kernel_optimize_test/arch/arm/mach-kirkwood/pcie.c
Rabeeh Khoury e8b2b7ba12 [ARM] Kirkwood: clock gating for unused peripherals
To save power:

1. Enabling clock gating of unused peripherals

2. PLL and PHY of the units are also disabled (when possible.

Signed-off-by: Rabeeh Khoury <rabeeh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-06-08 13:04:58 -04:00

192 lines
4.2 KiB
C

/*
* arch/arm/mach-kirkwood/pcie.c
*
* PCIe functions for Marvell Kirkwood SoCs
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/mbus.h>
#include <asm/irq.h>
#include <asm/mach/pci.h>
#include <plat/pcie.h>
#include <mach/bridge-regs.h>
#include "common.h"
#define PCIE_BASE ((void __iomem *)PCIE_VIRT_BASE)
void __init kirkwood_pcie_id(u32 *dev, u32 *rev)
{
*dev = orion_pcie_dev_id(PCIE_BASE);
*rev = orion_pcie_rev(PCIE_BASE);
}
static int pcie_valid_config(int bus, int dev)
{
/*
* Don't go out when trying to access --
* 1. nonexisting device on local bus
* 2. where there's no device connected (no link)
*/
if (bus == 0 && dev == 0)
return 1;
if (!orion_pcie_link_up(PCIE_BASE))
return 0;
if (bus == 0 && dev != 1)
return 0;
return 1;
}
/*
* PCIe config cycles are done by programming the PCIE_CONF_ADDR register
* and then reading the PCIE_CONF_DATA register. Need to make sure these
* transactions are atomic.
*/
static DEFINE_SPINLOCK(kirkwood_pcie_lock);
static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
int size, u32 *val)
{
unsigned long flags;
int ret;
if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
*val = 0xffffffff;
return PCIBIOS_DEVICE_NOT_FOUND;
}
spin_lock_irqsave(&kirkwood_pcie_lock, flags);
ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
spin_unlock_irqrestore(&kirkwood_pcie_lock, flags);
return ret;
}
static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
int where, int size, u32 val)
{
unsigned long flags;
int ret;
if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
return PCIBIOS_DEVICE_NOT_FOUND;
spin_lock_irqsave(&kirkwood_pcie_lock, flags);
ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
spin_unlock_irqrestore(&kirkwood_pcie_lock, flags);
return ret;
}
static struct pci_ops pcie_ops = {
.read = pcie_rd_conf,
.write = pcie_wr_conf,
};
static int kirkwood_pcie_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;
extern unsigned int kirkwood_clk_ctrl;
/*
* Generic PCIe unit setup.
*/
orion_pcie_setup(PCIE_BASE, &kirkwood_mbus_dram_info);
/*
* Request resources.
*/
res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
if (!res)
panic("pcie_setup unable to alloc resources");
/*
* IORESOURCE_IO
*/
res[0].name = "PCIe I/O Space";
res[0].flags = IORESOURCE_IO;
res[0].start = KIRKWOOD_PCIE_IO_PHYS_BASE;
res[0].end = res[0].start + KIRKWOOD_PCIE_IO_SIZE - 1;
if (request_resource(&ioport_resource, &res[0]))
panic("Request PCIe IO resource failed\n");
sys->resource[0] = &res[0];
/*
* IORESOURCE_MEM
*/
res[1].name = "PCIe Memory Space";
res[1].flags = IORESOURCE_MEM;
res[1].start = KIRKWOOD_PCIE_MEM_PHYS_BASE;
res[1].end = res[1].start + KIRKWOOD_PCIE_MEM_SIZE - 1;
if (request_resource(&iomem_resource, &res[1]))
panic("Request PCIe Memory resource failed\n");
sys->resource[1] = &res[1];
sys->resource[2] = NULL;
sys->io_offset = 0;
kirkwood_clk_ctrl |= CGC_PEX0;
return 1;
}
static void __devinit rc_pci_fixup(struct pci_dev *dev)
{
/*
* Prevent enumeration of root complex.
*/
if (dev->bus->parent == NULL && dev->devfn == 0) {
int i;
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
dev->resource[i].start = 0;
dev->resource[i].end = 0;
dev->resource[i].flags = 0;
}
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
static struct pci_bus __init *
kirkwood_pcie_scan_bus(int nr, struct pci_sys_data *sys)
{
struct pci_bus *bus;
if (nr == 0) {
bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
} else {
bus = NULL;
BUG();
}
return bus;
}
static int __init kirkwood_pcie_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
return IRQ_KIRKWOOD_PCIE;
}
static struct hw_pci kirkwood_pci __initdata = {
.nr_controllers = 1,
.swizzle = pci_std_swizzle,
.setup = kirkwood_pcie_setup,
.scan = kirkwood_pcie_scan_bus,
.map_irq = kirkwood_pcie_map_irq,
};
void __init kirkwood_pcie_init(void)
{
pci_common_init(&kirkwood_pci);
}