Re: [PATCH] dm: Respect dma-ranges size

["Markus Schneider-Pargmann" <msp@baylibre.com>]

[-- Attachment #1: Type: text/plain, Size: 6726 bytes --]

Hi Marek,

On Mon Mar 16, 2026 at 12:57 AM CET, Marek Vasut wrote:
> Rework dev_phys_to_bus() and dev_bus_to_phys() to respect the size
> of the area specified in dma-ranges DT property. The area outside
> of ranges is remapped 1:1, while the area in the ranges is remapped
> according to the description in the dma-ranges property.
>
> Adjust the test to test the area within the remapped range, not area
> outside the remapped range, which was incorrect.
>

Should this have a Fixes tag?

> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

Not a big expert, but this looks good to me:

Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>


One detail inline:

> ---
> Cc: "Markus Schneider-Pargmann (TI.com)" <msp@baylibre.com>
> Cc: Andrew Goodbody <andrew.goodbody@linaro.org>
> Cc: Casey Connolly <casey.connolly@linaro.org>
> Cc: Mattijs Korpershoek <mkorpershoek@kernel.org>
> Cc: Michal Simek <michal.simek@amd.com>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Tom Rini <trini@konsulko.com>
> Cc: u-boot@lists.denx.de
> ---
>  drivers/core/device.c |  6 +++++-
>  include/dm/device.h   | 17 ++++++-----------
>  include/phys2bus.h    | 12 +++++++++---
>  test/dm/core.c        |  6 +++---
>  test/dm/phys2bus.c    |  4 ++--
>  5 files changed, 25 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/core/device.c b/drivers/core/device.c
> index 779f371b9d5..d365204ba11 100644
> --- a/drivers/core/device.c
> +++ b/drivers/core/device.c
> @@ -473,7 +473,11 @@ static int device_get_dma_constraints(struct udevice *dev)
>  		return ret;
>  	}
>  
> -	dev_set_dma_offset(dev, cpu - bus);
> +#if CONFIG_IS_ENABLED(DM_DMA)
> +	dev->dma_cpu = cpu;
> +	dev->dma_bus = bus;
> +	dev->dma_size = size;
> +#endif
>  
>  	return 0;
>  }
> diff --git a/include/dm/device.h b/include/dm/device.h
> index 678cd83c271..7bcf6df2892 100644
> --- a/include/dm/device.h
> +++ b/include/dm/device.h
> @@ -166,8 +166,9 @@ enum {
>   *		When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
>   *		add to this list. Memory so-allocated will be freed
>   *		automatically when the device is removed / unbound
> - * @dma_offset: Offset between the physical address space (CPU's) and the
> - *		device's bus address space
> + * @dma_cpu: DMA physical address space (CPU's)
> + * @dma_bus: DMA device's bus address space
> + * @dma_size: DMA window size
>   * @iommu: IOMMU device associated with this device
>   */
>  struct udevice {
> @@ -196,7 +197,9 @@ struct udevice {
>  	struct list_head devres_head;
>  #endif
>  #if CONFIG_IS_ENABLED(DM_DMA)
> -	ulong dma_offset;
> +	phys_addr_t dma_cpu;
> +	dma_addr_t dma_bus;
> +	u64 dma_size;
>  #endif
>  #if CONFIG_IS_ENABLED(IOMMU)
>  	struct udevice *iommu;
> @@ -272,14 +275,6 @@ static inline __attribute_const__ ofnode dev_ofnode(const struct udevice *dev)
>  /* Returns non-zero if the device is active (probed and not removed) */
>  #define device_active(dev)	(dev_get_flags(dev) & DM_FLAG_ACTIVATED)
>  
> -#if CONFIG_IS_ENABLED(DM_DMA)
> -#define dev_set_dma_offset(_dev, _offset)	_dev->dma_offset = _offset
> -#define dev_get_dma_offset(_dev)		_dev->dma_offset
> -#else
> -#define dev_set_dma_offset(_dev, _offset)
> -#define dev_get_dma_offset(_dev)		0
> -#endif
> -
>  static inline __attribute_const__ int dev_of_offset(const struct udevice *dev)
>  {
>  #if CONFIG_IS_ENABLED(OF_REAL)
> diff --git a/include/phys2bus.h b/include/phys2bus.h
> index 866b8b51a8c..80fa88adae1 100644
> --- a/include/phys2bus.h
> +++ b/include/phys2bus.h
> @@ -21,17 +21,23 @@ static inline unsigned long bus_to_phys(unsigned long bus)
>  }
>  #endif
>  
> -#if CONFIG_IS_ENABLED(DM)
> +#if CONFIG_IS_ENABLED(DM_DMA)

This is not related to the code changes right?

Best
Markus

>  #include <dm/device.h>
>  
>  static inline dma_addr_t dev_phys_to_bus(struct udevice *dev, phys_addr_t phys)
>  {
> -	return phys - dev_get_dma_offset(dev);
> +	/* If the PA is in the remap range, apply remap. */
> +	if (phys >= dev->dma_cpu && phys < dev->dma_cpu + dev->dma_size)
> +		phys -= dev->dma_cpu - dev->dma_bus;
> +	return phys;
>  }
>  
>  static inline phys_addr_t dev_bus_to_phys(struct udevice *dev, dma_addr_t bus)
>  {
> -	return bus + dev_get_dma_offset(dev);
> +	/* If the DA is in the remap range, apply remap. */
> +	if (bus >= dev->dma_bus && bus < dev->dma_bus + dev->dma_size)
> +		bus += dev->dma_cpu - dev->dma_bus;
> +	return bus;
>  }
>  #else
>  #define dev_phys_to_bus(_, _addr)	_addr
> diff --git a/test/dm/core.c b/test/dm/core.c
> index 78ee14af228..bb9f526b064 100644
> --- a/test/dm/core.c
> +++ b/test/dm/core.c
> @@ -1248,13 +1248,13 @@ static int dm_test_dma_offset(struct unit_test_state *uts)
>         node = ofnode_path("/mmio-bus@0");
>         ut_assert(ofnode_valid(node));
>         ut_assertok(uclass_get_device_by_ofnode(UCLASS_TEST_BUS, node, &dev));
> -       ut_asserteq_64(0, dev->dma_offset);
> +       ut_asserteq_64(0, dev->dma_cpu - dev->dma_bus);
>  
>         /* Device behind a bus with dma-ranges */
>         node = ofnode_path("/mmio-bus@0/subnode@0");
>         ut_assert(ofnode_valid(node));
>         ut_assertok(uclass_get_device_by_ofnode(UCLASS_TEST_FDT, node, &dev));
> -       ut_asserteq_64(-0x10000000ULL, dev->dma_offset);
> +       ut_asserteq_64(-0x10000000ULL, dev->dma_cpu - dev->dma_bus);
>  
>         /* This one has no dma-ranges */
>         node = ofnode_path("/mmio-bus@1");
> @@ -1263,7 +1263,7 @@ static int dm_test_dma_offset(struct unit_test_state *uts)
>         node = ofnode_path("/mmio-bus@1/subnode@0");
>         ut_assert(ofnode_valid(node));
>         ut_assertok(uclass_get_device_by_ofnode(UCLASS_TEST_FDT, node, &dev));
> -       ut_asserteq_64(0, dev->dma_offset);
> +       ut_asserteq_64(0, dev->dma_cpu - dev->dma_bus);
>  
>         return 0;
>  }
> diff --git a/test/dm/phys2bus.c b/test/dm/phys2bus.c
> index 0f30c7e37fd..67f33904943 100644
> --- a/test/dm/phys2bus.c
> +++ b/test/dm/phys2bus.c
> @@ -28,8 +28,8 @@ static int dm_test_phys_to_bus(struct unit_test_state *uts)
>  	node = ofnode_path("/mmio-bus@0/subnode@0");
>  	ut_assert(ofnode_valid(node));
>  	ut_assertok(uclass_get_device_by_ofnode(UCLASS_TEST_FDT, node, &dev));
> -	ut_asserteq_addr((void*)0x100fffffULL, (void*)dev_phys_to_bus(dev, 0xfffff));
> -	ut_asserteq_addr((void*)0xfffffULL, (void*)(ulong)dev_bus_to_phys(dev, 0x100fffff));
> +	ut_asserteq_addr((void*)0x1003ffffULL, (void*)dev_phys_to_bus(dev, 0x3ffff));
> +	ut_asserteq_addr((void*)0x3ffffULL, (void*)(ulong)dev_bus_to_phys(dev, 0x1003ffff));
>  
>  	return 0;
>  }


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 289 bytes --]