Re: [PATCH v2 4/6] iommu/ipmmu-vmsa: Calculate context registers' offset instead of a macro

[Geert Uytterhoeven]

On Tue, Oct 15, 2019 at 2:10 PM Yoshihiro Shimoda
 wrote:
> Since we will have changed memory mapping of the IPMMU in the future,
> this patch uses ipmmu_features values instead of a macro to
> calculate context registers offset. No behavior change.
>
> Signed-off-by: Yoshihiro Shimoda 

Reviewed-by: Geert Uytterhoeven 

Gr{oetje,eeting}s,

Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

[PATCH v2 4/6] iommu/ipmmu-vmsa: Calculate context registers' offset instead of a macro

[Yoshihiro Shimoda]

Since we will have changed memory mapping of the IPMMU in the future,
this patch uses ipmmu_features values instead of a macro to
calculate context registers offset. No behavior change.

Signed-off-by: Yoshihiro Shimoda 
---
 drivers/iommu/ipmmu-vmsa.c | 11 ---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index c60b31d..37bb4b7 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -50,6 +50,8 @@ struct ipmmu_features {
bool twobit_imttbcr_sl0;
bool reserved_context;
bool cache_snoop;
+   unsigned int ctx_offset_base;
+   unsigned int ctx_offset_stride;
 };
 
 struct ipmmu_vmsa_device {
@@ -99,8 +101,6 @@ static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
 
 #define IM_NS_ALIAS_OFFSET 0x800
 
-#define IM_CTX_SIZE0x40
-
 /* MMU "context" registers */
 #define IMCTR  0x  /* R-Car Gen2/3 */
 #define IMCTR_INTEN(1 << 2)/* R-Car Gen2/3 */
@@ -193,7 +193,8 @@ static void ipmmu_write(struct ipmmu_vmsa_device *mmu, 
unsigned int offset,
 static unsigned int ipmmu_ctx_reg(struct ipmmu_vmsa_device *mmu,
  unsigned int context_id, unsigned int reg)
 {
-   return context_id * IM_CTX_SIZE + reg;
+   return mmu->features->ctx_offset_base +
+  context_id * mmu->features->ctx_offset_stride + reg;
 }
 
 static u32 ipmmu_ctx_read(struct ipmmu_vmsa_device *mmu,
@@ -937,6 +938,8 @@ static const struct ipmmu_features ipmmu_features_default = 
{
.twobit_imttbcr_sl0 = false,
.reserved_context = false,
.cache_snoop = true,
+   .ctx_offset_base = 0,
+   .ctx_offset_stride = 0x40,
 };
 
 static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
@@ -948,6 +951,8 @@ static const struct ipmmu_features ipmmu_features_rcar_gen3 
= {
.twobit_imttbcr_sl0 = true,
.reserved_context = true,
.cache_snoop = false,
+   .ctx_offset_base = 0,
+   .ctx_offset_stride = 0x40,
 };
 
 static const struct of_device_id ipmmu_of_ids[] = {
-- 
2.7.4