From: Jasko-EXT Wojciech Date: Sat, 2 Dec 2023 08:50:15 +0000 (+0530) Subject: PCI: cadence: Clear the ARI Capability Next Function Number of the last function X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=667a006d73fb7320fc6f414b6fe11a998fcf0c28;p=linux.git PCI: cadence: Clear the ARI Capability Next Function Number of the last function Next Function Number field in ARI Capability Register for last function must be zero by default as per the PCIe specification, indicating there is no next higher number function but that's not happening in our case, so this patch clears the Next Function Number field for last function used. [kwilczynski: white spaces update for one define] Link: https://lore.kernel.org/linux-pci/20231202085015.3048516-1-s-vadapalli@ti.com Signed-off-by: Jasko-EXT Wojciech Signed-off-by: Achal Verma Signed-off-by: Siddharth Vadapalli Signed-off-by: Krzysztof WilczyƄski Reviewed-by: Vignesh Raghavendra --- diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 2d0a8d78bffb5..81c50dc64da96 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -565,7 +565,8 @@ static int cdns_pcie_ep_start(struct pci_epc *epc) struct cdns_pcie *pcie = &ep->pcie; struct device *dev = pcie->dev; int max_epfs = sizeof(epc->function_num_map) * 8; - int ret, value, epf; + int ret, epf, last_fn; + u32 reg, value; /* * BIT(0) is hardwired to 1, hence function 0 is always enabled @@ -573,6 +574,17 @@ static int cdns_pcie_ep_start(struct pci_epc *epc) */ cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, epc->function_num_map); + /* + * Next function field in ARI_CAP_AND_CTR register for last function + * should be 0. + * Clearing Next Function Number field for the last function used. + */ + last_fn = find_last_bit(&epc->function_num_map, BITS_PER_LONG); + reg = CDNS_PCIE_CORE_PF_I_ARI_CAP_AND_CTRL(last_fn); + value = cdns_pcie_readl(pcie, reg); + value &= ~CDNS_PCIE_ARI_CAP_NFN_MASK; + cdns_pcie_writel(pcie, reg, value); + if (ep->quirk_disable_flr) { for (epf = 0; epf < max_epfs; epf++) { if (!(epc->function_num_map & BIT(epf))) diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h index 03b96798f858c..7a66a2f815dce 100644 --- a/drivers/pci/controller/cadence/pcie-cadence.h +++ b/drivers/pci/controller/cadence/pcie-cadence.h @@ -130,6 +130,12 @@ #define CDNS_PCIE_EP_FUNC_DEV_CAP_OFFSET 0xc0 #define CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET 0x200 +/* + * Endpoint PF Registers + */ +#define CDNS_PCIE_CORE_PF_I_ARI_CAP_AND_CTRL(fn) (0x144 + (fn) * 0x1000) +#define CDNS_PCIE_ARI_CAP_NFN_MASK GENMASK(15, 8) + /* * Root Port Registers (PCI configuration space for the root port function) */