Re: [PATCH 3/4] memory: jz4780-nemc: Reduce size of const array

From: Paul Cercueil
Date: Fri Jan 18 2019 - 09:11:05 EST



Hi,

On Fri, Jan 18, 2019 at 5:15 AM, Boris Brezillon <bbrezillon@xxxxxxxxxx> wrote:
On Thu, 17 Jan 2019 19:45:49 -0300
Paul Cercueil <paul@xxxxxxxxxxxxxxx <mailto:paul@xxxxxxxxxxxxxxx>> wrote:

The maximum value found in that array is 15, there's no need to store
these values as uint32_t, a uint8_t is enough.

Is it really worth the additional cast you add in the code?

They're not needed. I had to verify, because it was not obvious to me.
I'll remove them then.


Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx <mailto:paul@xxxxxxxxxxxxxxx>>
---
drivers/memory/jz4780-nemc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/memory/jz4780-nemc.c b/drivers/memory/jz4780-nemc.c
index bcf06adefc96..ef3f20e46590 100644
--- a/drivers/memory/jz4780-nemc.c
+++ b/drivers/memory/jz4780-nemc.c
@@ -161,7 +161,7 @@ static bool jz4780_nemc_configure_bank(struct jz4780_nemc *nemc,
* Conversion of tBP and tAW cycle counts to values supported by the
* hardware (round up to the next supported value).
*/
- static const uint32_t convert_tBP_tAW[] = {
+ static const u8 convert_tBP_tAW[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,

/* 11 - 12 -> 12 cycles */
@@ -232,7 +232,7 @@ static bool jz4780_nemc_configure_bank(struct jz4780_nemc *nemc,
return false;
}

- smcr |= convert_tBP_tAW[cycles] << NEMC_SMCR_TBP_SHIFT;
+ smcr |= (u32)convert_tBP_tAW[cycles] << NEMC_SMCR_TBP_SHIFT;
}

if (of_property_read_u32(node, "ingenic,nemc-tAW", &val) == 0) {
@@ -244,7 +244,7 @@ static bool jz4780_nemc_configure_bank(struct jz4780_nemc *nemc,
return false;
}

- smcr |= convert_tBP_tAW[cycles] << NEMC_SMCR_TAW_SHIFT;
+ smcr |= (u32)convert_tBP_tAW[cycles] << NEMC_SMCR_TAW_SHIFT;
}

if (of_property_read_u32(node, "ingenic,nemc-tSTRV", &val) == 0) {