Messages in this thread Patch in this message | | | From | Yash Shah <> | Subject | [PATCH] RISC-V: Add PCIe I/O BAR memory mapping | Date | Thu, 24 Oct 2019 09:14:16 +0000 |
| |
For I/O BARs to work correctly on RISC-V Linux, we need to establish a reserved memory region for them, so that drivers that wish to use I/O BARs can issue reads and writes against a memory region that is mapped to the host PCIe controller's I/O BAR MMIO mapping.
Signed-off-by: Yash Shah <yash.shah@sifive.com> --- arch/riscv/include/asm/io.h | 7 +++++++ arch/riscv/include/asm/pgtable.h | 7 ++++++- 2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h index fc1189a..3ba4d93 100644 --- a/arch/riscv/include/asm/io.h +++ b/arch/riscv/include/asm/io.h @@ -13,6 +13,7 @@ #include <linux/types.h> #include <asm/mmiowb.h> +#include <asm/pgtable.h> extern void __iomem *ioremap(phys_addr_t offset, unsigned long size); @@ -162,6 +163,12 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) #endif /* + * I/O port access constants. + */ +#define IO_SPACE_LIMIT (PCI_IO_SIZE - 1) +#define PCI_IOBASE ((void __iomem *)PCI_IO_START) + +/* * Emulation routines for the port-mapped IO space used by some PCI drivers. * These are defined as being "fully synchronous", but also "not guaranteed to * be fully ordered with respect to other memory and I/O operations". We're diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 7fc5e4a..d78cc74 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -7,6 +7,7 @@ #define _ASM_RISCV_PGTABLE_H #include <linux/mmzone.h> +#include <linux/sizes.h> #include <asm/pgtable-bits.h> @@ -88,6 +89,7 @@ extern pgd_t swapper_pg_dir[]; #define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) #define VMALLOC_END (PAGE_OFFSET - 1) #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) +#define PCI_IO_SIZE SZ_16M /* * Roughly size the vmemmap space to be large enough to fit enough @@ -102,7 +104,10 @@ extern pgd_t swapper_pg_dir[]; #define vmemmap ((struct page *)VMEMMAP_START) -#define FIXADDR_TOP (VMEMMAP_START) +#define PCI_IO_END VMEMMAP_START +#define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE) +#define FIXADDR_TOP PCI_IO_START + #ifdef CONFIG_64BIT #define FIXADDR_SIZE PMD_SIZE #else -- 2.7.4
| |