From a2fa5f96140e30d5ff47c92c5164e0256d92c794 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Fri, 31 Jan 2025 19:29:55 +0100 Subject: [PATCH] PCI: keystone: Specify correct alignment requirement MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The support for a specific iATU alignment was added in commit 2a9a801620ef ("PCI: endpoint: Add support to specify alignment for buffers allocated to BARs"). This commit specifically mentions both that the alignment by each DWC based EP driver should match CX_ATU_MIN_REGION_SIZE, and that AM65x specifically has a 64 KB alignment. This also matches the CX_ATU_MIN_REGION_SIZE value specified in the section "12.2.2.4.7 PCIe Subsystem Address Translation" of the Technical Reference Manual (TRM) for AM65x: https://www.ti.com/lit/ug/spruid7e/spruid7e.pdf This higher value, 1 MB, was obviously an ugly hack used to be able to handle Resizable BARs which have a minimum size of 1 MB. Now when we actually have support for Resizable BARs, let's configure the iATU alignment requirement to the actual requirement. (BARs described as Resizable will still get aligned to 1 MB.) Cc: stable+noautosel@kernel.org # Depends on PCI endpoint Resizable BARs series Fixes: 23284ad677a9 ("PCI: keystone: Add support for PCIe EP in AM654x Platforms") Signed-off-by: Niklas Cassel Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20250131182949.465530-15-cassel@kernel.org Signed-off-by: Manivannan Sadhasivam [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński --- drivers/pci/controller/dwc/pci-keystone.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c index fdc610ec7e5e..76a37368ae4f 100644 --- a/drivers/pci/controller/dwc/pci-keystone.c +++ b/drivers/pci/controller/dwc/pci-keystone.c @@ -970,7 +970,7 @@ static const struct pci_epc_features ks_pcie_am654_epc_features = { .bar[BAR_3] = { .type = BAR_FIXED, .fixed_size = SZ_64K, }, .bar[BAR_4] = { .type = BAR_FIXED, .fixed_size = 256, }, .bar[BAR_5] = { .type = BAR_RESIZABLE, }, - .align = SZ_1M, + .align = SZ_64K, }; static const struct pci_epc_features* -- 2.50.1