[U-Boot] PATCH mtd CFI flash: timeout calculation underflow if imprecise 1kHz timer: fix
From 6cc63851e5e4c16012d9afad70cedb41b7340de7 Mon Sep 17 00:00:00 2001 From: Renato Andreola renato.andreola@imagos.it Date: Fri, 10 Apr 2009 12:52:55 +0200 Subject: drivers/mtd/cfi_flash: precision and underflow problem in tout calculation
With old configuration it could happen tout=0 if CONFIG_SYS_HZ<1000 solved using an unsigned long long --- drivers/mtd/cfi_flash.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index 175d82a..0aa42a2 100644 --- a/drivers/mtd/cfi_flash.c +++ b/drivers/mtd/cfi_flash.c @@ -660,7 +660,9 @@ static int flash_status_check (flash_info_t * info, flash_sect_t sector, ulong start;
#if CONFIG_SYS_HZ != 1000 - tout *= CONFIG_SYS_HZ/1000; + unsigned long long ull; + ull = tout*CONFIG_SYS_HZ + CONFIG_SYS_HZ/2; + tout = ull/1000; /* Compute: tout *= CONFIG_SYS_HZ/1000; */ #endif
/* Wait for command completion */
On 14:28 Fri 10 Apr , Renato Andreola wrote:
From 6cc63851e5e4c16012d9afad70cedb41b7340de7 Mon Sep 17 00:00:00 2001 From: Renato Andreola renato.andreola@imagos.it Date: Fri, 10 Apr 2009 12:52:55 +0200 Subject: drivers/mtd/cfi_flash: precision and underflow problem in tout calculation
With old configuration it could happen tout=0 if CONFIG_SYS_HZ<1000 solved using an unsigned long long
drivers/mtd/cfi_flash.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index 175d82a..0aa42a2 100644 --- a/drivers/mtd/cfi_flash.c +++ b/drivers/mtd/cfi_flash.c @@ -660,7 +660,9 @@ static int flash_status_check (flash_info_t * info, flash_sect_t sector, ulong start;
#if CONFIG_SYS_HZ != 1000
- tout *= CONFIG_SYS_HZ/1000;
- unsigned long long ull;
- ull = tout*CONFIG_SYS_HZ + CONFIG_SYS_HZ/2;
- tout = ull/1000; /* Compute: tout *= CONFIG_SYS_HZ/1000; */ #endif
drop all of this and fix your CONFIG_SYS_HZ to 1000 (non configurable value) will be better
Best Regards, J.
participants (2)
-
Jean-Christophe PLAGNIOL-VILLARD -
Renato Andreola