On 7/26/23 12:26, Simon Horman wrote:
On Tue, Jul 25, 2023 at 06:41:00PM +0200, Gatien Chevallier wrote:
...
diff --git a/drivers/bus/stm32_rifsc.c b/drivers/bus/stm32_rifsc.c
...
+static int stm32_rif_acquire_semaphore(struct stm32_firewall_controller *stm32_firewall_controller,
+ int id)
+{
+ void __iomem *addr = stm32_firewall_controller->mmio + RIFSC_RISC_PER0_SEMCR + 0x8 * id;
+
+ __set_bit(SEMCR_MUTEX, addr);
Hi Gatien,
Sparse seem a bit unhappy about this.
.../stm32_rifsc.c:83:9: warning: cast removes address space '__iomem' of expression
.../stm32_rifsc.c:83:9: warning: incorrect type in argument 2 (different address spaces)
.../stm32_rifsc.c:83:9: expected unsigned long volatile *addr
.../stm32_rifsc.c:83:9: got void [noderef] __iomem *addr
.../stm32_rifsc.c:83:9: warning: incorrect type in argument 2 (different address spaces)
.../stm32_rifsc.c:83:9: expected unsigned long volatile *addr
.../stm32_rifsc.c:83:9: got void [noderef] __iomem *addr
But it's not immediately apparent to me what a good solution is.
Hi Simon,
This is indeed incorrect, set_bit is used to modify bit fields, not
writing to a register. I'll change to writel, as in
stm32_rif_release_semaphore(). Thank you for pointing this out.
Best regards,
Gatien
+
+ /* Check that CID1 has the semaphore */
+ if (stm32_rifsc_is_semaphore_available(addr) ||
+ FIELD_GET(RIFSC_RISC_SCID_MASK, readl(addr)) != RIF_CID1)
+ return -EACCES;
+
+ return 0;
+}
...