linux-stable/arch/powerpc/kernel/io-workarounds.c
Christophe Leroy 14b4d97669 powerpc/mm: rework io-workaround invocation.
ppc_md.ioremap() is only used for I/O workaround on CELL platform,
so indirect function call can be avoided.

This patch reworks the io-workaround and ioremap() functions to
use the global 'io_workaround_inited' flag for the activation
of io-workaround.

When CONFIG_PPC_IO_WORKAROUNDS or CONFIG_PPC_INDIRECT_MMIO are not
selected, the I/O workaround ioremap() voids and the global flag is
not used.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5fa3ef069fbd0f152512afaae19e7a60161454cf.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:34 +10:00

207 lines
4.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Support PCI IO workaround
*
* Copyright (C) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>
* IBM, Corp.
* (C) Copyright 2007-2008 TOSHIBA CORPORATION
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/sched/mm.h> /* for init_mm */
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/pgtable.h>
#include <asm/ppc-pci.h>
#include <asm/io-workarounds.h>
#include <asm/pte-walk.h>
#define IOWA_MAX_BUS 8
static struct iowa_bus iowa_busses[IOWA_MAX_BUS];
static unsigned int iowa_bus_count;
static struct iowa_bus *iowa_pci_find(unsigned long vaddr, unsigned long paddr)
{
int i, j;
struct resource *res;
unsigned long vstart, vend;
for (i = 0; i < iowa_bus_count; i++) {
struct iowa_bus *bus = &iowa_busses[i];
struct pci_controller *phb = bus->phb;
if (vaddr) {
vstart = (unsigned long)phb->io_base_virt;
vend = vstart + phb->pci_io_size - 1;
if ((vaddr >= vstart) && (vaddr <= vend))
return bus;
}
if (paddr)
for (j = 0; j < 3; j++) {
res = &phb->mem_resources[j];
if (paddr >= res->start && paddr <= res->end)
return bus;
}
}
return NULL;
}
#ifdef CONFIG_PPC_INDIRECT_MMIO
struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
{
unsigned hugepage_shift;
struct iowa_bus *bus;
int token;
token = PCI_GET_ADDR_TOKEN(addr);
if (token && token <= iowa_bus_count)
bus = &iowa_busses[token - 1];
else {
unsigned long vaddr, paddr;
pte_t *ptep;
vaddr = (unsigned long)PCI_FIX_ADDR(addr);
if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END)
return NULL;
/*
* We won't find huge pages here (iomem). Also can't hit
* a page table free due to init_mm
*/
ptep = find_init_mm_pte(vaddr, &hugepage_shift);
if (ptep == NULL)
paddr = 0;
else {
WARN_ON(hugepage_shift);
paddr = pte_pfn(*ptep) << PAGE_SHIFT;
}
bus = iowa_pci_find(vaddr, paddr);
if (bus == NULL)
return NULL;
}
return bus;
}
#else /* CONFIG_PPC_INDIRECT_MMIO */
struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
{
return NULL;
}
#endif /* !CONFIG_PPC_INDIRECT_MMIO */
#ifdef CONFIG_PPC_INDIRECT_PIO
struct iowa_bus *iowa_pio_find_bus(unsigned long port)
{
unsigned long vaddr = (unsigned long)pci_io_base + port;
return iowa_pci_find(vaddr, 0);
}
#else
struct iowa_bus *iowa_pio_find_bus(unsigned long port)
{
return NULL;
}
#endif
#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \
static ret iowa_##name at \
{ \
struct iowa_bus *bus; \
bus = iowa_##space##_find_bus(aa); \
if (bus && bus->ops && bus->ops->name) \
return bus->ops->name al; \
return __do_##name al; \
}
#define DEF_PCI_AC_NORET(name, at, al, space, aa) \
static void iowa_##name at \
{ \
struct iowa_bus *bus; \
bus = iowa_##space##_find_bus(aa); \
if (bus && bus->ops && bus->ops->name) { \
bus->ops->name al; \
return; \
} \
__do_##name al; \
}
#include <asm/io-defs.h>
#undef DEF_PCI_AC_RET
#undef DEF_PCI_AC_NORET
static const struct ppc_pci_io iowa_pci_io = {
#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name,
#define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name,
#include <asm/io-defs.h>
#undef DEF_PCI_AC_RET
#undef DEF_PCI_AC_NORET
};
#ifdef CONFIG_PPC_INDIRECT_MMIO
void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size,
pgprot_t prot, void *caller)
{
struct iowa_bus *bus;
void __iomem *res = __ioremap_caller(addr, size, prot, caller);
int busno;
bus = iowa_pci_find(0, (unsigned long)addr);
if (bus != NULL) {
busno = bus - iowa_busses;
PCI_SET_ADDR_TOKEN(res, busno + 1);
}
return res;
}
#endif /* !CONFIG_PPC_INDIRECT_MMIO */
bool io_workaround_inited;
/* Enable IO workaround */
static void io_workaround_init(void)
{
if (io_workaround_inited)
return;
ppc_pci_io = iowa_pci_io;
io_workaround_inited = true;
}
/* Register new bus to support workaround */
void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops,
int (*initfunc)(struct iowa_bus *, void *), void *data)
{
struct iowa_bus *bus;
struct device_node *np = phb->dn;
io_workaround_init();
if (iowa_bus_count >= IOWA_MAX_BUS) {
pr_err("IOWA:Too many pci bridges, "
"workarounds disabled for %pOF\n", np);
return;
}
bus = &iowa_busses[iowa_bus_count];
bus->phb = phb;
bus->ops = ops;
bus->private = data;
if (initfunc)
if ((*initfunc)(bus, data))
return;
iowa_bus_count++;
pr_debug("IOWA:[%d]Add bus, %pOF.\n", iowa_bus_count-1, np);
}