From bc605cd79edb68131d3be5b00b949aa312277d39 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Thu, 29 Aug 2019 18:44:17 +1000 Subject: [PATCH] powerpc/of/pci: Rewrite pci_parse_of_flags The existing code uses bunch of hardcoded values from the PCI Bus Binding to IEEE Std 1275 spec; and it does so in quite non-obvious way. This defines fields from the cell#0 of the "reg" property of a PCI device and uses them for parsing. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy [mpe: Unsplit some 80/81 char lines, space the code with some newlines] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190829084417.71873-1-aik@ozlabs.ru --- arch/powerpc/kernel/pci_of_scan.c | 66 +++++++++++++++++++++++++------ 1 file changed, 55 insertions(+), 11 deletions(-) diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c index 409c6c1beabf..f91d7e94872e 100644 --- a/arch/powerpc/kernel/pci_of_scan.c +++ b/arch/powerpc/kernel/pci_of_scan.c @@ -34,31 +34,75 @@ static u32 get_int_prop(struct device_node *np, const char *name, u32 def) * pci_parse_of_flags - Parse the flags cell of a device tree PCI address * @addr0: value of 1st cell of a device tree PCI address. * @bridge: Set this flag if the address is from a bridge 'ranges' property + * + * PCI Bus Binding to IEEE Std 1275-1994 + * + * Bit# 33222222 22221111 11111100 00000000 + * 10987654 32109876 54321098 76543210 + * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr + * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh + * phys.lo cell: llllllll llllllll llllllll llllllll + * + * where: + * n is 0 if the address is relocatable, 1 otherwise + * p is 1 if the addressable region is "prefetchable", 0 otherwise + * t is 1 if the address is aliased (for non-relocatable I/O), + * below 1 MB (for Memory),or below 64 KB (for relocatable I/O). + * ss is the space code, denoting the address space: + * 00 denotes Configuration Space + * 01 denotes I/O Space + * 10 denotes 32-bit-address Memory Space + * 11 denotes 64-bit-address Memory Space + * bbbbbbbb is the 8-bit Bus Number + * ddddd is the 5-bit Device Number + * fff is the 3-bit Function Number + * rrrrrrrr is the 8-bit Register Number */ +#define OF_PCI_ADDR0_SPACE(ss) (((ss)&3)<<24) +#define OF_PCI_ADDR0_SPACE_CFG OF_PCI_ADDR0_SPACE(0) +#define OF_PCI_ADDR0_SPACE_IO OF_PCI_ADDR0_SPACE(1) +#define OF_PCI_ADDR0_SPACE_MMIO32 OF_PCI_ADDR0_SPACE(2) +#define OF_PCI_ADDR0_SPACE_MMIO64 OF_PCI_ADDR0_SPACE(3) +#define OF_PCI_ADDR0_SPACE_MASK OF_PCI_ADDR0_SPACE(3) +#define OF_PCI_ADDR0_RELOC (1UL<<31) +#define OF_PCI_ADDR0_PREFETCH (1UL<<30) +#define OF_PCI_ADDR0_ALIAS (1UL<<29) +#define OF_PCI_ADDR0_BUS 0x00FF0000UL +#define OF_PCI_ADDR0_DEV 0x0000F800UL +#define OF_PCI_ADDR0_FN 0x00000700UL +#define OF_PCI_ADDR0_BARREG 0x000000FFUL + unsigned int pci_parse_of_flags(u32 addr0, int bridge) { - unsigned int flags = 0; + unsigned int flags = 0, as = addr0 & OF_PCI_ADDR0_SPACE_MASK; - if (addr0 & 0x02000000) { + if (as == OF_PCI_ADDR0_SPACE_MMIO32 || as == OF_PCI_ADDR0_SPACE_MMIO64) { flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY; - flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64; - if (flags & PCI_BASE_ADDRESS_MEM_TYPE_64) - flags |= IORESOURCE_MEM_64; - flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M; - if (addr0 & 0x40000000) - flags |= IORESOURCE_PREFETCH - | PCI_BASE_ADDRESS_MEM_PREFETCH; + + if (as == OF_PCI_ADDR0_SPACE_MMIO64) + flags |= PCI_BASE_ADDRESS_MEM_TYPE_64 | IORESOURCE_MEM_64; + + if (addr0 & OF_PCI_ADDR0_ALIAS) + flags |= PCI_BASE_ADDRESS_MEM_TYPE_1M; + + if (addr0 & OF_PCI_ADDR0_PREFETCH) + flags |= IORESOURCE_PREFETCH | + PCI_BASE_ADDRESS_MEM_PREFETCH; + /* Note: We don't know whether the ROM has been left enabled * by the firmware or not. We mark it as disabled (ie, we do * not set the IORESOURCE_ROM_ENABLE flag) for now rather than * do a config space read, it will be force-enabled if needed */ - if (!bridge && (addr0 & 0xff) == 0x30) + if (!bridge && (addr0 & OF_PCI_ADDR0_BARREG) == PCI_ROM_ADDRESS) flags |= IORESOURCE_READONLY; - } else if (addr0 & 0x01000000) + + } else if (as == OF_PCI_ADDR0_SPACE_IO) flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO; + if (flags) flags |= IORESOURCE_SIZEALIGN; + return flags; }