RISC-V: Add PCIe I/O BAR memory mapping

For legacy I/O BARs (non-MMIO 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 the legacy I/O BARs can issue reads and writes against
a memory region that is mapped to the host PCIe controller's I/O BAR
mapping.

Signed-off-by: Yash Shah <yash.shah@sifive.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
This commit is contained in:
Yash Shah 2019-10-25 08:30:03 +00:00 committed by Paul Walmsley
parent f307307992
commit 00a5bf3a8c
2 changed files with 13 additions and 1 deletions

View File

@ -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);
@ -161,6 +162,12 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
#define writeq(v,c) ({ __io_bw(); writeq_cpu((v),(c)); __io_aw(); })
#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

View File

@ -7,6 +7,7 @@
#define _ASM_RISCV_PGTABLE_H
#include <linux/mmzone.h>
#include <linux/sizes.h>
#include <asm/pgtable-bits.h>
@ -86,6 +87,7 @@ 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
@ -100,7 +102,10 @@ 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