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.
diff --git a/board/alaska/flash.c b/board/alaska/flash.c
index 48c9472..383491f 100644
--- a/board/alaska/flash.c
+++ b/board/alaska/flash.c
@@ -64,7 +64,6 @@
#define FLASH_CYCLE2 0x02aa
#define WR_BLOCK 0x20
-
/*-----------------------------------------------------------------------
* Functions
*/
@@ -74,6 +73,9 @@
static int write_word_amd (flash_info_t * info, FPWV * 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);
+static unsigned char same_chip_banks (int bank1, int bank2);
/*-----------------------------------------------------------------------
*/
@@ -115,6 +117,9 @@
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
@@ -167,7 +172,6 @@
if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
for (i = 0; i < info->sector_count; i++) {
info->start[i] = base + (i * PHYS_INTEL_SECT_SIZE);
- info->protect[i] = 0;
}
}
}
@@ -305,6 +309,98 @@
}
+/*
+ * 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:
+ for (i = 0; i < info->sector_count; ++i) {
+ info->protect[i] = intel_sector_protected(info, i);
+ }
+ break;
+ case FLASH_AM040:
+ 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 4 for 8-bit flash */
+ lock_conf_addr = (FPWV *) info->start[sector] + 4;
+ ret = (*lock_conf_addr & (FPW) INTEL_PROTECT) ? 1 : 0;
+
+ /* put flash back in read mode */
+ *addr = (FPW) INTEL_RESET;
+
+ return ret;
+}
+
+
+/*
+ * Checks if "bank1" and "bank2" are on the same chip. Returns 1 if they
+ * are and 0 otherwise.
+ */
+static unsigned char same_chip_banks (int bank1, int bank2)
+{
+ unsigned char same_chip[CFG_MAX_FLASH_BANKS][CFG_MAX_FLASH_BANKS] = {
+ {1, 1, 0, 0},
+ {1, 1, 0, 0},
+ {0, 0, 1, 1},
+ {0, 0, 1, 1}
+ };
+ return same_chip[bank1][bank2];
+}
+
+
/*-----------------------------------------------------------------------
*/
int flash_erase (flash_info_t * info, int s_first, int s_last)
@@ -729,7 +825,9 @@
int flash_real_protect (flash_info_t * info, long sector, int prot)
{
ulong start;
- int i;
+ int i, j;
+ int curr_bank;
+ int bank;
int rc = 0;
FPWV *addr = (FPWV *) (info->start[sector]);
int flag = disable_interrupts ();
@@ -779,23 +877,54 @@
* we have to restore lock bits of protected sectors.
*/
if (!prot) {
- for (i = 0; i < info->sector_count; i++) {
- if (info->protect[i]) {
- start = get_timer (0);
- addr = (FPWV *) (info->start[i]);
- *addr = INTEL_LOCKBIT; /* Sector lock bit */
- *addr = INTEL_PROTECT; /* set */
- while ((*addr & INTEL_FINISHED) !=
- INTEL_FINISHED) {
- if (get_timer (start) >
- CFG_FLASH_UNLOCK_TOUT) {
- printf ("Flash lock bit operation timed out\n");
- rc = 1;
- break;
+ /*
+ * re-locking must be done for all banks that belong on one
+ * FLASH chip, as all the sectors on the chip were unlocked
+ * by INTEL_LOCKBIT/INTEL_CONFIRM commands. (let's hope
+ * that banks never span chips, in particular chips which
+ * support h/w protection differently).
+ */
+
+ /* find the current bank number */
+ curr_bank = CFG_MAX_FLASH_BANKS + 1;
+ for (j = 0; j < CFG_MAX_FLASH_BANKS; ++j) {
+ if (&flash_info[j] == info) {
+ curr_bank = j;
+ }
+ }
+ if (curr_bank == CFG_MAX_FLASH_BANKS + 1) {
+ printf("Error: can't determine bank number!\n");
+ }
+
+ for (bank = 0; bank < CFG_MAX_FLASH_BANKS; ++bank) {
+ if (!same_chip_banks(curr_bank, bank)) {
+ continue;
+ }
+ info = &flash_info[bank];
+ for (i = 0; i < info->sector_count; i++) {
+ if (info->protect[i]) {
+ start = get_timer (0);
+ addr = (FPWV *) (info->start[i]);
+ *addr = INTEL_LOCKBIT; /* Sector lock bit */
+ *addr = INTEL_PROTECT; /* set */
+ while ((*addr & INTEL_FINISHED) !=
+ INTEL_FINISHED) {
+ if (get_timer (start) >
+ CFG_FLASH_UNLOCK_TOUT) {
+ printf ("Flash lock bit operation timed out\n");
+ rc = 1;
+ break;
+ }
}
}
}
}
+
+ /*
+ * 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)