From 321b5e9afe2d2b31f78b60724d58a9d02888bb57 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sun, 28 May 2017 17:52:56 -0700 Subject: [PATCH] nfp: only try to get to PCIe ctrl memory if BARs are wide enough For accessing PCIe ctrl memory we depend on the BAR aperture being large enough to reach all registers. Since the BAR aperture can be set in the flash make sure the driver won't oops the kernel when the PCIe configuration is unusual. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- .../net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c index 1fde213d5b83..597ac8febb63 100644 --- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c +++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c @@ -119,6 +119,11 @@ #define NFP_PCIE_EM 0x020000 #define NFP_PCIE_SRAM 0x000000 +/* Minimal size of the PCIe cfg memory we depend on being mapped, + * queue controller and DMA controller don't have to be covered. + */ +#define NFP_PCI_MIN_MAP_SIZE 0x080000 + #define NFP_PCIE_P2C_FIXED_SIZE(bar) (1 << (bar)->bitsize) #define NFP_PCIE_P2C_BULK_SIZE(bar) (1 << (bar)->bitsize) #define NFP_PCIE_P2C_GENERAL_TARGET_OFFSET(bar, x) ((x) << ((bar)->bitsize - 2)) @@ -628,8 +633,9 @@ static int enable_bars(struct nfp6000_pcie *nfp, u16 interface) /* Configure, and lock, BAR0.0 for General Target use (MSI-X SRAM) */ bar = &nfp->bar[0]; - bar->iomem = ioremap_nocache(nfp_bar_resource_start(bar), - nfp_bar_resource_len(bar)); + if (nfp_bar_resource_len(bar) >= NFP_PCI_MIN_MAP_SIZE) + bar->iomem = ioremap_nocache(nfp_bar_resource_start(bar), + nfp_bar_resource_len(bar)); if (bar->iomem) { dev_info(nfp->dev, "BAR0.0 RESERVED: General Mapping/MSI-X SRAM\n"); -- 2.20.1