Re: [PATCH v3 6/7] Drivers: hv: vmbus: Get the IRQ number from DT
From: Roman Kisel <hidden>
Date: 2024-07-29 16:36:45
Also in:
linux-acpi, linux-arch, linux-arm-kernel, linux-pci, lkml
On 7/27/2024 1:56 AM, Krzysztof Kozlowski wrote:
On 27/07/2024 00:59, Roman Kisel wrote:quoted
@@ -2338,6 +2372,21 @@ static int vmbus_device_add(struct platform_device *pdev) cur_res = &res->sibling; } + /* + * Hyper-V always assumes DMA cache coherency, and the DMA subsystem + * might default to 'not coherent' on some architectures. + * Avoid high-cost cache coherency maintenance done by the CPU. + */ +#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ + defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ + defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) + + if (!of_property_read_bool(np, "dma-coherent")) + pr_warn("Assuming cache coherent DMA transactions, no 'dma-coherent' node supplied\n");Why do you need this property at all, if it is allways dma-coherent? Are you supporting dma-noncoherent somewhere?
No support for non-coherent. Wanted to do a sanity check. Had better check for dma-noncoherent and warn about that I believe.
Best regards, Krzysztof
-- Thank you, Roman