linux/arch/x86/pci/ce4100.c
Thomas Gleixner bb290fda87 x86/PCI/ce4100: Properly lock accessor functions
x86 wants to get rid of the global pci_lock protecting the config space
accessors so ECAM mode can operate completely lockless, but the CE4100 PCI
code relies on that to protect the simulation registers.

Restructure the code so it uses the x86 specific pci_config_lock to
serialize the inner workings of the CE4100 PCI magic. That allows to remove
the global locking via pci_lock later.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <helgaas@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/20170316215057.126873574@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-28 22:32:55 +02:00

341 lines
10 KiB
C

/*
* GPL LICENSE SUMMARY
*
* Copyright(c) 2010 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
* The full GNU General Public License is included in this distribution
* in the file called LICENSE.GPL.
*
* Contact Information:
* Intel Corporation
* 2200 Mission College Blvd.
* Santa Clara, CA 97052
*
* This provides access methods for PCI registers that mis-behave on
* the CE4100. Each register can be assigned a private init, read and
* write routine. The exception to this is the bridge device. The
* bridge device is the only device on bus zero (0) that requires any
* fixup so it is a special case ATM
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <asm/ce4100.h>
#include <asm/pci_x86.h>
struct sim_reg {
u32 value;
u32 mask;
};
struct sim_dev_reg {
int dev_func;
int reg;
void (*init)(struct sim_dev_reg *reg);
void (*read)(struct sim_dev_reg *reg, u32 *value);
void (*write)(struct sim_dev_reg *reg, u32 value);
struct sim_reg sim_reg;
};
struct sim_reg_op {
void (*init)(struct sim_dev_reg *reg);
void (*read)(struct sim_dev_reg *reg, u32 value);
void (*write)(struct sim_dev_reg *reg, u32 value);
};
#define MB (1024 * 1024)
#define KB (1024)
#define SIZE_TO_MASK(size) (~(size - 1))
#define DEFINE_REG(device, func, offset, size, init_op, read_op, write_op)\
{ PCI_DEVFN(device, func), offset, init_op, read_op, write_op,\
{0, SIZE_TO_MASK(size)} },
/*
* All read/write functions are called with pci_config_lock held.
*/
static void reg_init(struct sim_dev_reg *reg)
{
pci_direct_conf1.read(0, 1, reg->dev_func, reg->reg, 4,
&reg->sim_reg.value);
}
static void reg_read(struct sim_dev_reg *reg, u32 *value)
{
*value = reg->sim_reg.value;
}
static void reg_write(struct sim_dev_reg *reg, u32 value)
{
reg->sim_reg.value = (value & reg->sim_reg.mask) |
(reg->sim_reg.value & ~reg->sim_reg.mask);
}
static void sata_reg_init(struct sim_dev_reg *reg)
{
pci_direct_conf1.read(0, 1, PCI_DEVFN(14, 0), 0x10, 4,
&reg->sim_reg.value);
reg->sim_reg.value += 0x400;
}
static void ehci_reg_read(struct sim_dev_reg *reg, u32 *value)
{
reg_read(reg, value);
if (*value != reg->sim_reg.mask)
*value |= 0x100;
}
void sata_revid_init(struct sim_dev_reg *reg)
{
reg->sim_reg.value = 0x01060100;
reg->sim_reg.mask = 0;
}
static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
{
reg_read(reg, value);
}
static void reg_noirq_read(struct sim_dev_reg *reg, u32 *value)
{
/* force interrupt pin value to 0 */
*value = reg->sim_reg.value & 0xfff00ff;
}
static struct sim_dev_reg bus1_fixups[] = {
DEFINE_REG(2, 0, 0x10, (16*MB), reg_init, reg_read, reg_write)
DEFINE_REG(2, 0, 0x14, (256), reg_init, reg_read, reg_write)
DEFINE_REG(2, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(3, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(4, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
DEFINE_REG(4, 1, 0x10, (128*KB), reg_init, reg_read, reg_write)
DEFINE_REG(6, 0, 0x10, (512*KB), reg_init, reg_read, reg_write)
DEFINE_REG(6, 1, 0x10, (512*KB), reg_init, reg_read, reg_write)
DEFINE_REG(6, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(8, 0, 0x10, (1*MB), reg_init, reg_read, reg_write)
DEFINE_REG(8, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(8, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(9, 0, 0x10 , (1*MB), reg_init, reg_read, reg_write)
DEFINE_REG(9, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(10, 0, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(10, 0, 0x14, (256*MB), reg_init, reg_read, reg_write)
DEFINE_REG(11, 0, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 0, 0x14, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 1, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 2, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 2, 0x14, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 2, 0x18, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 3, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 3, 0x14, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 4, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 5, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(11, 6, 0x10, (256), reg_init, reg_read, reg_write)
DEFINE_REG(11, 7, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(11, 7, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
DEFINE_REG(12, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
DEFINE_REG(12, 0, 0x14, (256), reg_init, reg_read, reg_write)
DEFINE_REG(12, 1, 0x10, (1024), reg_init, reg_read, reg_write)
DEFINE_REG(13, 0, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
DEFINE_REG(13, 1, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
DEFINE_REG(14, 0, 0x8, 0, sata_revid_init, sata_revid_read, 0)
DEFINE_REG(14, 0, 0x10, 0, reg_init, reg_read, reg_write)
DEFINE_REG(14, 0, 0x14, 0, reg_init, reg_read, reg_write)
DEFINE_REG(14, 0, 0x18, 0, reg_init, reg_read, reg_write)
DEFINE_REG(14, 0, 0x1C, 0, reg_init, reg_read, reg_write)
DEFINE_REG(14, 0, 0x20, 0, reg_init, reg_read, reg_write)
DEFINE_REG(14, 0, 0x24, (0x200), sata_reg_init, reg_read, reg_write)
DEFINE_REG(15, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(15, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(16, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
DEFINE_REG(16, 0, 0x14, (64*MB), reg_init, reg_read, reg_write)
DEFINE_REG(16, 0, 0x18, (64*MB), reg_init, reg_read, reg_write)
DEFINE_REG(16, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
DEFINE_REG(17, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
DEFINE_REG(18, 0, 0x10, (1*KB), reg_init, reg_read, reg_write)
DEFINE_REG(18, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
};
static void __init init_sim_regs(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
if (bus1_fixups[i].init)
bus1_fixups[i].init(&bus1_fixups[i]);
}
}
static inline void extract_bytes(u32 *value, int reg, int len)
{
uint32_t mask;
*value >>= ((reg & 3) * 8);
mask = 0xFFFFFFFF >> ((4 - len) * 8);
*value &= mask;
}
int bridge_read(unsigned int devfn, int reg, int len, u32 *value)
{
u32 av_bridge_base, av_bridge_limit;
int retval = 0;
switch (reg) {
/* Make BARs appear to not request any memory. */
case PCI_BASE_ADDRESS_0:
case PCI_BASE_ADDRESS_0 + 1:
case PCI_BASE_ADDRESS_0 + 2:
case PCI_BASE_ADDRESS_0 + 3:
*value = 0;
break;
/* Since subordinate bus number register is hardwired
* to zero and read only, so do the simulation.
*/
case PCI_PRIMARY_BUS:
if (len == 4)
*value = 0x00010100;
break;
case PCI_SUBORDINATE_BUS:
*value = 1;
break;
case PCI_MEMORY_BASE:
case PCI_MEMORY_LIMIT:
/* Get the A/V bridge base address. */
pci_direct_conf1.read(0, 0, devfn,
PCI_BASE_ADDRESS_0, 4, &av_bridge_base);
av_bridge_limit = av_bridge_base + (512*MB - 1);
av_bridge_limit >>= 16;
av_bridge_limit &= 0xFFF0;
av_bridge_base >>= 16;
av_bridge_base &= 0xFFF0;
if (reg == PCI_MEMORY_LIMIT)
*value = av_bridge_limit;
else if (len == 2)
*value = av_bridge_base;
else
*value = (av_bridge_limit << 16) | av_bridge_base;
break;
/* Make prefetchable memory limit smaller than prefetchable
* memory base, so not claim prefetchable memory space.
*/
case PCI_PREF_MEMORY_BASE:
*value = 0xFFF0;
break;
case PCI_PREF_MEMORY_LIMIT:
*value = 0x0;
break;
/* Make IO limit smaller than IO base, so not claim IO space. */
case PCI_IO_BASE:
*value = 0xF0;
break;
case PCI_IO_LIMIT:
*value = 0;
break;
default:
retval = 1;
}
return retval;
}
static int ce4100_bus1_read(unsigned int devfn, int reg, int len, u32 *value)
{
unsigned long flags;
int i;
for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
if (bus1_fixups[i].dev_func == devfn &&
bus1_fixups[i].reg == (reg & ~3) &&
bus1_fixups[i].read) {
raw_spin_lock_irqsave(&pci_config_lock, flags);
bus1_fixups[i].read(&(bus1_fixups[i]), value);
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
extract_bytes(value, reg, len);
return 0;
}
}
return -1;
}
static int ce4100_conf_read(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *value)
{
WARN_ON(seg);
if (bus == 1 && !ce4100_bus1_read(devfn, reg, len, value))
return 0;
if (bus == 0 && (PCI_DEVFN(1, 0) == devfn) &&
!bridge_read(devfn, reg, len, value))
return 0;
return pci_direct_conf1.read(seg, bus, devfn, reg, len, value);
}
static int ce4100_bus1_write(unsigned int devfn, int reg, int len, u32 value)
{
unsigned long flags;
int i;
for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
if (bus1_fixups[i].dev_func == devfn &&
bus1_fixups[i].reg == (reg & ~3) &&
bus1_fixups[i].write) {
raw_spin_lock_irqsave(&pci_config_lock, flags);
bus1_fixups[i].write(&(bus1_fixups[i]), value);
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
return 0;
}
}
return -1;
}
static int ce4100_conf_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
{
WARN_ON(seg);
if (bus == 1 && !ce4100_bus1_write(devfn, reg, len, value))
return 0;
/* Discard writes to A/V bridge BAR. */
if (bus == 0 && PCI_DEVFN(1, 0) == devfn &&
((reg & ~3) == PCI_BASE_ADDRESS_0))
return 0;
return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);
}
static const struct pci_raw_ops ce4100_pci_conf = {
.read = ce4100_conf_read,
.write = ce4100_conf_write,
};
int __init ce4100_pci_init(void)
{
init_sim_regs();
raw_pci_ops = &ce4100_pci_conf;
/* Indicate caller that it should invoke pci_legacy_init() */
return 1;
}