From a5a0134570c88cd49a6fc97256764cb7fbb93dff Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 25 Oct 2025 23:35:09 +0200 Subject: [PATCH] firmware: scmi: Drop mmu_set_region_dcache_behaviour() misuse MMU region cache behavior configuration for SCMI/SMT mailboxes is platform specific. Even on ARM systems, the mailbox memory may not even be located in any cacheable MMU region and may instead reside in some SRAM. Remove this non-generic cache behavior configuration code from generic code path. It is unlikely that any platform is affected by this change if it did configure its MMU regions correctly on start up. Platforms which might be affected are i.MX94/95 and STM32MP. Fixes: 240720e9052f ("firmware: scmi: mailbox/smt agent device") Fixes: 2a3f161c8b16 ("scmi: correctly configure MMU for SCMI buffer") Fixes: b2ae10970d40 ("firmware: scmi: use PAGE_SIZE alignment for ARM64") Signed-off-by: Marek Vasut Tested-by: Alice Guo Tested-by: Patrice Chotard Signed-off-by: Peng Fan --- drivers/firmware/scmi/smt.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/drivers/firmware/scmi/smt.c b/drivers/firmware/scmi/smt.c index 237871559f0..cd1c0801f72 100644 --- a/drivers/firmware/scmi/smt.c +++ b/drivers/firmware/scmi/smt.c @@ -61,20 +61,6 @@ int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt) if (device_is_compatible(dev, "arm,scmi") && ofnode_has_property(dev_ofnode(dev), "mboxes")) scmi_smt_enable_intr(smt, true); -#ifdef CONFIG_ARM - if (dcache_status()) { - u32 align_size; - - if (IS_ENABLED(CONFIG_ARM64)) - align_size = PAGE_SIZE; - else - align_size = MMU_SECTION_SIZE; - - mmu_set_region_dcache_behaviour(ALIGN_DOWN((uintptr_t)smt->buf, align_size), - ALIGN(smt->size, align_size), DCACHE_OFF); - } -#endif - return 0; } -- 2.47.3