From f4f7eb43c5238fd2636a8e310394ed9920627ab3 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:12 +0530 Subject: PCI: Set error response data when config read fails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a PCI config read fails, most PCI host bridges fabricate ~0 data to complete the CPU read. But some host bridges do not; their drivers may only return an error from the pci_ops.read() method. In PCI_OP_READ() and PCI_USER_READ_CONFIG(), use PCI_SET_ERROR_RESPONSE() to set the data value to indicate an error when pci_ops.read() fails. This means the host bridge driver no longer needs to fabricate error data when they detect errors. This makes error response fabrication consistent and helps in removal of a lot of repeated code. Suggested-by: Rob Herring Link: https://lore.kernel.org/r/4188fc5465631ce0d472d1423de3d9fb2f09b8ff.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Reviewed-by: Rob Herring Reviewed-by: Pali Rohár --- drivers/pci/access.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 46935695cfb9..eac0765d8bed 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -42,7 +42,10 @@ int noinline pci_bus_read_config_##size \ if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; \ pci_lock_config(flags); \ res = bus->ops->read(bus, devfn, pos, len, &data); \ - *value = (type)data; \ + if (res) \ + PCI_SET_ERROR_RESPONSE(value); \ + else \ + *value = (type)data; \ pci_unlock_config(flags); \ return res; \ } @@ -228,7 +231,10 @@ int pci_user_read_config_##size \ ret = dev->bus->ops->read(dev->bus, dev->devfn, \ pos, sizeof(type), &data); \ raw_spin_unlock_irq(&pci_lock); \ - *val = (type)data; \ + if (ret) \ + PCI_SET_ERROR_RESPONSE(val); \ + else \ + *val = (type)data; \ return pcibios_err_to_errno(ret); \ } \ EXPORT_SYMBOL_GPL(pci_user_read_config_##size); -- cgit From 9bc9310c8f641234a81f139414fdb5b20b1df8c4 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:13 +0530 Subject: PCI: Use PCI_SET_ERROR_RESPONSE() for disconnected devices A config read from a PCI device that doesn't exist or doesn't respond causes a PCI error. There's no real data to return to satisfy the CPU read, so most hardware fabricates ~0 data. Use PCI_SET_ERROR_RESPONSE() to set the error response when we think the device has already been disconnected. This helps unify PCI error response checking and make error checks consistent and easier to find. Link: https://lore.kernel.org/r/29db0a6874716db80757e4e3cdd03562f13eb0cb.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/access.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/access.c b/drivers/pci/access.c index eac0765d8bed..e1add90494ec 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -529,7 +529,7 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword); int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val); @@ -539,7 +539,7 @@ EXPORT_SYMBOL(pci_read_config_byte); int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_word(dev->bus, dev->devfn, where, val); @@ -550,7 +550,7 @@ int pci_read_config_dword(const struct pci_dev *dev, int where, u32 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val); -- cgit From 316df7062a7926e315507e2d5b7a23331a3bfa67 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:14 +0530 Subject: PCI: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/1b2edb060cf19b45f70645b331e6c08c9ba798c0.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Reviewed-by: Rob Herring --- drivers/pci/access.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/access.c b/drivers/pci/access.c index e1add90494ec..a92637627845 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -83,10 +83,8 @@ int pci_generic_config_read(struct pci_bus *bus, unsigned int devfn, void __iomem *addr; addr = bus->ops->map_bus(bus, devfn, where); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } if (size == 1) *val = readb(addr); @@ -125,10 +123,8 @@ int pci_generic_config_read32(struct pci_bus *bus, unsigned int devfn, void __iomem *addr; addr = bus->ops->map_bus(bus, devfn, where & ~0x3); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = readl(addr); -- cgit From 658f7ecd6785e4b4344216596ac432b8f6af0893 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:15 +0530 Subject: PCI: thunder: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/22f471b638276422926c49f3d42ac41bc7b28b3d.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pci-thunder-ecam.c | 46 +++++++++++-------------------- drivers/pci/controller/pci-thunder-pem.c | 4 +-- 2 files changed, 17 insertions(+), 33 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pci-thunder-ecam.c b/drivers/pci/controller/pci-thunder-ecam.c index e9d5ca245f5e..b5bd10a62adb 100644 --- a/drivers/pci/controller/pci-thunder-ecam.c +++ b/drivers/pci/controller/pci-thunder-ecam.c @@ -41,10 +41,9 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus, } if (where_a == 0x4) { addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */ - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + v = readl(addr); v &= ~0xf; v |= 2; /* EA entry-1. Base-L */ @@ -56,10 +55,9 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus, u32 barl_rb; addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */ - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + barl_orig = readl(addr + 0); writel(0xffffffff, addr + 0); barl_rb = readl(addr + 0); @@ -72,10 +70,9 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus, } if (where_a == 0xc) { addr = bus->ops->map_bus(bus, devfn, bar + 4); /* BAR 1 */ - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + v = readl(addr); /* EA entry-3. Base-H */ set_val(v, where, size, val); return PCIBIOS_SUCCESSFUL; @@ -104,10 +101,8 @@ static int thunder_ecam_p2_config_read(struct pci_bus *bus, unsigned int devfn, } addr = bus->ops->map_bus(bus, devfn, where_a); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } v = readl(addr); @@ -135,10 +130,8 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, int where_a = where & ~3; addr = bus->ops->map_bus(bus, devfn, 0xc); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } v = readl(addr); @@ -146,10 +139,8 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, cfg_type = (v >> 16) & 0x7f; addr = bus->ops->map_bus(bus, devfn, 8); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } class_rev = readl(addr); if (class_rev == 0xffffffff) @@ -176,10 +167,8 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, } addr = bus->ops->map_bus(bus, devfn, 0); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } vendor_device = readl(addr); if (vendor_device == 0xffffffff) @@ -196,10 +185,9 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, bool is_tns = (vendor_device == 0xa01f177d); addr = bus->ops->map_bus(bus, devfn, 0x70); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + /* E_CAP */ v = readl(addr); has_msix = (v & 0xff00) != 0; @@ -211,10 +199,9 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, } if (where_a == 0xb0) { addr = bus->ops->map_bus(bus, devfn, where_a); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + v = readl(addr); if (v & 0xff00) pr_err("Bad MSIX cap header: %08x\n", v); @@ -268,10 +255,9 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn, if (where_a == 0x70) { addr = bus->ops->map_bus(bus, devfn, where_a); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } + v = readl(addr); if (v & 0xff00) pr_err("Bad PCIe cap header: %08x\n", v); diff --git a/drivers/pci/controller/pci-thunder-pem.c b/drivers/pci/controller/pci-thunder-pem.c index 0660b9da204f..06a9855cb431 100644 --- a/drivers/pci/controller/pci-thunder-pem.c +++ b/drivers/pci/controller/pci-thunder-pem.c @@ -41,10 +41,8 @@ static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn, struct pci_config_window *cfg = bus->sysdata; struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv; - if (devfn != 0 || where >= 2048) { - *val = ~0; + if (devfn != 0 || where >= 2048) return PCIBIOS_DEVICE_NOT_FOUND; - } /* * 32-bit accesses only. Write the address to the low order -- cgit From 814dccec67ef7319dcaf825da73e8d3bfcdc68f0 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:16 +0530 Subject: PCI: iproc: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/b95defa3db834789a4207df5d6b0216c8b610524.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pcie-iproc.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pcie-iproc.c b/drivers/pci/controller/pcie-iproc.c index 36b9d2c46cfa..b3e75bc61ff1 100644 --- a/drivers/pci/controller/pcie-iproc.c +++ b/drivers/pci/controller/pcie-iproc.c @@ -659,10 +659,8 @@ static int iproc_pci_raw_config_read32(struct iproc_pcie *pcie, void __iomem *addr; addr = iproc_pcie_map_cfg_bus(pcie, 0, devfn, where & ~0x3); - if (!addr) { - *val = ~0; + if (!addr) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = readl(addr); -- cgit From 7e9768539eb32e0fb5eb09f033b33dbd8a15e16d Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:17 +0530 Subject: PCI: mediatek: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/666127469482f9ca177805ff52aeb7bccb26e4c9.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pcie-mediatek.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c index 2f3f974977a3..a19f8ec5d392 100644 --- a/drivers/pci/controller/pcie-mediatek.c +++ b/drivers/pci/controller/pcie-mediatek.c @@ -365,19 +365,12 @@ static int mtk_pcie_config_read(struct pci_bus *bus, unsigned int devfn, { struct mtk_pcie_port *port; u32 bn = bus->number; - int ret; port = mtk_pcie_find_port(bus, devfn); - if (!port) { - *val = ~0; + if (!port) return PCIBIOS_DEVICE_NOT_FOUND; - } - - ret = mtk_pcie_hw_rd_cfg(port, bn, devfn, where, size, val); - if (ret) - *val = ~0; - return ret; + return mtk_pcie_hw_rd_cfg(port, bn, devfn, where, size, val); } static int mtk_pcie_config_write(struct pci_bus *bus, unsigned int devfn, -- cgit From 8ed2196a0ac49dd957ea28105fe826d99f6265af Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:18 +0530 Subject: PCI: exynos: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/765c2f27d85fcee4eb137023dc0a8f864eee9e36.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pci-exynos.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/dwc/pci-exynos.c b/drivers/pci/controller/dwc/pci-exynos.c index c24dab383654..f9526d6de160 100644 --- a/drivers/pci/controller/dwc/pci-exynos.c +++ b/drivers/pci/controller/dwc/pci-exynos.c @@ -216,10 +216,8 @@ static int exynos_pcie_rd_own_conf(struct pci_bus *bus, unsigned int devfn, { struct dw_pcie *pci = to_dw_pcie_from_pp(bus->sysdata); - if (PCI_SLOT(devfn)) { - *val = ~0; + if (PCI_SLOT(devfn)) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = dw_pcie_read_dbi(pci, where, size); return PCIBIOS_SUCCESSFUL; -- cgit From f4a44c1e25822f58e38f26aa85f4aabf46b11072 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:19 +0530 Subject: PCI: histb: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/7da7ea760abc5f85cad6e9b0d3e59eebd93f50d3.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pcie-histb.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/dwc/pcie-histb.c b/drivers/pci/controller/dwc/pcie-histb.c index 86f9d16c50d7..410555dccb6d 100644 --- a/drivers/pci/controller/dwc/pcie-histb.c +++ b/drivers/pci/controller/dwc/pcie-histb.c @@ -127,10 +127,8 @@ static int histb_pcie_rd_own_conf(struct pci_bus *bus, unsigned int devfn, { struct dw_pcie *pci = to_dw_pcie_from_pp(bus->sysdata); - if (PCI_SLOT(devfn)) { - *val = ~0; + if (PCI_SLOT(devfn)) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = dw_pcie_read_dbi(pci, where, size); return PCIBIOS_SUCCESSFUL; -- cgit From 7dcd026fb70fe30308c8be8997799ca92a238e11 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:20 +0530 Subject: PCI: kirin: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/f87e22bc09a471d2cf15ad05dfd6432f57739aed.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pcie-kirin.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/dwc/pcie-kirin.c b/drivers/pci/controller/dwc/pcie-kirin.c index 095afbccf9c1..e6dcac79c02a 100644 --- a/drivers/pci/controller/dwc/pcie-kirin.c +++ b/drivers/pci/controller/dwc/pcie-kirin.c @@ -530,10 +530,8 @@ static int kirin_pcie_rd_own_conf(struct pci_bus *bus, unsigned int devfn, { struct dw_pcie *pci = to_dw_pcie_from_pp(bus->sysdata); - if (PCI_SLOT(devfn)) { - *val = ~0; + if (PCI_SLOT(devfn)) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = dw_pcie_read_dbi(pci, where, size); return PCIBIOS_SUCCESSFUL; -- cgit From 5a50b8b1ea88d75f7088df468ce05778c13f9eb7 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:21 +0530 Subject: PCI: aardvark: Drop error data fabrication when config read fails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/335014f2b44cdf24ed1e37cb7c88f6c5de896cc2.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Reviewed-by: Pali Rohár --- drivers/pci/controller/pci-aardvark.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index c5300d49807a..1de41d2c9b44 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -1026,10 +1026,8 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, u32 reg; int ret; - if (!advk_pcie_valid_device(pcie, bus, devfn)) { - *val = 0xffffffff; + if (!advk_pcie_valid_device(pcie, bus, devfn)) return PCIBIOS_DEVICE_NOT_FOUND; - } if (pci_is_root_bus(bus)) return pci_bridge_emul_conf_read(&pcie->bridge, where, -- cgit From d5da41c0c34a5b253dc1b21b058b3e972afffb87 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:22 +0530 Subject: PCI: mvebu: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/f30264b137b1282ffda34d336e8060bb13d60b98.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pci-mvebu.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index ed13e81cd691..70a96af8cd2f 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -653,20 +653,16 @@ static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, int ret; port = mvebu_pcie_find_port(pcie, bus, devfn); - if (!port) { - *val = 0xffffffff; + if (!port) return PCIBIOS_DEVICE_NOT_FOUND; - } /* Access the emulated PCI-to-PCI bridge */ if (bus->number == 0) return pci_bridge_emul_conf_read(&port->bridge, where, size, val); - if (!mvebu_pcie_link_up(port)) { - *val = 0xffffffff; + if (!mvebu_pcie_link_up(port)) return PCIBIOS_DEVICE_NOT_FOUND; - } /* Access the real PCIe interface */ ret = mvebu_pcie_hw_rd_conf(port, bus, devfn, -- cgit From 5f09342835ab8d8a811a27569170bbf35207bdff Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:23 +0530 Subject: PCI: altera: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/ed5020e5b008b28c33a90c9c1670cef2393d3b7e.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pcie-altera.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pcie-altera.c b/drivers/pci/controller/pcie-altera.c index 2513e9363236..a6bdf9aff833 100644 --- a/drivers/pci/controller/pcie-altera.c +++ b/drivers/pci/controller/pcie-altera.c @@ -510,10 +510,8 @@ static int altera_pcie_cfg_read(struct pci_bus *bus, unsigned int devfn, if (altera_pcie_hide_rc_bar(bus, devfn, where)) return PCIBIOS_BAD_REGISTER_NUMBER; - if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn))) { - *value = 0xffffffff; + if (!altera_pcie_valid_device(pcie, bus, PCI_SLOT(devfn))) return PCIBIOS_DEVICE_NOT_FOUND; - } return _altera_pcie_cfg_read(pcie, bus->number, devfn, where, size, value); -- cgit From 3741f5f4b2a56b232917006663f52c3a084884da Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:24 +0530 Subject: PCI: rcar-host: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/83540eb3ae76a0d28bbe03d69d685a6d549b456b.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Reviewed-by: Geert Uytterhoeven --- drivers/pci/controller/pcie-rcar-host.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index e12c2d8be05a..6bd5619fbbf4 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -159,10 +159,8 @@ static int rcar_pcie_read_conf(struct pci_bus *bus, unsigned int devfn, ret = rcar_pcie_config_access(host, RCAR_PCI_ACCESS_READ, bus, devfn, where, val); - if (ret != PCIBIOS_SUCCESSFUL) { - *val = 0xffffffff; + if (ret != PCIBIOS_SUCCESSFUL) return ret; - } if (size == 1) *val = (*val >> (BITS_PER_BYTE * (where & 3))) & 0xff; -- cgit From ba25d181caaa230107531ed440c3163fc814d4b1 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:25 +0530 Subject: PCI: rockchip-host: Drop error data fabrication when config read fails If config pci_ops.read() methods return failure, the PCI_OP_READ() and PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the data value, so there's no need to set it in the pci_ops.read() methods themselves. Drop the unnecessary data value fabrication when pci_ops.read() fails. Link: https://lore.kernel.org/r/50f9a6fa16521a86cb24d2f27c1f66eb3568cb9a.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pcie-rockchip-host.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pcie-rockchip-host.c b/drivers/pci/controller/pcie-rockchip-host.c index c52316d0bfd2..45a28880f322 100644 --- a/drivers/pci/controller/pcie-rockchip-host.c +++ b/drivers/pci/controller/pcie-rockchip-host.c @@ -221,10 +221,8 @@ static int rockchip_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, { struct rockchip_pcie *rockchip = bus->sysdata; - if (!rockchip_pcie_valid_device(rockchip, bus, PCI_SLOT(devfn))) { - *val = 0xffffffff; + if (!rockchip_pcie_valid_device(rockchip, bus, PCI_SLOT(devfn))) return PCIBIOS_DEVICE_NOT_FOUND; - } if (pci_is_root_bus(bus)) return rockchip_pcie_rd_own_conf(rockchip, where, size, val); -- cgit From fa52b6447ce1cc0157c89dac7762f1693deeb10e Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:26 +0530 Subject: PCI/ERR: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Link: https://lore.kernel.org/r/f4d18d470cb90f9cb52ea155b01528ba2e76e8d6.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 10 +++++----- drivers/pci/probe.c | 10 +++++----- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 3d2fb394986a..bc82699ed105 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1115,7 +1115,7 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state) return -EIO; pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); - if (pmcsr == (u16) ~0) { + if (PCI_POSSIBLE_ERROR(pmcsr)) { pci_err(dev, "can't change power state from %s to %s (config space inaccessible)\n", pci_power_name(dev->current_state), pci_power_name(state)); @@ -1271,16 +1271,16 @@ static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout) * After reset, the device should not silently discard config * requests, but it may still indicate that it needs more time by * responding to them with CRS completions. The Root Port will - * generally synthesize ~0 data to complete the read (except when - * CRS SV is enabled and the read was for the Vendor ID; in that - * case it synthesizes 0x0001 data). + * generally synthesize ~0 (PCI_ERROR_RESPONSE) data to complete + * the read (except when CRS SV is enabled and the read was for the + * Vendor ID; in that case it synthesizes 0x0001 data). * * Wait for the device to return a non-CRS completion. Read the * Command register instead of Vendor ID so we don't have to * contend with the CRS SV value. */ pci_read_config_dword(dev, PCI_COMMAND, &id); - while (id == ~0) { + while (PCI_POSSIBLE_ERROR(id)) { if (delay > timeout) { pci_warn(dev, "not ready %dms after %s; giving up\n", delay - 1, reset_type); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 087d3658f75c..c48fe1ab1961 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -206,14 +206,14 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit * 1 must be clear. */ - if (sz == 0xffffffff) + if (PCI_POSSIBLE_ERROR(sz)) sz = 0; /* * I don't know how l can have all bits set. Copied from old code. * Maybe it fixes a bug on some ancient platform. */ - if (l == 0xffffffff) + if (PCI_POSSIBLE_ERROR(l)) l = 0; if (type == pci_bar_unknown) { @@ -1683,7 +1683,7 @@ static int pci_cfg_space_size_ext(struct pci_dev *dev) if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL) return PCI_CFG_SPACE_SIZE; - if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev)) + if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev)) return PCI_CFG_SPACE_SIZE; return PCI_CFG_SPACE_EXP_SIZE; @@ -2371,8 +2371,8 @@ bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) return false; - /* Some broken boards return 0 or ~0 if a slot is empty: */ - if (*l == 0xffffffff || *l == 0x00000000 || + /* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */ + if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 || *l == 0x0000ffff || *l == 0xffff0000) return false; -- cgit From 242f288e82a34b4c10f87e121b0755056675e55d Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:27 +0530 Subject: PCI: vmd: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Link: https://lore.kernel.org/r/ed01cad87a2e35f3865275b5fb34290817a1ebf8.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Reviewed-by: Jonathan Derrick --- drivers/pci/controller/vmd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index a45e8e59d3d4..515d05605204 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -541,7 +541,7 @@ static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint, int ret; ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock); - if (ret || vmlock == ~0) + if (ret || PCI_POSSIBLE_ERROR(vmlock)) return -ENODEV; if (MB2_SHADOW_EN(vmlock)) { -- cgit From a3b0f10db148f57591bd4559f01246a06a6a7e72 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:28 +0530 Subject: PCI: pciehp: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Compile tested only. Link: https://lore.kernel.org/r/e185b052fbfd530df703a36dd31126cb870eed95.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas Acked-by: Lukas Wunner --- drivers/pci/hotplug/pciehp_hpc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 83a0fa119cae..e94914e50fca 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -89,7 +89,7 @@ static int pcie_poll_cmd(struct controller *ctrl, int timeout) do { pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); - if (slot_status == (u16) ~0) { + if (PCI_POSSIBLE_ERROR(slot_status)) { ctrl_info(ctrl, "%s: no response from device\n", __func__); return 0; @@ -165,7 +165,7 @@ static void pcie_do_write_cmd(struct controller *ctrl, u16 cmd, pcie_wait_cmd(ctrl); pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl); - if (slot_ctrl == (u16) ~0) { + if (PCI_POSSIBLE_ERROR(slot_ctrl)) { ctrl_info(ctrl, "%s: no response from device\n", __func__); goto out; } @@ -236,7 +236,7 @@ int pciehp_check_link_active(struct controller *ctrl) int ret; ret = pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); - if (ret == PCIBIOS_DEVICE_NOT_FOUND || lnk_status == (u16)~0) + if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(lnk_status)) return -ENODEV; ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); @@ -443,7 +443,7 @@ int pciehp_card_present(struct controller *ctrl) int ret; ret = pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); - if (ret == PCIBIOS_DEVICE_NOT_FOUND || slot_status == (u16)~0) + if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(slot_status)) return -ENODEV; return !!(slot_status & PCI_EXP_SLTSTA_PDS); @@ -621,7 +621,7 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) read_status: pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &status); - if (status == (u16) ~0) { + if (PCI_POSSIBLE_ERROR(status)) { ctrl_info(ctrl, "%s: no response from device\n", __func__); if (parent) pm_runtime_put(parent); -- cgit From 0242132da26a928801cbb6ab96daf77e7815e084 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:29 +0530 Subject: PCI/DPC: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Compile tested only. Link: https://lore.kernel.org/r/9b0632f1f183432149f495cf12bdd5a72cc597a4.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/pcie/dpc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index c556e7beafe3..3e9afee02e8d 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -79,7 +79,7 @@ static bool dpc_completed(struct pci_dev *pdev) u16 status; pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_STATUS, &status); - if ((status != 0xffff) && (status & PCI_EXP_DPC_STATUS_TRIGGER)) + if ((!PCI_POSSIBLE_ERROR(status)) && (status & PCI_EXP_DPC_STATUS_TRIGGER)) return false; if (test_bit(PCI_DPC_RECOVERING, &pdev->priv_flags)) @@ -312,7 +312,7 @@ static irqreturn_t dpc_irq(int irq, void *context) pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); - if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT) || status == (u16)(~0)) + if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT) || PCI_POSSIBLE_ERROR(status)) return IRQ_NONE; pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, -- cgit From aa66ea10ba843d35582afaadc0b2f60af063b806 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:30 +0530 Subject: PCI/PME: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Compile tested only. Link: https://lore.kernel.org/r/679ce049bccf10df3ca9ef4918ee2c3235afdaea.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/pcie/pme.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c index 1d0dd77fed3a..ef8ce436ead9 100644 --- a/drivers/pci/pcie/pme.c +++ b/drivers/pci/pcie/pme.c @@ -224,7 +224,7 @@ static void pcie_pme_work_fn(struct work_struct *work) break; pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta); - if (rtsta == (u32) ~0) + if (PCI_POSSIBLE_ERROR(rtsta)) break; if (rtsta & PCI_EXP_RTSTA_PME) { @@ -274,7 +274,7 @@ static irqreturn_t pcie_pme_irq(int irq, void *context) spin_lock_irqsave(&data->lock, flags); pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta); - if (rtsta == (u32) ~0 || !(rtsta & PCI_EXP_RTSTA_PME)) { + if (PCI_POSSIBLE_ERROR(rtsta) || !(rtsta & PCI_EXP_RTSTA_PME)) { spin_unlock_irqrestore(&data->lock, flags); return IRQ_NONE; } -- cgit From a18a025c2fb5fbf2d1d0606ea0d7441ac90e9c39 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:31 +0530 Subject: PCI: cpqphp: Use PCI_POSSIBLE_ERROR() to check config reads When config pci_ops.read() can detect failed PCI transactions, the data returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff). Obviously a successful PCI config read may *also* return that data if a config register happens to contain ~0, so it doesn't definitively indicate an error unless we know the register cannot contain ~0. Use PCI_POSSIBLE_ERROR() to check the response we get when we read data from hardware. This unifies PCI error response checking and makes error checks consistent and easier to find. Link: https://lore.kernel.org/r/b12005c0d57bb9d4c8b486724d078b7bd92f8321.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/hotplug/cpqphp_ctrl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/hotplug/cpqphp_ctrl.c b/drivers/pci/hotplug/cpqphp_ctrl.c index ed7b58eb64d2..93fd2a621822 100644 --- a/drivers/pci/hotplug/cpqphp_ctrl.c +++ b/drivers/pci/hotplug/cpqphp_ctrl.c @@ -2273,7 +2273,7 @@ static u32 configure_new_device(struct controller *ctrl, struct pci_func *func while ((function < max_functions) && (!stop_it)) { pci_bus_read_config_dword(ctrl->pci_bus, PCI_DEVFN(func->device, function), 0x00, &ID); - if (ID == 0xFFFFFFFF) { + if (PCI_POSSIBLE_ERROR(ID)) { function++; } else { /* Setup slot structure. */ @@ -2517,7 +2517,7 @@ static int configure_new_function(struct controller *ctrl, struct pci_func *func pci_bus_read_config_dword(pci_bus, PCI_DEVFN(device, 0), 0x00, &ID); pci_bus->number = func->bus; - if (ID != 0xFFFFFFFF) { /* device present */ + if (!PCI_POSSIBLE_ERROR(ID)) { /* device present */ /* Setup slot structure. */ new_slot = cpqhp_slot_create(hold_bus_node->base); -- cgit From 289e3ea3a506e02f8d4a6a68d6cc0775f4d232c1 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:32 +0530 Subject: PCI: Use PCI_ERROR_RESPONSE to identify config read errors Include PCI_ERROR_RESPONSE along with 0xFFFF and 0xFFFFFFFF in the comment about identifying config read errors. This makes checks for config read errors easier to find. Comment change only. Link: https://lore.kernel.org/r/866e2db544df45af70df7e64659bf02e03998ae3.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/access.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/access.c b/drivers/pci/access.c index a92637627845..0d9f6b21babb 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -412,9 +412,9 @@ int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val) if (pcie_capability_reg_implemented(dev, pos)) { ret = pci_read_config_word(dev, pci_pcie_cap(dev) + pos, val); /* - * Reset *val to 0 if pci_read_config_word() fails, it may - * have been written as 0xFFFF if hardware error happens - * during pci_read_config_word(). + * Reset *val to 0 if pci_read_config_word() fails; it may + * have been written as 0xFFFF (PCI_ERROR_RESPONSE) if the + * config read failed on PCI. */ if (ret) *val = 0; @@ -447,9 +447,9 @@ int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val) if (pcie_capability_reg_implemented(dev, pos)) { ret = pci_read_config_dword(dev, pci_pcie_cap(dev) + pos, val); /* - * Reset *val to 0 if pci_read_config_dword() fails, it may - * have been written as 0xFFFFFFFF if hardware error happens - * during pci_read_config_dword(). + * Reset *val to 0 if pci_read_config_dword() fails; it may + * have been written as 0xFFFFFFFF (PCI_ERROR_RESPONSE) if + * the config read failed on PCI. */ if (ret) *val = 0; -- cgit From 3cfdef7a57a230c68aa981607d402fab428b662d Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:33 +0530 Subject: PCI: keystone: Use PCI_ERROR_RESPONSE to identify config read errors Include PCI_ERROR_RESPONSE along with 0xffffffff in the comment about identifying config read errors. This makes checks for config read errors easier to find. Comment change only. Link: https://lore.kernel.org/r/6ae6b071d92052dc511407513e2a7c0035aff9e7.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pci-keystone.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c index 865258d8c53c..a055ea84b149 100644 --- a/drivers/pci/controller/dwc/pci-keystone.c +++ b/drivers/pci/controller/dwc/pci-keystone.c @@ -747,9 +747,9 @@ err: #ifdef CONFIG_ARM /* - * When a PCI device does not exist during config cycles, keystone host gets a - * bus error instead of returning 0xffffffff. This handler always returns 0 - * for this kind of faults. + * When a PCI device does not exist during config cycles, keystone host + * gets a bus error instead of returning 0xffffffff (PCI_ERROR_RESPONSE). + * This handler always returns 0 for this kind of fault. */ static int ks_pcie_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) -- cgit From 14e04d0d5ed065ae712911589b94edff8e7d406b Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:34 +0530 Subject: PCI: hv: Use PCI_ERROR_RESPONSE to identify config read errors Include PCI_ERROR_RESPONSE along with 0xFFFFFFFF in the comment about identifying config read errors. This makes checks for config read errors easier to find. Comment change only. Link: https://lore.kernel.org/r/12124f41cab7d8aa944de05f85d9567bfe157704.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pci-hyperv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c index 6733cb14e775..1f961d0b5d6b 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -1774,7 +1774,7 @@ static void prepopulate_bars(struct hv_pcibus_device *hbus) * If the memory enable bit is already set, Hyper-V silently ignores * the below BAR updates, and the related PCI device driver can not * work, because reading from the device register(s) always returns - * 0xFFFFFFFF. + * 0xFFFFFFFF (PCI_ERROR_RESPONSE). */ list_for_each_entry(hpdev, &hbus->children, list_entry) { _hv_pcifront_read_config(hpdev, PCI_COMMAND, 2, &command); -- cgit From c78b9a9cbde5fe07ae7c3cc3789e43349db8c437 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:35 +0530 Subject: PCI: xgene: Use PCI_ERROR_RESPONSE to identify config read errors Include PCI_ERROR_RESPONSE along with 0xffffffff in the comment about identifying config read errors. This makes checks for config read errors easier to find. Comment change only. Link: https://lore.kernel.org/r/388b9733bd55394581c447be9f3df42ca2c9759c.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pci-xgene.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c index 56d0d50338c8..bfa506204d73 100644 --- a/drivers/pci/controller/pci-xgene.c +++ b/drivers/pci/controller/pci-xgene.c @@ -171,11 +171,11 @@ static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn, return PCIBIOS_DEVICE_NOT_FOUND; /* - * The v1 controller has a bug in its Configuration Request - * Retry Status (CRS) logic: when CRS Software Visibility is - * enabled and we read the Vendor and Device ID of a non-existent - * device, the controller fabricates return data of 0xFFFF0001 - * ("device exists but is not ready") instead of 0xFFFFFFFF + * The v1 controller has a bug in its Configuration Request Retry + * Status (CRS) logic: when CRS Software Visibility is enabled and + * we read the Vendor and Device ID of a non-existent device, the + * controller fabricates return data of 0xFFFF0001 ("device exists + * but is not ready") instead of 0xFFFFFFFF (PCI_ERROR_RESPONSE) * ("device does not exist"). This causes the PCI core to retry * the read until it times out. Avoid this by not claiming to * support CRS SV. -- cgit