[PATCH] dmaengine: ste_dma40: Preserve the LCPA I/O address space

[Linus Walleij <linusw@kernel.org>]

The LCPA area is mapped with devm_ioremap(), but lcpa_base and the
per-channel lcpa pointer lack __iomem annotations. This loses the I/O
address space and makes sparse warn when d40_current_addr() assigns
LCPA register addresses to its __iomem pointers.

Annotate both pointers and the LCPA argument of d40_log_lli_lcpa_write()
to preserve the I/O address space from the mapping to the register
accessors. This also fixes the existing LCPA read and write warnings
without changing the generated code.

Fixes: c80edceff29e ("dmaengine: ste_dma40: Fix cyclic transfer residue")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202610090216.pjMRxhRL-lkp@intel.com/
Assisted-by: LLM
Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 drivers/dma/ste_dma40.c    | 4 ++--
 drivers/dma/ste_dma40_ll.c | 8 ++++----
 drivers/dma/ste_dma40_ll.h | 2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index d3cc2c512ccf..74dd4cbdc3c0 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -509,7 +509,7 @@ struct d40_chan {
 	u32				 src_def_cfg;
 	u32				 dst_def_cfg;
 	struct d40_def_lcsp		 log_def;
-	struct d40_log_lli_full		*lcpa;
+	struct d40_log_lli_full __iomem	*lcpa;
 	/* Runtime reconfiguration */
 	dma_addr_t			runtime_addr;
 	enum dma_transfer_direction	runtime_direction;
@@ -617,7 +617,7 @@ struct d40_base {
 	/* Physical half channels */
 	struct d40_phy_res		 *phy_res;
 	struct d40_lcla_pool		  lcla_pool;
-	void				 *lcpa_base;
+	void __iomem			 *lcpa_base;
 	dma_addr_t			  phy_lcpa;
 	resource_size_t			  lcpa_size;
 	struct kmem_cache		 *desc_slab;
diff --git a/drivers/dma/ste_dma40_ll.c b/drivers/dma/ste_dma40_ll.c
index 4c489b126cb2..3be7f5b1abb0 100644
--- a/drivers/dma/ste_dma40_ll.c
+++ b/drivers/dma/ste_dma40_ll.c
@@ -333,10 +333,10 @@ static void d40_log_lli_link(struct d40_log_lli *lli_dst,
 		(dlos << D40_MEM_LCSP1_SLOS_POS);
 }
 
-void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
-			   struct d40_log_lli *lli_dst,
-			   struct d40_log_lli *lli_src,
-			   int next, unsigned int flags)
+void d40_log_lli_lcpa_write(struct d40_log_lli_full __iomem *lcpa,
+			    struct d40_log_lli *lli_dst,
+			    struct d40_log_lli *lli_src,
+			    int next, unsigned int flags)
 {
 	d40_log_lli_link(lli_dst, lli_src, next, flags);
 
diff --git a/drivers/dma/ste_dma40_ll.h b/drivers/dma/ste_dma40_ll.h
index 55090cb31057..ca9d07649361 100644
--- a/drivers/dma/ste_dma40_ll.h
+++ b/drivers/dma/ste_dma40_ll.h
@@ -455,7 +455,7 @@ int d40_log_sg_to_lli(struct scatterlist *sg,
 		      u32 lcsp13, /* src or dst*/
 		      u32 data_width1, u32 data_width2);
 
-void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
+void d40_log_lli_lcpa_write(struct d40_log_lli_full __iomem *lcpa,
 			    struct d40_log_lli *lli_dst,
 			    struct d40_log_lli *lli_src,
 			    int next, unsigned int flags);

---
base-commit: 511afae96d89847f753fcab6b3a597f0281be9d5
change-id: 20261010-dma40-smatch-fix-42fce06d4f25

Best regards,
-- 
Linus Walleij <linusw@kernel.org>