This is my attempt at fixing one of the regressions we've seen[1] after
the introduction of per-zone atomic pools.
This combined with "dma-pool: Do not allocate pool memory from CMA"[2]
should fix the boot issues on Jeremy's RPi4 setup.
[1] https://lkml.org/lkml/2020/7/2/974
[2] https://lkml.org/lkml/2020/7/8/1108
---
Nicolas Saenz Julienne (4):
dma-direct: Provide function to check physical memory area validity
dma-pool: Get rid of dma_in_atomic_pool()
dma-pool: Introduce dma_guess_pool()
dma-pool: Make sure atomic pool suits device
include/linux/dma-direct.h | 1 +
kernel/dma/direct.c | 2 +-
kernel/dma/pool.c | 76 +++++++++++++++++++++++++++-----------
3 files changed, 56 insertions(+), 23 deletions(-)
--
2.27.0
dma_coherent_ok() checks if a physical memory area fits a device's DMA
constraints.
Signed-off-by: Nicolas Saenz Julienne <[email protected]>
---
include/linux/dma-direct.h | 1 +
kernel/dma/direct.c | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index cdfa400f89b3..cb23a8305132 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -69,6 +69,7 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
u64 dma_direct_get_required_mask(struct device *dev);
gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
u64 *phys_mask);
+bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size);
void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs);
void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 93f578a8e613..4de864cacd22 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -70,7 +70,7 @@ gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
return 0;
}
-static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
+bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
{
return phys_to_dma_direct(dev, phys) + size - 1 <=
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
--
2.27.0
Hi,
I have merged this to a 5.8 tree along with "dma-pool: Only allocate
from CMA when in the same memory zone" and tested it in various ACPI/DT
combinations, particularly on the RPI4. It seems to be working fine.
So thanks for your time and effort clearing this up!
Tested-by: Jeremy Linton <[email protected]>
On 7/9/20 11:19 AM, Nicolas Saenz Julienne wrote:
> This is my attempt at fixing one of the regressions we've seen[1] after
> the introduction of per-zone atomic pools.
>
> This combined with "dma-pool: Do not allocate pool memory from CMA"[2]
> should fix the boot issues on Jeremy's RPi4 setup.
>
> [1] https://lkml.org/lkml/2020/7/2/974
> [2] https://lkml.org/lkml/2020/7/8/1108
>
> ---
>
> Nicolas Saenz Julienne (4):
> dma-direct: Provide function to check physical memory area validity
> dma-pool: Get rid of dma_in_atomic_pool()
> dma-pool: Introduce dma_guess_pool()
> dma-pool: Make sure atomic pool suits device
>
> include/linux/dma-direct.h | 1 +
> kernel/dma/direct.c | 2 +-
> kernel/dma/pool.c | 76 +++++++++++++++++++++++++++-----------
> 3 files changed, 56 insertions(+), 23 deletions(-)
>