powerpc/powernv: Add PIO accessors for Power8 LPC bus

This uses the hooks provided by CONFIG_PPC_INDIRECT_PIO to
implement a set of hooks for IO port access to use the LPC
bus via OPAL calls for the first 64K of IO space
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent b37193b7
......@@ -69,6 +69,14 @@ extern unsigned long pci_dram_offset;
extern resource_size_t isa_mem_base;
/* Boolean set by platform if PIO accesses are suppored while _IO_BASE
* is not set or addresses cannot be translated to MMIO. This is typically
* set when the platform supports "special" PIO accesses via a non memory
* mapped mechanism, and allows things like the early udbg UART code to
* function.
*/
extern bool isa_io_special;
#ifdef CONFIG_PPC32
#if defined(CONFIG_PPC_INDIRECT_PIO) || defined(CONFIG_PPC_INDIRECT_MMIO)
#error CONFIG_PPC_INDIRECT_{PIO,MMIO} are not yet supported on 32 bits
......
......@@ -687,6 +687,8 @@ extern int opal_machine_check(struct pt_regs *regs);
extern void opal_shutdown(void);
extern void opal_lpc_init(void);
#endif /* __ASSEMBLY__ */
#endif /* __OPAL_H */
......@@ -25,6 +25,9 @@
#include <asm/firmware.h>
#include <asm/bug.h>
/* See definition in io.h */
bool isa_io_special;
void _insb(const volatile u8 __iomem *port, void *buf, long count)
{
u8 *tbuf = buf;
......
......@@ -7,6 +7,7 @@ config PPC_POWERNV
select PPC_P7_NAP
select PPC_PCI_CHOICE if EMBEDDED
select EPAPR_BOOT
select PPC_INDIRECT_PIO
default y
config POWERNV_MSI
......
obj-y += setup.o opal-takeover.o opal-wrappers.o opal.o
obj-y += opal-rtc.o opal-nvram.o
obj-y += opal-rtc.o opal-nvram.o opal-lpc.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_PCI) += pci.o pci-p5ioc2.o pci-ioda.o
......
/*
* PowerNV LPC bus handling.
*
* Copyright 2013 IBM Corp.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/bug.h>
#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/xics.h>
#include <asm/opal.h>
static int opal_lpc_chip_id = -1;
static u8 opal_lpc_inb(unsigned long port)
{
int64_t rc;
uint32_t data;
if (opal_lpc_chip_id < 0 || port > 0xffff)
return 0xff;
rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 1);
return rc ? 0xff : data;
}
static __le16 __opal_lpc_inw(unsigned long port)
{
int64_t rc;
uint32_t data;
if (opal_lpc_chip_id < 0 || port > 0xfffe)
return 0xffff;
if (port & 1)
return (__le16)opal_lpc_inb(port) << 8 | opal_lpc_inb(port + 1);
rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 2);
return rc ? 0xffff : data;
}
static u16 opal_lpc_inw(unsigned long port)
{
return le16_to_cpu(__opal_lpc_inw(port));
}
static __le32 __opal_lpc_inl(unsigned long port)
{
int64_t rc;
uint32_t data;
if (opal_lpc_chip_id < 0 || port > 0xfffc)
return 0xffffffff;
if (port & 3)
return (__le32)opal_lpc_inb(port ) << 24 |
(__le32)opal_lpc_inb(port + 1) << 16 |
(__le32)opal_lpc_inb(port + 2) << 8 |
opal_lpc_inb(port + 3);
rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 4);
return rc ? 0xffffffff : data;
}
static u32 opal_lpc_inl(unsigned long port)
{
return le32_to_cpu(__opal_lpc_inl(port));
}
static void opal_lpc_outb(u8 val, unsigned long port)
{
if (opal_lpc_chip_id < 0 || port > 0xffff)
return;
opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 1);
}
static void __opal_lpc_outw(__le16 val, unsigned long port)
{
if (opal_lpc_chip_id < 0 || port > 0xfffe)
return;
if (port & 1) {
opal_lpc_outb(val >> 8, port);
opal_lpc_outb(val , port + 1);
return;
}
opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 2);
}
static void opal_lpc_outw(u16 val, unsigned long port)
{
__opal_lpc_outw(cpu_to_le16(val), port);
}
static void __opal_lpc_outl(__le32 val, unsigned long port)
{
if (opal_lpc_chip_id < 0 || port > 0xfffc)
return;
if (port & 3) {
opal_lpc_outb(val >> 24, port);
opal_lpc_outb(val >> 16, port + 1);
opal_lpc_outb(val >> 8, port + 2);
opal_lpc_outb(val , port + 3);
return;
}
opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 4);
}
static void opal_lpc_outl(u32 val, unsigned long port)
{
__opal_lpc_outl(cpu_to_le32(val), port);
}
static void opal_lpc_insb(unsigned long p, void *b, unsigned long c)
{
u8 *ptr = b;
while(c--)
*(ptr++) = opal_lpc_inb(p);
}
static void opal_lpc_insw(unsigned long p, void *b, unsigned long c)
{
__le16 *ptr = b;
while(c--)
*(ptr++) = __opal_lpc_inw(p);
}
static void opal_lpc_insl(unsigned long p, void *b, unsigned long c)
{
__le32 *ptr = b;
while(c--)
*(ptr++) = __opal_lpc_inl(p);
}
static void opal_lpc_outsb(unsigned long p, const void *b, unsigned long c)
{
const u8 *ptr = b;
while(c--)
opal_lpc_outb(*(ptr++), p);
}
static void opal_lpc_outsw(unsigned long p, const void *b, unsigned long c)
{
const __le16 *ptr = b;
while(c--)
__opal_lpc_outw(*(ptr++), p);
}
static void opal_lpc_outsl(unsigned long p, const void *b, unsigned long c)
{
const __le32 *ptr = b;
while(c--)
__opal_lpc_outl(*(ptr++), p);
}
static const struct ppc_pci_io opal_lpc_io = {
.inb = opal_lpc_inb,
.inw = opal_lpc_inw,
.inl = opal_lpc_inl,
.outb = opal_lpc_outb,
.outw = opal_lpc_outw,
.outl = opal_lpc_outl,
.insb = opal_lpc_insb,
.insw = opal_lpc_insw,
.insl = opal_lpc_insl,
.outsb = opal_lpc_outsb,
.outsw = opal_lpc_outsw,
.outsl = opal_lpc_outsl,
};
void opal_lpc_init(void)
{
struct device_node *np;
/*
* Look for a Power8 LPC bus tagged as "primary",
* we currently support only one though the OPAL APIs
* support any number.
*/
for_each_compatible_node(np, NULL, "ibm,power8-lpc") {
if (!of_device_is_available(np))
continue;
if (!of_get_property(np, "primary", NULL))
continue;
opal_lpc_chip_id = of_get_ibm_chip_id(np);
break;
}
if (opal_lpc_chip_id < 0)
return;
/* Setup special IO ops */
ppc_pci_io = opal_lpc_io;
isa_io_special = true;
pr_info("OPAL: Power8 LPC bus found, chip ID %d\n", opal_lpc_chip_id);
}
......@@ -15,4 +15,6 @@ static inline void pnv_pci_init(void) { }
static inline void pnv_pci_shutdown(void) { }
#endif
extern void pnv_lpc_init(void);
#endif /* _POWERNV_H */
......@@ -54,6 +54,12 @@ static void __init pnv_setup_arch(void)
static void __init pnv_init_early(void)
{
/*
* Initialize the LPC bus now so that legacy serial
* ports can be found on it
*/
opal_lpc_init();
#ifdef CONFIG_HVC_OPAL
if (firmware_has_feature(FW_FEATURE_OPAL))
hvc_opal_init_early();
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment