/*
* linux/arch/arm/mach-sa1100/pci-nanoengine.c
*
* PCI functions for BSE nanoEngine PCI
*
* Copyright (C) 2010 Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
*
* 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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <asm/mach/pci.h>
#include <asm/mach-types.h>
#include <mach/nanoengine.h>
#include <mach/hardware.h>
static DEFINE_SPINLOCK(nano_lock);
static int nanoengine_get_pci_address(struct pci_bus *bus,
unsigned int devfn, int where, unsigned long *address)
{
int ret = PCIBIOS_DEVICE_NOT_FOUND;
unsigned int busnr = bus->number;
*address = NANO_PCI_CONFIG_SPACE_VIRT +
((bus->number << 16) | (devfn << 8) | (where & ~3));
ret = (busnr > 255 || devfn > 255 || where > 255) ?
PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
return ret;
}
static int nanoengine_read_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 *val)
{
int ret;
unsigned long address;
unsigned long flags;
u32 v;
/* nanoEngine PCI bridge does not return -1 for a non-existing
* device. We must fake the answer. We know that the only valid
* device is device zero at bus 0, which is the network chip. */
if (bus->number != 0 || (devfn >> 3) != 0) {
v = -1;
nanoengine_get_pci_address(bus, devfn, where, &address);
goto exit_function;
}
spin_lock_irqsave(&nano_lock, flags);
ret = nanoengine_get_pci_address(bus, devfn, where, &address);
if (ret != PCIBIOS_SUCCESSFUL)
return ret;
v = __raw_readl(address);
spin_unlock_irqrestore(&nano_lock, flags);
v >>= ((where & 3) * 8);
v &= (unsigned long)(-1) >> ((4 - size) * 8);
exit_function:
*val = v;
return PCIBIOS_SUCCESSFUL;
}
static int nanoengine_write_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 val)
{
int ret;
unsigned long address;
unsigned long flags;
unsigned shift;
u32 v;
shift = (where & 3) * 8;
spin_lock_irqsave(&nano_lock, flags);
ret = nanoengine_get_pci_address(bus, devfn, where, &address);
if (ret != PCIBIOS_SUCCESSFUL)
return ret;
v = __raw_readl(address);
switch (size) {
case 1:
v &= ~(0xFF << shift);
v |= val << shift;
break;
case 2:
v &= ~(0xFFFF << shift);
v |= val << shift;
break;
case 4:
v = val;
break;
}
__raw_writel(v, address);
spin_unlock_irqrestore(&nano_lock, flags);
return PCIBIOS_SUCCESSFUL;
}
static struct pci_ops pci_nano_ops = {
.read = nanoengine_read_config,
.write = nanoengine_write_config,
};
static int __init pci_nanoengine_map_irq(const struct pci_dev *dev, u8 slot,
u8 pin)
{
return NANOENGINE_IRQ_GPIO_PCI;
}
struct pci_bus * __init pci_nanoengine_scan_bus(int nr, struct pci_sys_data *sys)
{
return pci_scan_root_bus(NULL, sys->busnr, &pci_nano_ops, sys,
&sys->resources);
}
static struct resource pci_io_ports = {
.name = "PCI IO",
.start = 0x400,
.end = 0x7FF,
.flags = IORESOURCE_IO,
};
static struct resource pci_non_prefetchable_memory = {
.name = "PCI non-prefetchable",
.start = NANO_PCI_MEM_RW_PHYS,
/* nanoEngine documentation says there is a 1 Megabyte window here,
* but PCI reports just 128 + 8 kbytes. */
.end = NANO_PCI_MEM_RW_PHYS + NANO_PCI_MEM_RW_SIZE - 1,
/* .end = NANO_PCI_MEM_RW_PHYS + SZ_128K + SZ_8K - 1,*/
.flags = IORESOURCE_MEM,
};
/*
* nanoEngine PCI reports 1 Megabyte of prefetchable memory, but it
* overlaps with previously defined memory.
*
* Here is what happens:
*
# dmesg
...
pci 0000:00:00.0: [8086:1209] type 0 class 0x000200
pci 0000:00:00.0: reg 10: [mem 0x00021000-0x00021fff]
pci 0000:00:00.0: reg 14: [io 0x0000-0x003f]
pci 0000:00:00.0: reg 18: [mem 0x00000000-0x0001ffff]
pci 0000:00:00.0: reg 30: [mem 0x00000000-0x000fffff pref]
pci 0000:00:00.0: supports D1 D2
pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot
pci 0000:00:00.0: PME# disabled
PCI: bus0: Fast back to back transfers enabled
pci 0000:00:00.0: BAR 6: can't assign mem pref (size 0x100000)
pci 0000:00:00.0: BAR 2: assigned [mem 0x18600000-0x1861ffff]
pci 0000:00:00.0: BAR 2: set to [mem 0x18600000-0x1861ffff] (PCI address [0x0-0x1ffff])
pci 0000:00:00.0: BAR 0: assigned [mem 0x18620000-0x18620fff]
pci 0000:00:00.0: BAR 0: set to [mem 0x18620000-0x18620fff] (PCI address [0x20000-0x20fff])
pci 0000:00:00.0: BAR 1: assigned [io 0x0400-0x043f]
pci 0000:00:00.0: BAR 1: set to [io 0x0400-0x043f] (PCI address [0x0-0x3f])
*
* On the other hand, if we do not request the prefetchable memory resource,
* linux will alloc it first and the two non-prefetchable memory areas that
* are our real interest will not be mapped. So we choose to map it to an
* unused area. It gets recognized as expansion ROM, but becomes disabled.
*
* Here is what happens then:
*
# dmesg
...
pci 0000:00:00.0: [8086:1209] type 0 class 0x000200
pci 0000:00:00.0: reg 10: [mem 0x00021000-0x00021fff]
pci 0000:00:00.0: reg 14: [io 0x0000-0x003f]
pci 0000:00:00.0: reg 18: [mem 0x00000000-0x0001ffff]
pci 0000:00:00.0: reg 30: [mem 0x00000000-0x000fffff pref]
pci 0000:00:00.0: supports D1 D2
pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot
pci 0000:00:00.0: PME# disabled
PCI: bus0: Fast back to back transfers enabled
pci 0000:00:00.0: BAR 6: assigned [mem 0x78000000-0x780fffff pref]
pci 0000:00:00.0: BAR 2: assigned [mem 0x18600000-0x1861ffff]
pci 0000:00:00.0: BAR 2: set to [mem 0x18600000-0x1861ffff] (PCI address [0x0-0x1ffff])
pci 0000:00:00.0: BAR 0: assigned [mem 0x18620000-0x18620fff]
pci 0000:00:00.0: BAR 0: set to [mem 0x18620000-0x18620fff] (PCI address [0x20000-0x20fff])
pci 0000:00:00.0: BAR 1: assigned [io 0x0400-0x043f]
pci 0000:00:00.0: BAR 1: set to [io 0x0400-0x043f] (PCI address [0x0-0x3f])
# lspci -vv -s 0000:00:00.0
00:00.0 Class 0200: Device 8086:1209 (rev 09)
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR+ <PERR+ INTx-
Latency: 0 (2000ns min, 14000ns max), Cache Line Size: 32 bytes
Interrupt: pin A routed to IRQ 0
Region 0: Memory at 18620000 (32-bit, non-prefetchable) [size=4K]
Region 1: I/O ports at 0400 [size=64]
Region 2: [virtual] Memory at 18600000 (32-bit, non-prefetchable) [size=128K]
[virtual] Expansion ROM at 78000000 [disabled] [size=1M]
Capabilities: [dc] Power Management version 2
Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=2 PME-
Kernel driver in use: e100
Kernel modules: e100
*
*/
static struct resource pci_prefetchable_memory = {
.name = "PCI prefetchable",
.start = 0x78000000,
.end = 0x78000000 + NANO_PCI_MEM_RW_SIZE - 1,
.flags = IORESOURCE_MEM | IORESOURCE_PREFETCH,
};
static int __init pci_nanoengine_setup_resources(struct pci_sys_data *sys)
{
if (request_resource(&ioport_resource, &pci_io_ports)) {
printk(KERN_ERR "PCI: unable to allocate io port region\n");
return -EBUSY;
}
if (request_resource(&iomem_resource, &pci_non_prefetchable_memory)) {
release_resource(&pci_io_ports);
printk(KERN_ERR "PCI: unable to allocate non prefetchable\n");
return -EBUSY;
}
if (request_resource(&iomem_resource, &pci_prefetchable_memory)) {
release_resource(&pci_io_ports);
release_resource(&pci_non_prefetchable_memory);
printk(KERN_ERR "PCI: unable to allocate prefetchable\n");
return -EBUSY;
}
pci_add_resource(&sys->resources, &pci_io_ports);
pci_add_resource(&sys->resources, &pci_non_prefetchable_memory);
pci_add_resource(&sys->resources, &pci_prefetchable_memory);
return 1;
}
int __init pci_nanoengine_setup(int nr, struct pci_sys_data *sys)
{
int ret = 0;
pcibios_min_io = 0;
pcibios_min_mem = 0;
if (nr == 0) {
sys->mem_offset = NANO_PCI_MEM_RW_PHYS;
sys->io_offset = 0x400;
ret = pci_nanoengine_setup_resources(sys);
/* Enable alternate memory bus master mode, see
* "Intel StrongARM SA1110 Developer's Manual",
* section 10.8, "Alternate Memory Bus Master Mode". */
GPDR = (GPDR & ~GPIO_MBREQ) | GPIO_MBGNT;
GAFR |= GPIO_MBGNT | GPIO_MBREQ;
TUCR |= TUCR_MBGPIO;
}
return ret;
}
static struct hw_pci nanoengine_pci __initdata = {
.map_irq = pci_nanoengine_map_irq,
.nr_controllers = 1,
.scan = pci_nanoengine_scan_bus,
.setup = pci_nanoengine_setup,
};
static int __init nanoengine_pci_init(void)
{
if (machine_is_nanoengine())
pci_common_init(&nanoengine_pci);
return 0;
}
subsys_initcall(nanoengine_pci_init);