From 05241c13655c43116ea7322a6edffc47d7218550 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= Date: Tue, 4 Jan 2022 16:35:22 +0100 Subject: [PATCH] PCI: pci-bridge-emul: Add support for new flag PCI_BRIDGE_EMUL_NO_IO_FORWARD MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Like PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD, this new flag specifies that emulated PCI bridge does not support forwarding of IO requests in given range between primary and secondary buses. This flag should be used as argument for pci_bridge_emul_init() for hardware setup without IO support. Setting this flag cause that IO base and limit registers are read-only. Link: https://lore.kernel.org/r/20220104153529.31647-5-pali@kernel.org Signed-off-by: Pali Rohár Signed-off-by: Lorenzo Pieralisi Reviewed-by: Rob Herring --- drivers/pci/pci-bridge-emul.c | 9 +++++++++ drivers/pci/pci-bridge-emul.h | 6 ++++++ 2 files changed, 15 insertions(+) diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c index ceacba03e714..a16f9e30099e 100644 --- a/drivers/pci/pci-bridge-emul.c +++ b/drivers/pci/pci-bridge-emul.c @@ -382,6 +382,15 @@ int pci_bridge_emul_init(struct pci_bridge_emul *bridge, bridge->pci_regs_behavior[PCI_PREF_MEMORY_BASE / 4].rw = 0; } + if (flags & PCI_BRIDGE_EMUL_NO_IO_FORWARD) { + bridge->pci_regs_behavior[PCI_COMMAND / 4].ro |= PCI_COMMAND_IO; + bridge->pci_regs_behavior[PCI_COMMAND / 4].rw &= ~PCI_COMMAND_IO; + bridge->pci_regs_behavior[PCI_IO_BASE / 4].ro |= GENMASK(15, 0); + bridge->pci_regs_behavior[PCI_IO_BASE / 4].rw &= ~GENMASK(15, 0); + bridge->pci_regs_behavior[PCI_IO_BASE_UPPER16 / 4].ro = ~0; + bridge->pci_regs_behavior[PCI_IO_BASE_UPPER16 / 4].rw = 0; + } + return 0; } EXPORT_SYMBOL_GPL(pci_bridge_emul_init); diff --git a/drivers/pci/pci-bridge-emul.h b/drivers/pci/pci-bridge-emul.h index 087b5fa01bcf..4953274cac18 100644 --- a/drivers/pci/pci-bridge-emul.h +++ b/drivers/pci/pci-bridge-emul.h @@ -125,6 +125,12 @@ enum { * requests between primary and secondary buses. */ PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD = BIT(0), + + /* + * PCI bridge does not support forwarding of IO requests between + * primary and secondary buses. + */ + PCI_BRIDGE_EMUL_NO_IO_FORWARD = BIT(1), }; int pci_bridge_emul_init(struct pci_bridge_emul *bridge,