linux/arch/sh/boards/mach-sdk7786/setup.c
Paul Mundt b6b77b2d5f sh: pci: Support secondary FPGA-driven PCIe clocks on SDK7786.
The SDK7786 FPGA has secondary control over the PCIe clocks, specifically
relating to the slots and oscillator. This ties the FPGA clocks in to the
clock framework and balances the refcounting similar to how the primary
on-chip clocks are managed. While the on-chip clocks are per-port, the
FPGA clock enable/disable is global for the entire block.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-10-14 08:44:55 +09:00

259 lines
5.8 KiB
C

/*
* Renesas Technology Europe SDK7786 Support.
*
* Copyright (C) 2010 Matt Fleming
* Copyright (C) 2010 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/smsc911x.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/clk.h>
#include <mach/fpga.h>
#include <mach/irq.h>
#include <asm/machvec.h>
#include <asm/heartbeat.h>
#include <asm/sizes.h>
#include <asm/clock.h>
#include <asm/clkdev.h>
#include <asm/reboot.h>
#include <asm/smp-ops.h>
static struct resource heartbeat_resource = {
.start = 0x07fff8b0,
.end = 0x07fff8b0 + sizeof(u16) - 1,
.flags = IORESOURCE_MEM | IORESOURCE_MEM_16BIT,
};
static struct platform_device heartbeat_device = {
.name = "heartbeat",
.id = -1,
.num_resources = 1,
.resource = &heartbeat_resource,
};
static struct resource smsc911x_resources[] = {
[0] = {
.name = "smsc911x-memory",
.start = 0x07ffff00,
.end = 0x07ffff00 + SZ_256 - 1,
.flags = IORESOURCE_MEM,
},
[1] = {
.name = "smsc911x-irq",
.start = evt2irq(0x2c0),
.end = evt2irq(0x2c0),
.flags = IORESOURCE_IRQ,
},
};
static struct smsc911x_platform_config smsc911x_config = {
.irq_polarity = SMSC911X_IRQ_POLARITY_ACTIVE_LOW,
.irq_type = SMSC911X_IRQ_TYPE_OPEN_DRAIN,
.flags = SMSC911X_USE_32BIT,
.phy_interface = PHY_INTERFACE_MODE_MII,
};
static struct platform_device smsc911x_device = {
.name = "smsc911x",
.id = -1,
.num_resources = ARRAY_SIZE(smsc911x_resources),
.resource = smsc911x_resources,
.dev = {
.platform_data = &smsc911x_config,
},
};
static struct resource smbus_fpga_resource = {
.start = 0x07fff9e0,
.end = 0x07fff9e0 + SZ_32 - 1,
.flags = IORESOURCE_MEM,
};
static struct platform_device smbus_fpga_device = {
.name = "i2c-sdk7786",
.id = 0,
.num_resources = 1,
.resource = &smbus_fpga_resource,
};
static struct resource smbus_pcie_resource = {
.start = 0x07fffc30,
.end = 0x07fffc30 + SZ_32 - 1,
.flags = IORESOURCE_MEM,
};
static struct platform_device smbus_pcie_device = {
.name = "i2c-sdk7786",
.id = 1,
.num_resources = 1,
.resource = &smbus_pcie_resource,
};
static struct i2c_board_info __initdata sdk7786_i2c_devices[] = {
{
I2C_BOARD_INFO("max6900", 0x68),
},
};
static struct platform_device *sh7786_devices[] __initdata = {
&heartbeat_device,
&smsc911x_device,
&smbus_fpga_device,
&smbus_pcie_device,
};
static int sdk7786_i2c_setup(void)
{
unsigned int tmp;
/*
* Hand over I2C control to the FPGA.
*/
tmp = fpga_read_reg(SBCR);
tmp &= ~SCBR_I2CCEN;
tmp |= SCBR_I2CMEN;
fpga_write_reg(tmp, SBCR);
return i2c_register_board_info(0, sdk7786_i2c_devices,
ARRAY_SIZE(sdk7786_i2c_devices));
}
static int __init sdk7786_devices_setup(void)
{
int ret;
ret = platform_add_devices(sh7786_devices, ARRAY_SIZE(sh7786_devices));
if (unlikely(ret != 0))
return ret;
return sdk7786_i2c_setup();
}
__initcall(sdk7786_devices_setup);
static int sdk7786_mode_pins(void)
{
return fpga_read_reg(MODSWR);
}
/*
* FPGA-driven PCIe clocks
*
* Historically these include the oscillator, clock B (slots 2/3/4) and
* clock A (slot 1 and the CPU clock). Newer revs of the PCB shove
* everything under a single PCIe clocks enable bit that happens to map
* to the same bit position as the oscillator bit for earlier FPGA
* versions.
*
* Given that the legacy clocks have the side-effect of shutting the CPU
* off through the FPGA along with the PCI slots, we simply leave them in
* their initial state and don't bother registering them with the clock
* framework.
*/
static int sdk7786_pcie_clk_enable(struct clk *clk)
{
fpga_write_reg(fpga_read_reg(PCIECR) | PCIECR_CLKEN, PCIECR);
return 0;
}
static void sdk7786_pcie_clk_disable(struct clk *clk)
{
fpga_write_reg(fpga_read_reg(PCIECR) & ~PCIECR_CLKEN, PCIECR);
}
static struct clk_ops sdk7786_pcie_clk_ops = {
.enable = sdk7786_pcie_clk_enable,
.disable = sdk7786_pcie_clk_disable,
};
static struct clk sdk7786_pcie_clk = {
.ops = &sdk7786_pcie_clk_ops,
};
static struct clk_lookup sdk7786_pcie_cl = {
.con_id = "pcie_plat_clk",
.clk = &sdk7786_pcie_clk,
};
static int sdk7786_clk_init(void)
{
struct clk *clk;
int ret;
/*
* Only handle the EXTAL case, anyone interfacing a crystal
* resonator will need to provide their own input clock.
*/
if (test_mode_pin(MODE_PIN9))
return -EINVAL;
clk = clk_get(NULL, "extal");
if (!clk || IS_ERR(clk))
return PTR_ERR(clk);
ret = clk_set_rate(clk, 33333333);
clk_put(clk);
/*
* Setup the FPGA clocks.
*/
ret = clk_register(&sdk7786_pcie_clk);
if (unlikely(ret)) {
pr_err("FPGA clock registration failed\n");
return ret;
}
clkdev_add(&sdk7786_pcie_cl);
return 0;
}
static void sdk7786_restart(char *cmd)
{
fpga_write_reg(0xa5a5, SRSTR);
}
static void sdk7786_power_off(void)
{
fpga_write_reg(fpga_read_reg(PWRCR) | PWRCR_PDWNREQ, PWRCR);
/*
* It can take up to 20us for the R8C to do its job, back off and
* wait a bit until we've been shut off. Even though newer FPGA
* versions don't set the ACK bit, the latency issue remains.
*/
while ((fpga_read_reg(PWRCR) & PWRCR_PDWNACK) == 0)
cpu_sleep();
}
/* Initialize the board */
static void __init sdk7786_setup(char **cmdline_p)
{
pr_info("Renesas Technology Europe SDK7786 support:\n");
sdk7786_fpga_init();
pr_info("\tPCB revision:\t%d\n", fpga_read_reg(PCBRR) & 0xf);
machine_ops.restart = sdk7786_restart;
pm_power_off = sdk7786_power_off;
register_smp_ops(&shx3_smp_ops);
}
/*
* The Machine Vector
*/
static struct sh_machine_vector mv_sdk7786 __initmv = {
.mv_name = "SDK7786",
.mv_setup = sdk7786_setup,
.mv_mode_pins = sdk7786_mode_pins,
.mv_clk_init = sdk7786_clk_init,
.mv_init_irq = sdk7786_init_irq,
};