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ARM: dts: integrator: Fix DMA ranges

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A recent change affecting the behaviour of phys_to_dma() to
actually require the device tree ranges to work unmasked a
bug in the Integrator DMA ranges.

The PL110 uses the CMA allocator to obtain coherent allocations
from a dedicated 1MB video memory, leading to the following
call chain:

drm_gem_cma_create()
  dma_alloc_attrs()
    dma_alloc_from_dev_coherent()
      __dma_alloc_from_coherent()
        dma_get_device_base()
          phys_to_dma()
            translate_phys_to_dma()

phys_to_dma() by way of translate_phys_to_dma() will nowadays not
provide 1:1 mappings unless the ranges are properly defined in
the device tree and reflected into the dev->dma_range_map.

There is a bug in the device trees because the DMA ranges are
incorrectly specified, and the patch uncovers this bug.

Solution:

- Fix the LB (logic bus) ranges to be 1-to-1 like they should
  have always been.
- Provide a 1:1 dma-ranges attribute to the PL110.
- Mark the PL110 display controller as DMA coherent.

This makes the DMA ranges work right and makes the PL110
framebuffer work again.

Fixes: af6f23b88e ("ARM/dma-mapping: use the generic versions of dma_to_phys/phys_to_dma by default")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220926073311.1610568-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Linus Walleij 2022-09-26 09:33:11 +02:00 committed by Arnd Bergmann
parent 2653853e2a
commit 7bea67a994
No known key found for this signature in database
GPG key ID: 9A6C79EFE60018D9
2 changed files with 5 additions and 4 deletions
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1
arch/arm/boot/dts/integratorap-im-pd1.dts
View file

@ -249,6 +249,7 @@ display@1000000 {
/* 640x480 16bpp @ 25.175MHz is 36827428 bytes/s */
max-memory-bandwidth = <40000000>;
memory-region = <&impd1_ram>;
dma-ranges;
port@0 {
#address-cells = <1>;

8
arch/arm/boot/dts/integratorap.dts
View file

@ -262,7 +262,7 @@ bus@c0000000 {
lm0: bus@c0000000 {
compatible = "simple-bus";
ranges = <0x00000000 0xc0000000 0x10000000>;
dma-ranges = <0x00000000 0x80000000 0x10000000>;
dma-ranges = <0x00000000 0xc0000000 0x10000000>;
reg = <0xc0000000 0x10000000>;
#address-cells = <1>;
#size-cells = <1>;
@ -270,7 +270,7 @@ lm0: bus@c0000000 {
lm1: bus@d0000000 {
compatible = "simple-bus";
ranges = <0x00000000 0xd0000000 0x10000000>;
dma-ranges = <0x00000000 0x80000000 0x10000000>;
dma-ranges = <0x00000000 0xd0000000 0x10000000>;
reg = <0xd0000000 0x10000000>;
#address-cells = <1>;
#size-cells = <1>;
@ -278,7 +278,7 @@ lm1: bus@d0000000 {
lm2: bus@e0000000 {
compatible = "simple-bus";
ranges = <0x00000000 0xe0000000 0x10000000>;
dma-ranges = <0x00000000 0x80000000 0x10000000>;
dma-ranges = <0x00000000 0xe0000000 0x10000000>;
reg = <0xe0000000 0x10000000>;
#address-cells = <1>;
#size-cells = <1>;
@ -286,7 +286,7 @@ lm2: bus@e0000000 {
lm3: bus@f0000000 {
compatible = "simple-bus";
ranges = <0x00000000 0xf0000000 0x10000000>;
dma-ranges = <0x00000000 0x80000000 0x10000000>;
dma-ranges = <0x00000000 0xf0000000 0x10000000>;
reg = <0xf0000000 0x10000000>;
#address-cells = <1>;
#size-cells = <1>;