===================================================================
@@ -437,7 +437,7 @@ static int spi_nor_parse_bfpt(struct spi
struct sfdp_bfpt bfpt;
size_t len;
int i, cmd, err;
- u32 addr;
+ u32 addr, val;
u16 half;
u8 erase_mask;
@@ -472,21 +472,21 @@ static int spi_nor_parse_bfpt(struct spi
}
/* Flash Memory Density (in bits). */
- params->size = bfpt.dwords[BFPT_DWORD(2)];
- if (params->size & BIT(31)) {
- params->size &= ~BIT(31);
+ val = bfpt.dwords[BFPT_DWORD(2)];
+ if (val & BIT(31)) {
+ val &= ~BIT(31);
/*
* Prevent overflows on params->size. Anyway, a NOR of 2^64
* bits is unlikely to exist so this error probably means
* the BFPT we are reading is corrupted/wrong.
*/
- if (params->size > 63)
+ if (val > 63)
return -EINVAL;
- params->size = 1ULL << params->size;
+ params->size = 1ULL << val;
} else {
- params->size++;
+ params->size = val + 1;
}
params->size >>= 3; /* Convert to bytes. */
@@ -553,10 +553,10 @@ static int spi_nor_parse_bfpt(struct spi
params);
/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
- params->page_size = bfpt.dwords[BFPT_DWORD(11)];
- params->page_size &= BFPT_DWORD11_PAGE_SIZE_MASK;
- params->page_size >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
- params->page_size = 1U << params->page_size;
+ val = bfpt.dwords[BFPT_DWORD(11)];
+ val &= BFPT_DWORD11_PAGE_SIZE_MASK;
+ val >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
+ params->page_size = 1U << val;
/* Quad Enable Requirements. */
switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
Despite of how spi_nor_parse_bfpt() abuses the structure fields during their calculation, gcc manages to make some decent code out of that. :-) Yet adding a local variable to store the BFPT DWORDs during calculations still saves 12 bytes of the object code (AArch64 gcc 4.8.5)... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> --- This patch is against the 'spi-nor/next' branch of the MTD 'linux.git' repo. drivers/mtd/spi-nor/sfdp.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)