linux/drivers/ssb/pcmcia.c
Michael Buesch 60d78c4473 ssb: Fix PCMCIA-host lowlevel bus access
This fixes the lowlevel bus access routines for
PCMCIA based devices.

There are still a few issues with register access sideeffects after
this patch. This will be addressed in a later patch.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-11-10 22:01:53 -08:00

273 lines
6.2 KiB
C

/*
* Sonics Silicon Backplane
* PCMCIA-Hostbus related functions
*
* Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2007 Michael Buesch <mb@bu3sch.de>
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/ssb/ssb.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <pcmcia/cs_types.h>
#include <pcmcia/cs.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/ciscode.h>
#include <pcmcia/ds.h>
#include <pcmcia/cisreg.h>
#include "ssb_private.h"
/* Define the following to 1 to enable a printk on each coreswitch. */
#define SSB_VERBOSE_PCMCIACORESWITCH_DEBUG 0
int ssb_pcmcia_switch_coreidx(struct ssb_bus *bus,
u8 coreidx)
{
struct pcmcia_device *pdev = bus->host_pcmcia;
int err;
int attempts = 0;
u32 cur_core;
conf_reg_t reg;
u32 addr;
u32 read_addr;
addr = (coreidx * SSB_CORE_SIZE) + SSB_ENUM_BASE;
while (1) {
reg.Action = CS_WRITE;
reg.Offset = 0x2E;
reg.Value = (addr & 0x0000F000) >> 12;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
reg.Offset = 0x30;
reg.Value = (addr & 0x00FF0000) >> 16;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
reg.Offset = 0x32;
reg.Value = (addr & 0xFF000000) >> 24;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
read_addr = 0;
reg.Action = CS_READ;
reg.Offset = 0x2E;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
read_addr |= ((u32)(reg.Value & 0x0F)) << 12;
reg.Offset = 0x30;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
read_addr |= ((u32)reg.Value) << 16;
reg.Offset = 0x32;
err = pcmcia_access_configuration_register(pdev, &reg);
if (err != CS_SUCCESS)
goto error;
read_addr |= ((u32)reg.Value) << 24;
cur_core = (read_addr - SSB_ENUM_BASE) / SSB_CORE_SIZE;
if (cur_core == coreidx)
break;
if (attempts++ > SSB_BAR0_MAX_RETRIES)
goto error;
udelay(10);
}
return 0;
error:
ssb_printk(KERN_ERR PFX "Failed to switch to core %u\n", coreidx);
return -ENODEV;
}
int ssb_pcmcia_switch_core(struct ssb_bus *bus,
struct ssb_device *dev)
{
int err;
unsigned long flags;
#if SSB_VERBOSE_PCMCIACORESWITCH_DEBUG
ssb_printk(KERN_INFO PFX
"Switching to %s core, index %d\n",
ssb_core_name(dev->id.coreid),
dev->core_index);
#endif
spin_lock_irqsave(&bus->bar_lock, flags);
err = ssb_pcmcia_switch_coreidx(bus, dev->core_index);
if (!err)
bus->mapped_device = dev;
spin_unlock_irqrestore(&bus->bar_lock, flags);
return err;
}
int ssb_pcmcia_switch_segment(struct ssb_bus *bus, u8 seg)
{
int attempts = 0;
unsigned long flags;
conf_reg_t reg;
int res, err = 0;
SSB_WARN_ON((seg != 0) && (seg != 1));
reg.Offset = 0x34;
reg.Function = 0;
spin_lock_irqsave(&bus->bar_lock, flags);
while (1) {
reg.Action = CS_WRITE;
reg.Value = seg;
res = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
if (unlikely(res != CS_SUCCESS))
goto error;
reg.Value = 0xFF;
reg.Action = CS_READ;
res = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
if (unlikely(res != CS_SUCCESS))
goto error;
if (reg.Value == seg)
break;
if (unlikely(attempts++ > SSB_BAR0_MAX_RETRIES))
goto error;
udelay(10);
}
bus->mapped_pcmcia_seg = seg;
out_unlock:
spin_unlock_irqrestore(&bus->bar_lock, flags);
return err;
error:
ssb_printk(KERN_ERR PFX "Failed to switch pcmcia segment\n");
err = -ENODEV;
goto out_unlock;
}
static int select_core_and_segment(struct ssb_device *dev,
u16 *offset)
{
struct ssb_bus *bus = dev->bus;
int err;
u8 need_segment;
if (*offset >= 0x800) {
*offset -= 0x800;
need_segment = 1;
} else
need_segment = 0;
if (unlikely(dev != bus->mapped_device)) {
err = ssb_pcmcia_switch_core(bus, dev);
if (unlikely(err))
return err;
}
if (unlikely(need_segment != bus->mapped_pcmcia_seg)) {
err = ssb_pcmcia_switch_segment(bus, need_segment);
if (unlikely(err))
return err;
}
return 0;
}
static u16 ssb_pcmcia_read16(struct ssb_device *dev, u16 offset)
{
struct ssb_bus *bus = dev->bus;
if (unlikely(select_core_and_segment(dev, &offset)))
return 0xFFFF;
return readw(bus->mmio + offset);
}
static u32 ssb_pcmcia_read32(struct ssb_device *dev, u16 offset)
{
struct ssb_bus *bus = dev->bus;
u32 lo, hi;
if (unlikely(select_core_and_segment(dev, &offset)))
return 0xFFFFFFFF;
lo = readw(bus->mmio + offset);
hi = readw(bus->mmio + offset + 2);
return (lo | (hi << 16));
}
static void ssb_pcmcia_write16(struct ssb_device *dev, u16 offset, u16 value)
{
struct ssb_bus *bus = dev->bus;
if (unlikely(select_core_and_segment(dev, &offset)))
return;
writew(value, bus->mmio + offset);
}
static void ssb_pcmcia_write32(struct ssb_device *dev, u16 offset, u32 value)
{
struct ssb_bus *bus = dev->bus;
if (unlikely(select_core_and_segment(dev, &offset)))
return;
writeb((value & 0xFF000000) >> 24, bus->mmio + offset + 3);
writeb((value & 0x00FF0000) >> 16, bus->mmio + offset + 2);
writeb((value & 0x0000FF00) >> 8, bus->mmio + offset + 1);
writeb((value & 0x000000FF) >> 0, bus->mmio + offset + 0);
}
/* Not "static", as it's used in main.c */
const struct ssb_bus_ops ssb_pcmcia_ops = {
.read16 = ssb_pcmcia_read16,
.read32 = ssb_pcmcia_read32,
.write16 = ssb_pcmcia_write16,
.write32 = ssb_pcmcia_write32,
};
int ssb_pcmcia_get_invariants(struct ssb_bus *bus,
struct ssb_init_invariants *iv)
{
//TODO
return 0;
}
int ssb_pcmcia_init(struct ssb_bus *bus)
{
conf_reg_t reg;
int err;
if (bus->bustype != SSB_BUSTYPE_PCMCIA)
return 0;
/* Switch segment to a known state and sync
* bus->mapped_pcmcia_seg with hardware state. */
ssb_pcmcia_switch_segment(bus, 0);
/* Init IRQ routing */
reg.Action = CS_READ;
reg.Function = 0;
if (bus->chip_id == 0x4306)
reg.Offset = 0x00;
else
reg.Offset = 0x80;
err = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
if (err != CS_SUCCESS)
goto error;
reg.Action = CS_WRITE;
reg.Value |= 0x04 | 0x01;
err = pcmcia_access_configuration_register(bus->host_pcmcia, &reg);
if (err != CS_SUCCESS)
goto error;
return 0;
error:
return -ENODEV;
}