/*
* BRIEF MODULE DESCRIPTION
* Alchemy/AMD Au1xx0 PCI support.
*
* Copyright 2001-2003, 2007-2008 MontaVista Software Inc.
* Author: MontaVista Software, Inc. <source@mvista.com>
*
* Support for all devices (greater than 16) added by David Gathright.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <asm/mach-au1x00/au1000.h>
#undef DEBUG
#ifdef DEBUG
#define DBG(x...) printk(KERN_DEBUG x)
#else
#define DBG(x...)
#endif
#define PCI_ACCESS_READ 0
#define PCI_ACCESS_WRITE 1
int (*board_pci_idsel)(unsigned int devsel, int assert);
void mod_wired_entry(int entry, unsigned long entrylo0,
unsigned long entrylo1, unsigned long entryhi,
unsigned long pagemask)
{
unsigned long old_pagemask;
unsigned long old_ctx;
/* Save old context and create impossible VPN2 value */
old_ctx = read_c0_entryhi() & 0xff;
old_pagemask = read_c0_pagemask();
write_c0_index(entry);
write_c0_pagemask(pagemask);
write_c0_entryhi(entryhi);
write_c0_entrylo0(entrylo0);
write_c0_entrylo1(entrylo1);
tlb_write_indexed();
write_c0_entryhi(old_ctx);
write_c0_pagemask(old_pagemask);
}
static struct vm_struct *pci_cfg_vm;
static int pci_cfg_wired_entry;
static unsigned long last_entryLo0, last_entryLo1;
/*
* We can't ioremap the entire pci config space because it's too large.
* Nor can we call ioremap dynamically because some device drivers use
* the PCI config routines from within interrupt handlers and that
* becomes a problem in get_vm_area(). We use one wired TLB to handle
* all config accesses for all busses.
*/
void __init au1x_pci_cfg_init(void)
{
/* Reserve a wired entry for PCI config accesses */
pci_cfg_vm = get_vm_area(0x2000, VM_IOREMAP);
if (!pci_cfg_vm)
panic(KERN_ERR "PCI unable to get vm area\n");
pci_cfg_wired_entry = read_c0_wired();
add_wired_entry(0, 0, (unsigned long)pci_cfg_vm->addr, PM_4K);
last_entryLo0 = last_entryLo1 = 0xffffffff;
}
static int config_access(unsigned char access_type, struct pci_bus *bus,
unsigned int dev_fn, unsigned char where, u32 *data)
{
#if defined(CONFIG_SOC_AU1500) || defined(CONFIG_SOC_AU1550)
unsigned int device = PCI_SLOT(dev_fn);
unsigned int function = PCI_FUNC(dev_fn);
unsigned long offset, status;
unsigned long cfg_base;
unsigned long flags;
int error = PCIBIOS_SUCCESSFUL;
unsigned long entryLo0, entryLo1;
if (device > 19) {
*data = 0xffffffff;
return -1;
}
local_irq_save(flags);
au_writel(((0x2000 << 16) | (au_readl(Au1500_PCI_STATCMD) & 0xffff)),
Au1500_PCI_STATCMD);
au_sync_udelay(1);
/*
* Allow board vendors to implement their own off-chip IDSEL.
* If it doesn't succeed, may as well bail out at this point.
*/
if (board_pci_idsel && board_pci_idsel(device, 1) == 0) {
*data = 0xffffffff;
local_irq_restore(flags);
return -1;
}
/* Setup the config window */
if (bus->number == 0)
cfg_base = (1 << device) << 11;
else
cfg_base = 0x80000000 | (bus->number << 16) | (device << 11);
/* Setup the lower bits of the 36-bit address */
offset = (function << 8) | (where & ~0x3);
/* Pick up any address that falls below the page mask */
offset |= cfg_base & ~PAGE_MASK;
/* Page boundary */
cfg_base = cfg_base & PAGE_MASK;
/*
* To improve performance, if the current device is the same as
* the last device accessed, we don't touch the TLB.
*/
entryLo0 = (6 << 26) | (cfg_base >> 6) | (2 << 3) | 7;
entryLo1 = (6 << 26) | (cfg_base >> 6) | (0x1000 >> 6) | (2 << 3) | 7;
if ((entryLo0 != last_entryLo0) || (entryLo1 != last_entryLo1)) {
mod_wired_entry(pci_cfg_wired_entry, entryLo0, entryLo1,
(unsigned long)pci_cfg_vm->addr, PM_4K);
last_entryLo0 = entryLo0;
last_entryLo1 = entryLo1;
}
if (access_type == PCI_ACCESS_WRITE)
au_writel(*data, (int)(pci_cfg_vm->addr + offset));
else
*data = au_readl((int)(pci_cfg_vm->addr + offset));
au_sync_udelay(2);
DBG("cfg_access %d bus->number %u dev %u at %x *data %x conf %lx\n",
access_type, bus->number, device, where, *data, offset);
/* Check master abort */
status = au_readl(Au1500_PCI_STATCMD);
if (status & (1 << 29)) {
*data = 0xffffffff;
error = -1;
DBG("Au1x Master Abort\n");
} else if ((status >> 28) & 0xf) {
DBG("PCI ERR detected: device %u, status %lx\n",
device, (status >> 28) & 0xf);
/* Clear errors */
au_writel(status & 0xf000ffff, Au1500_PCI_STATCMD);
*data = 0xffffffff;
error = -1;
}
/* Take away the IDSEL. */
if (board_pci_idsel)
(void)board_pci_idsel(device, 0);
local_irq_restore(flags);
return error;
#endif
}
static int read_config_byte(struct pci_bus *bus, unsigned int devfn,
int where, u8 *val)
{
u32 data;
int ret;
ret = config_access(PCI_ACCESS_READ, bus, devfn, where, &data);
if (where & 1)
data >>= 8;
if (where & 2)
data >>= 16;
*val = data & 0xff;
return ret;
}
static int read_config_word(struct pci_bus *bus, unsigned int devfn,
int where, u16 *val)
{
u32 data;
int ret;
ret = config_access(PCI_ACCESS_READ, bus, devfn, where, &data);
if (where & 2)
data >>= 16;
*val = data & 0xffff;
return ret;
}
static int read_config_dword(struct pci_bus *bus, unsigned int devfn,
int where, u32 *val)
{
int ret;
ret = config_access(PCI_ACCESS_READ, bus, devfn, where, val);
return ret;
}
static int write_config_byte(struct pci_bus *bus, unsigned int devfn,
int where, u8 val)
{
u32 data = 0;
if (config_access(PCI_ACCESS_READ, bus, devfn, where, &data))
return -1;
data = (data & ~(0xff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
if (config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data))
return -1;
return PCIBIOS_SUCCESSFUL;
}
static int write_config_word(struct pci_bus *bus, unsigned int devfn,
int where, u16 val)
{
u32 data = 0;
if (config_access(PCI_ACCESS_READ, bus, devfn, where, &data))
return -1;
data = (data & ~(0xffff << ((where & 3) << 3))) |
(val << ((where & 3) << 3));
if (config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data))
return -1;
return PCIBIOS_SUCCESSFUL;
}
static int write_config_dword(struct pci_bus *bus, unsigned int devfn,
int where, u32 val)
{
if (config_access(PCI_ACCESS_WRITE, bus, devfn, where, &val))
return -1;
return PCIBIOS_SUCCESSFUL;
}
static int config_read(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
switch (size) {
case 1: {
u8 _val;
int rc = read_config_byte(bus, devfn, where, &_val);
*val = _val;
return rc;
}
case 2: {
u16 _val;
int rc = read_config_word(bus, devfn, where, &_val);
*val = _val;
return rc;
}
default:
return read_config_dword(bus, devfn, where, val);
}
}
static int config_write(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
switch (size) {
case 1:
return write_config_byte(bus, devfn, where, (u8) val);
case 2:
return write_config_word(bus, devfn, where, (u16) val);
default:
return write_config_dword(bus, devfn, where, val);
}
}
struct pci_ops au1x_pci_ops = {
config_read,
config_write
};
