linux/arch/x86/kernel/geode_32.c
Andres Salomon ade761496d x86: GEODE: update GPIO API to support setting multiple GPIOs at once
The existing Geode GPIO API only allows for updating one GPIO at once.  There
are instances where users want to update multiple GPIOs at once.  With the
current API, they are given two choices; either ignore the GPIO API:

      outl(0xc000, gpio_base + GPIO_OUTPUT_VAL);
      outl(0xc000, gpio_base + GPIO_OUTPUT_ENABLE);

Alternatively, call each GPIO update separately:

      geode_gpio_set(14, GPIO_OUTPUT_VAL);
      geode_gpio_set(15, GPIO_OUTPUT_VAL);
      geode_gpio_set(14, GPIO_OUTPUT_ENABLE);
      geode_gpio_set(15, GPIO_OUTPUT_ENABLE);

Neither are desirable.  This patch changes the GPIO API to allow for setting
of multiple GPIOs at once; rather than being passed an integer, we pass
a bitmask and provide a translation function.  The above code would now
look like this:

      geode_gpio_set(geode_gpio(14)|geode_gpio(15), GPIO_OUTPUT_VAL);
      geode_gpio_set(geode_gpio(14)|geode_gpio(15), GPIO_OUTPUT_ENABLE);

Since there are no upstream users of the GPIO API yet (afaik), best to
change this now.  This also adds a bit of sanity checking; it is no
longer possible to use a GPIO above 28.

Note the semantics of geode_gpio_isset() have changed:
geode_gpio_isset(geode_gpio(3)|geode_gpio(4), ...)
will only return true iff both GPIOs are set.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30 13:33:35 +01:00

178 lines
3.5 KiB
C

/*
* AMD Geode southbridge support code
* Copyright (C) 2006, Advanced Micro Devices, Inc.
* Copyright (C) 2007, Andres Salomon <dilinger@debian.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <asm/msr.h>
#include <asm/geode.h>
static struct {
char *name;
u32 msr;
int size;
u32 base;
} lbars[] = {
{ "geode-pms", MSR_LBAR_PMS, LBAR_PMS_SIZE, 0 },
{ "geode-acpi", MSR_LBAR_ACPI, LBAR_ACPI_SIZE, 0 },
{ "geode-gpio", MSR_LBAR_GPIO, LBAR_GPIO_SIZE, 0 },
{ "geode-mfgpt", MSR_LBAR_MFGPT, LBAR_MFGPT_SIZE, 0 }
};
static void __init init_lbars(void)
{
u32 lo, hi;
int i;
for (i = 0; i < ARRAY_SIZE(lbars); i++) {
rdmsr(lbars[i].msr, lo, hi);
if (hi & 0x01)
lbars[i].base = lo & 0x0000ffff;
if (lbars[i].base == 0)
printk(KERN_ERR "geode: Couldn't initialize '%s'\n",
lbars[i].name);
}
}
int geode_get_dev_base(unsigned int dev)
{
BUG_ON(dev >= ARRAY_SIZE(lbars));
return lbars[dev].base;
}
EXPORT_SYMBOL_GPL(geode_get_dev_base);
/* === GPIO API === */
void geode_gpio_set(u32 gpio, unsigned int reg)
{
u32 base = geode_get_dev_base(GEODE_DEV_GPIO);
if (!base)
return;
/* low bank register */
if (gpio & 0xFFFF)
outl(gpio & 0xFFFF, base + reg);
/* high bank register */
gpio >>= 16;
if (gpio)
outl(gpio, base + 0x80 + reg);
}
EXPORT_SYMBOL_GPL(geode_gpio_set);
void geode_gpio_clear(u32 gpio, unsigned int reg)
{
u32 base = geode_get_dev_base(GEODE_DEV_GPIO);
if (!base)
return;
/* low bank register */
if (gpio & 0xFFFF)
outl((gpio & 0xFFFF) << 16, base + reg);
/* high bank register */
gpio &= (0xFFFF << 16);
if (gpio)
outl(gpio, base + 0x80 + reg);
}
EXPORT_SYMBOL_GPL(geode_gpio_clear);
int geode_gpio_isset(u32 gpio, unsigned int reg)
{
u32 base = geode_get_dev_base(GEODE_DEV_GPIO);
u32 val;
if (!base)
return 0;
/* low bank register */
if (gpio & 0xFFFF) {
val = inl(base + reg) & (gpio & 0xFFFF);
if ((gpio & 0xFFFF) == val)
return 1;
}
/* high bank register */
gpio >>= 16;
if (gpio) {
val = inl(base + 0x80 + reg) & gpio;
if (gpio == val)
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(geode_gpio_isset);
void geode_gpio_set_irq(unsigned int group, unsigned int irq)
{
u32 lo, hi;
if (group > 7 || irq > 15)
return;
rdmsr(MSR_PIC_ZSEL_HIGH, lo, hi);
lo &= ~(0xF << (group * 4));
lo |= (irq & 0xF) << (group * 4);
wrmsr(MSR_PIC_ZSEL_HIGH, lo, hi);
}
EXPORT_SYMBOL_GPL(geode_gpio_set_irq);
void geode_gpio_setup_event(unsigned int gpio, int pair, int pme)
{
u32 base = geode_get_dev_base(GEODE_DEV_GPIO);
u32 offset, shift, val;
if (gpio >= 24)
offset = GPIO_MAP_W;
else if (gpio >= 16)
offset = GPIO_MAP_Z;
else if (gpio >= 8)
offset = GPIO_MAP_Y;
else
offset = GPIO_MAP_X;
shift = (gpio % 8) * 4;
val = inl(base + offset);
/* Clear whatever was there before */
val &= ~(0xF << shift);
/* And set the new value */
val |= ((pair & 7) << shift);
/* Set the PME bit if this is a PME event */
if (pme)
val |= (1 << (shift + 3));
outl(val, base + offset);
}
EXPORT_SYMBOL_GPL(geode_gpio_setup_event);
static int __init geode_southbridge_init(void)
{
int timers;
if (!is_geode())
return -ENODEV;
init_lbars();
timers = geode_mfgpt_detect();
printk(KERN_INFO "geode: %d MFGPT timers available.\n", timers);
return 0;
}
postcore_initcall(geode_southbridge_init);