| Message ID | 20220629215944.397952-2-heiko@sntech.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | riscv: implement Zicbom-based CMO instructions + the t-head variant | expand |
Looks good assuming the new binding is accepted by the maintainers:
Reviewed-by: Christoph Hellwig <hch@lst.de>
On Wed, Jun 29, 2022 at 4:00 PM Heiko Stuebner <heiko@sntech.de> wrote: > > of_dma_is_coherent() currently expects the architecture to be > non-coherent and some devices being coherent getting marked > as such with the dma-coherent devicetree property. > > For PowerPC CONFIG_OF_DMA_DEFAULT_COHERENT was added which currently > makes of_dma_is_coherent() always return true but doesn't handle > the case of the architecture being coherent but some devices not. > > So modify the function to also check for dma-noncoherent and > set a suitable default return value. If CONFIG_OF_DMA_DEFAULT_COHERENT > is set the value starts with true and finding dma-noncoherent will > set it to false and without CONFIG_OF_DMA_DEFAULT_COHERENT, the > behaviour is reversed. > > Signed-off-by: Heiko Stuebner <heiko@sntech.de> > --- > drivers/of/address.c | 17 ++++++++++------- > 1 file changed, 10 insertions(+), 7 deletions(-) Reviewed-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/of/address.c b/drivers/of/address.c index 94f017d808c4..96f0a12e507c 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -1045,26 +1045,29 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np) * * It returns true if "dma-coherent" property was found * for this device in the DT, or if DMA is coherent by - * default for OF devices on the current platform. + * default for OF devices on the current platform and no + * "dma-noncoherent" property was found for this device. */ bool of_dma_is_coherent(struct device_node *np) { struct device_node *node; - - if (IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT)) - return true; + bool is_coherent = IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT); node = of_node_get(np); while (node) { if (of_property_read_bool(node, "dma-coherent")) { - of_node_put(node); - return true; + is_coherent = true; + break; + } + if (of_property_read_bool(node, "dma-noncoherent")) { + is_coherent = false; + break; } node = of_get_next_dma_parent(node); } of_node_put(node); - return false; + return is_coherent; } EXPORT_SYMBOL_GPL(of_dma_is_coherent);
of_dma_is_coherent() currently expects the architecture to be non-coherent and some devices being coherent getting marked as such with the dma-coherent devicetree property. For PowerPC CONFIG_OF_DMA_DEFAULT_COHERENT was added which currently makes of_dma_is_coherent() always return true but doesn't handle the case of the architecture being coherent but some devices not. So modify the function to also check for dma-noncoherent and set a suitable default return value. If CONFIG_OF_DMA_DEFAULT_COHERENT is set the value starts with true and finding dma-noncoherent will set it to false and without CONFIG_OF_DMA_DEFAULT_COHERENT, the behaviour is reversed. Signed-off-by: Heiko Stuebner <heiko@sntech.de> --- drivers/of/address.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-)