diff options
Diffstat (limited to 'target/linux/generic/backport-5.15/850-v5.17-0001-PCI-pci-bridge-emul-Add-description-for-class_revisi.patch')
| -rw-r--r-- | target/linux/generic/backport-5.15/850-v5.17-0001-PCI-pci-bridge-emul-Add-description-for-class_revisi.patch | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.15/850-v5.17-0001-PCI-pci-bridge-emul-Add-description-for-class_revisi.patch b/target/linux/generic/backport-5.15/850-v5.17-0001-PCI-pci-bridge-emul-Add-description-for-class_revisi.patch new file mode 100644 index 0000000000..19a4be2a9d --- /dev/null +++ b/target/linux/generic/backport-5.15/850-v5.17-0001-PCI-pci-bridge-emul-Add-description-for-class_revisi.patch @@ -0,0 +1,44 @@ +From 9319230ac147067652b58fe849ffe0ceec098665 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org> +Date: Tue, 30 Nov 2021 18:29:03 +0100 +Subject: [PATCH] PCI: pci-bridge-emul: Add description for class_revision + field +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +The current assignment to the class_revision member + + class_revision |= cpu_to_le32(PCI_CLASS_BRIDGE_PCI << 16); + +can make the reader think that class is at high 16 bits of the member and +revision at low 16 bits. + +In reality, class is at high 24 bits, but the class for PCI Bridge Normal +Decode is PCI_CLASS_BRIDGE_PCI << 8. + +Change the assignment and add a comment to make this clearer. + +Link: https://lore.kernel.org/r/20211130172913.9727-2-kabel@kernel.org +Signed-off-by: Pali Rohár <pali@kernel.org> +Signed-off-by: Marek Behún <kabel@kernel.org> +Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> +--- + drivers/pci/pci-bridge-emul.c | 6 +++++- + 1 file changed, 5 insertions(+), 1 deletion(-) + +--- a/drivers/pci/pci-bridge-emul.c ++++ b/drivers/pci/pci-bridge-emul.c +@@ -284,7 +284,11 @@ int pci_bridge_emul_init(struct pci_brid + { + BUILD_BUG_ON(sizeof(bridge->conf) != PCI_BRIDGE_CONF_END); + +- bridge->conf.class_revision |= cpu_to_le32(PCI_CLASS_BRIDGE_PCI << 16); ++ /* ++ * class_revision: Class is high 24 bits and revision is low 8 bit of this member, ++ * while class for PCI Bridge Normal Decode has the 24-bit value: PCI_CLASS_BRIDGE_PCI << 8 ++ */ ++ bridge->conf.class_revision |= cpu_to_le32((PCI_CLASS_BRIDGE_PCI << 8) << 8); + bridge->conf.header_type = PCI_HEADER_TYPE_BRIDGE; + bridge->conf.cache_line_size = 0x10; + bridge->conf.status = cpu_to_le16(PCI_STATUS_CAP_LIST); |