| Message ID | 20211221141455.30011-5-pali@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: Small improvements for pci-bridge-emul and mvebu | expand |
On Tue, 21 Dec 2021 15:14:48 +0100 Pali Rohár <pali@kernel.org> wrote: > 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. > > Signed-off-by: Pali Rohár <pali@kernel.org> Looks good. As said on PATCH 03/11, perhaps just a snippet of documentation in pci-bridge-emul.h to describe the semantic of the new flag. Thomas
diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c index 432b1bec2e22..033bbeb99176 100644 --- a/drivers/pci/pci-bridge-emul.c +++ b/drivers/pci/pci-bridge-emul.c @@ -378,6 +378,15 @@ 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 88877ebefbac..ab33609c598b 100644 --- a/drivers/pci/pci-bridge-emul.h +++ b/drivers/pci/pci-bridge-emul.h @@ -121,6 +121,7 @@ struct pci_bridge_emul { enum { PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD = BIT(0), + PCI_BRIDGE_EMUL_NO_IO_FORWARD = BIT(1), }; int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
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. Signed-off-by: Pali Rohár <pali@kernel.org> --- drivers/pci/pci-bridge-emul.c | 9 +++++++++ drivers/pci/pci-bridge-emul.h | 1 + 2 files changed, 10 insertions(+)