
}
if (flag)