[PATCH] accel/habanalabs/gaudi2: Constify several structures

From: Christophe JAILLET
Date: Mon Jul 22 2024 - 16:41:24 EST


These structures are not modified in this driver.

Constifying this structure moves about 8 ko of data to a read-only section,
so increase overall security.

On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
191214 134180 456 325850 4f8da drivers/accel/habanalabs/gaudi2/gaudi2.o

After:
=====
text data bss dec hex filename
198862 126532 456 325850 4f8da drivers/accel/habanalabs/gaudi2/gaudi2.o


Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Compile tested-only.

A much bigger step, would be to constify gaudi2_irq_map_table.
But drivers/accel/habanalabs/include/gaudi2/gaudi2_async_ids_map_extended.h
states that this is a generated file. So I just report it here, could
someone modify the software that generates this file.

This would constify an additional 110 ko of data. Not too bad, for just 5
more letters!

text data bss dec hex filename
310314 14884 456 325654 4f816 drivers/accel/habanalabs/gaudi2/gaudi2.o
---
drivers/accel/habanalabs/gaudi2/gaudi2.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/accel/habanalabs/gaudi2/gaudi2.c b/drivers/accel/habanalabs/gaudi2/gaudi2.c
index a38b88baadf2..40aebae29ab1 100644
--- a/drivers/accel/habanalabs/gaudi2/gaudi2.c
+++ b/drivers/accel/habanalabs/gaudi2/gaudi2.c
@@ -173,7 +173,7 @@ struct gaudi2_razwi_info {
char *eng_name;
};

-static struct gaudi2_razwi_info common_razwi_info[] = {
+static const struct gaudi2_razwi_info common_razwi_info[] = {
{RAZWI_INITIATOR_ID_X_Y(2, 4, 0), mmDCORE0_RTR0_CTRL_BASE,
GAUDI2_DCORE0_ENGINE_ID_DEC_0, "DEC0"},
{RAZWI_INITIATOR_ID_X_Y(2, 4, 4), mmDCORE0_RTR0_CTRL_BASE,
@@ -338,7 +338,7 @@ static struct gaudi2_razwi_info common_razwi_info[] = {
GAUDI2_ENGINE_ID_PSOC, "PSOC"}
};

-static struct gaudi2_razwi_info mme_razwi_info[] = {
+static const struct gaudi2_razwi_info mme_razwi_info[] = {
/* MME X high coordinate is N/A, hence using only low coordinates */
{RAZWI_INITIATOR_ID_X_Y_LOW(7, 4), mmDCORE0_RTR5_CTRL_BASE,
GAUDI2_DCORE0_ENGINE_ID_MME, "MME0_WAP0"},
@@ -2108,7 +2108,7 @@ struct hbm_mc_error_causes {
char cause[50];
};

-static struct hl_special_block_info gaudi2_special_blocks[] = GAUDI2_SPECIAL_BLOCKS;
+static const struct hl_special_block_info gaudi2_special_blocks[] = GAUDI2_SPECIAL_BLOCKS;

/* Special blocks iterator is currently used to configure security protection bits,
* and read global errors. Most HW blocks are addressable and those who aren't (N/A)-
@@ -2116,14 +2116,14 @@ static struct hl_special_block_info gaudi2_special_blocks[] = GAUDI2_SPECIAL_BLO
* and global error reading, since currently they both share the same settings.
* Once it changes, we must remember to use separate configurations for either one.
*/
-static int gaudi2_iterator_skip_block_types[] = {
+static const int gaudi2_iterator_skip_block_types[] = {
GAUDI2_BLOCK_TYPE_PLL,
GAUDI2_BLOCK_TYPE_EU_BIST,
GAUDI2_BLOCK_TYPE_HBM,
GAUDI2_BLOCK_TYPE_XFT
};

-static struct range gaudi2_iterator_skip_block_ranges[] = {
+static const struct range gaudi2_iterator_skip_block_ranges[] = {
/* Skip all PSOC blocks except for PSOC_GLOBAL_CONF */
{mmPSOC_I2C_M0_BASE, mmPSOC_EFUSE_BASE},
{mmPSOC_BTL_BASE, mmPSOC_MSTR_IF_RR_SHRD_HBW_BASE},
@@ -2132,7 +2132,7 @@ static struct range gaudi2_iterator_skip_block_ranges[] = {
{mmCPU_TIMESTAMP_BASE, mmCPU_MSTR_IF_RR_SHRD_HBW_BASE}
};

-static struct hbm_mc_error_causes hbm_mc_spi[GAUDI2_NUM_OF_HBM_MC_SPI_CAUSE] = {
+static const struct hbm_mc_error_causes hbm_mc_spi[GAUDI2_NUM_OF_HBM_MC_SPI_CAUSE] = {
{HBM_MC_SPI_TEMP_PIN_CHG_MASK, "temperature pins changed"},
{HBM_MC_SPI_THR_ENG_MASK, "temperature-based throttling engaged"},
{HBM_MC_SPI_THR_DIS_ENG_MASK, "temperature-based throttling disengaged"},
@@ -8300,9 +8300,9 @@ static void gaudi2_check_if_razwi_happened(struct hl_device *hdev)
gaudi2_ack_module_razwi_event_handler(hdev, RAZWI_ROT, mod_idx, 0, NULL);
}

-static int gaudi2_psoc_razwi_get_engines(struct gaudi2_razwi_info *razwi_info, u32 array_size,
- u32 axuser_xy, u32 *base, u16 *eng_id,
- char *eng_name)
+static int gaudi2_psoc_razwi_get_engines(const struct gaudi2_razwi_info *razwi_info,
+ u32 array_size, u32 axuser_xy,
+ u32 *base, u16 *eng_id, char *eng_name)
{

int i, num_of_eng = 0;
--
2.45.2