cs5535: add a generic MFGPT driver

This is based on the old code on arch/x86/kernel/mfgpt_32.c, except it's
not x86 specific, it's modular, and it makes use of a PCI BAR rather than
a random MSR.  Currently module unloading is not supported; it's uncertain
whether or not it can be made work with the hardware.

[akpm@linux-foundation.org: add X86 dependency]
Signed-off-by: Andres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andres Salomon 2009-12-14 18:00:37 -08:00 committed by Linus Torvalds
parent 3c55494670
commit 82dca611bb
5 changed files with 462 additions and 40 deletions

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@ -47,16 +47,6 @@ extern int geode_get_dev_base(unsigned int dev);
#define MSR_DIVIL_SOFT_RESET 0x51400017
#define MSR_PIC_YSEL_LOW 0x51400020
#define MSR_PIC_YSEL_HIGH 0x51400021
#define MSR_PIC_ZSEL_LOW 0x51400022
#define MSR_PIC_ZSEL_HIGH 0x51400023
#define MSR_PIC_IRQM_LPC 0x51400025
#define MSR_MFGPT_IRQ 0x51400028
#define MSR_MFGPT_NR 0x51400029
#define MSR_MFGPT_SETUP 0x5140002B
#define MSR_LX_SPARE_MSR 0x80000011 /* DC-specific */
#define MSR_GX_GLD_MSR_CONFIG 0xC0002001
@ -169,36 +159,6 @@ static inline int geode_has_vsa2(void)
}
#endif
/* MFGPTs */
#define MFGPT_MAX_TIMERS 8
#define MFGPT_TIMER_ANY (-1)
#define MFGPT_DOMAIN_WORKING 1
#define MFGPT_DOMAIN_STANDBY 2
#define MFGPT_DOMAIN_ANY (MFGPT_DOMAIN_WORKING | MFGPT_DOMAIN_STANDBY)
#define MFGPT_CMP1 0
#define MFGPT_CMP2 1
#define MFGPT_EVENT_IRQ 0
#define MFGPT_EVENT_NMI 1
#define MFGPT_EVENT_RESET 3
#define MFGPT_REG_CMP1 0
#define MFGPT_REG_CMP2 2
#define MFGPT_REG_COUNTER 4
#define MFGPT_REG_SETUP 6
#define MFGPT_SETUP_CNTEN (1 << 15)
#define MFGPT_SETUP_CMP2 (1 << 14)
#define MFGPT_SETUP_CMP1 (1 << 13)
#define MFGPT_SETUP_SETUP (1 << 12)
#define MFGPT_SETUP_STOPEN (1 << 11)
#define MFGPT_SETUP_EXTEN (1 << 10)
#define MFGPT_SETUP_REVEN (1 << 5)
#define MFGPT_SETUP_CLKSEL (1 << 4)
static inline void geode_mfgpt_write(int timer, u16 reg, u16 value)
{
u32 base = geode_get_dev_base(GEODE_DEV_MFGPT);

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@ -187,6 +187,30 @@ config SGI_XP
this feature will allow for direct communication between SSIs
based on a network adapter and DMA messaging.
config CS5535_MFGPT
tristate "CS5535/CS5536 Geode Multi-Function General Purpose Timer (MFGPT) support"
depends on PCI && !MGEODE_LX
depends on X86
default n
help
This driver provides access to MFGPT functionality for other
drivers that need timers. MFGPTs are available in the CS5535 and
CS5536 companion chips that are found in AMD Geode and several
other platforms. They have a better resolution and max interval
than the generic PIT, and are suitable for use as high-res timers.
You probably don't want to enable this manually; other drivers that
make use of it should enable it.
config CS5535_MFGPT_DEFAULT_IRQ
int
default 7
help
MFGPTs on the CS5535 require an interrupt. The selected IRQ
can be overridden as a module option as well as by driver that
use the cs5535_mfgpt_ API; however, different architectures might
want to use a different IRQ by default. This is here for
architectures to set as necessary.
config HP_ILO
tristate "Channel interface driver for HP iLO/iLO2 processor"
depends on PCI

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@ -18,6 +18,7 @@ obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
obj-$(CONFIG_KGDB_TESTS) += kgdbts.o
obj-$(CONFIG_SGI_XP) += sgi-xp/
obj-$(CONFIG_SGI_GRU) += sgi-gru/
obj-$(CONFIG_CS5535_MFGPT) += cs5535-mfgpt.o
obj-$(CONFIG_HP_ILO) += hpilo.o
obj-$(CONFIG_ISL29003) += isl29003.o
obj-$(CONFIG_EP93XX_PWM) += ep93xx_pwm.o

370
drivers/misc/cs5535-mfgpt.c Normal file
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@ -0,0 +1,370 @@
/*
* Driver for the CS5535/CS5536 Multi-Function General Purpose Timers (MFGPT)
*
* Copyright (C) 2006, Advanced Micro Devices, Inc.
* Copyright (C) 2007 Andres Salomon <dilinger@debian.org>
* Copyright (C) 2009 Andres Salomon <dilinger@collabora.co.uk>
*
* 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.
*
* The MFGPTs are documented in AMD Geode CS5536 Companion Device Data Book.
*/
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/cs5535.h>
#define DRV_NAME "cs5535-mfgpt"
#define MFGPT_BAR 2
static int mfgpt_reset_timers;
module_param_named(mfgptfix, mfgpt_reset_timers, int, 0644);
MODULE_PARM_DESC(mfgptfix, "Reset the MFGPT timers during init; "
"required by some broken BIOSes (ie, TinyBIOS < 0.99).");
struct cs5535_mfgpt_timer {
struct cs5535_mfgpt_chip *chip;
int nr;
};
static struct cs5535_mfgpt_chip {
DECLARE_BITMAP(avail, MFGPT_MAX_TIMERS);
resource_size_t base;
struct pci_dev *pdev;
spinlock_t lock;
int initialized;
} cs5535_mfgpt_chip;
int cs5535_mfgpt_toggle_event(struct cs5535_mfgpt_timer *timer, int cmp,
int event, int enable)
{
uint32_t msr, mask, value, dummy;
int shift = (cmp == MFGPT_CMP1) ? 0 : 8;
if (!timer) {
WARN_ON(1);
return -EIO;
}
/*
* The register maps for these are described in sections 6.17.1.x of
* the AMD Geode CS5536 Companion Device Data Book.
*/
switch (event) {
case MFGPT_EVENT_RESET:
/*
* XXX: According to the docs, we cannot reset timers above
* 6; that is, resets for 7 and 8 will be ignored. Is this
* a problem? -dilinger
*/
msr = MSR_MFGPT_NR;
mask = 1 << (timer->nr + 24);
break;
case MFGPT_EVENT_NMI:
msr = MSR_MFGPT_NR;
mask = 1 << (timer->nr + shift);
break;
case MFGPT_EVENT_IRQ:
msr = MSR_MFGPT_IRQ;
mask = 1 << (timer->nr + shift);
break;
default:
return -EIO;
}
rdmsr(msr, value, dummy);
if (enable)
value |= mask;
else
value &= ~mask;
wrmsr(msr, value, dummy);
return 0;
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_toggle_event);
int cs5535_mfgpt_set_irq(struct cs5535_mfgpt_timer *timer, int cmp, int *irq,
int enable)
{
uint32_t zsel, lpc, dummy;
int shift;
if (!timer) {
WARN_ON(1);
return -EIO;
}
/*
* Unfortunately, MFGPTs come in pairs sharing their IRQ lines. If VSA
* is using the same CMP of the timer's Siamese twin, the IRQ is set to
* 2, and we mustn't use nor change it.
* XXX: Likewise, 2 Linux drivers might clash if the 2nd overwrites the
* IRQ of the 1st. This can only happen if forcing an IRQ, calling this
* with *irq==0 is safe. Currently there _are_ no 2 drivers.
*/
rdmsr(MSR_PIC_ZSEL_LOW, zsel, dummy);
shift = ((cmp == MFGPT_CMP1 ? 0 : 4) + timer->nr % 4) * 4;
if (((zsel >> shift) & 0xF) == 2)
return -EIO;
/* Choose IRQ: if none supplied, keep IRQ already set or use default */
if (!*irq)
*irq = (zsel >> shift) & 0xF;
if (!*irq)
*irq = CONFIG_CS5535_MFGPT_DEFAULT_IRQ;
/* Can't use IRQ if it's 0 (=disabled), 2, or routed to LPC */
if (*irq < 1 || *irq == 2 || *irq > 15)
return -EIO;
rdmsr(MSR_PIC_IRQM_LPC, lpc, dummy);
if (lpc & (1 << *irq))
return -EIO;
/* All chosen and checked - go for it */
if (cs5535_mfgpt_toggle_event(timer, cmp, MFGPT_EVENT_IRQ, enable))
return -EIO;
if (enable) {
zsel = (zsel & ~(0xF << shift)) | (*irq << shift);
wrmsr(MSR_PIC_ZSEL_LOW, zsel, dummy);
}
return 0;
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_set_irq);
struct cs5535_mfgpt_timer *cs5535_mfgpt_alloc_timer(int timer_nr, int domain)
{
struct cs5535_mfgpt_chip *mfgpt = &cs5535_mfgpt_chip;
struct cs5535_mfgpt_timer *timer = NULL;
unsigned long flags;
int max;
if (!mfgpt->initialized)
goto done;
/* only allocate timers from the working domain if requested */
if (domain == MFGPT_DOMAIN_WORKING)
max = 6;
else
max = MFGPT_MAX_TIMERS;
if (timer_nr >= max) {
/* programmer error. silly programmers! */
WARN_ON(1);
goto done;
}
spin_lock_irqsave(&mfgpt->lock, flags);
if (timer_nr < 0) {
unsigned long t;
/* try to find any available timer */
t = find_first_bit(mfgpt->avail, max);
/* set timer_nr to -1 if no timers available */
timer_nr = t < max ? (int) t : -1;
} else {
/* check if the requested timer's available */
if (test_bit(timer_nr, mfgpt->avail))
timer_nr = -1;
}
if (timer_nr >= 0)
/* if timer_nr is not -1, it's an available timer */
__clear_bit(timer_nr, mfgpt->avail);
spin_unlock_irqrestore(&mfgpt->lock, flags);
if (timer_nr < 0)
goto done;
timer = kmalloc(sizeof(*timer), GFP_KERNEL);
if (!timer) {
/* aw hell */
spin_lock_irqsave(&mfgpt->lock, flags);
__set_bit(timer_nr, mfgpt->avail);
spin_unlock_irqrestore(&mfgpt->lock, flags);
goto done;
}
timer->chip = mfgpt;
timer->nr = timer_nr;
dev_info(&mfgpt->pdev->dev, "registered timer %d\n", timer_nr);
done:
return timer;
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_alloc_timer);
/*
* XXX: This frees the timer memory, but never resets the actual hardware
* timer. The old geode_mfgpt code did this; it would be good to figure
* out a way to actually release the hardware timer. See comments below.
*/
void cs5535_mfgpt_free_timer(struct cs5535_mfgpt_timer *timer)
{
kfree(timer);
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_free_timer);
uint16_t cs5535_mfgpt_read(struct cs5535_mfgpt_timer *timer, uint16_t reg)
{
return inw(timer->chip->base + reg + (timer->nr * 8));
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_read);
void cs5535_mfgpt_write(struct cs5535_mfgpt_timer *timer, uint16_t reg,
uint16_t value)
{
outw(value, timer->chip->base + reg + (timer->nr * 8));
}
EXPORT_SYMBOL_GPL(cs5535_mfgpt_write);
/*
* This is a sledgehammer that resets all MFGPT timers. This is required by
* some broken BIOSes which leave the system in an unstable state
* (TinyBIOS 0.98, for example; fixed in 0.99). It's uncertain as to
* whether or not this secret MSR can be used to release individual timers.
* Jordan tells me that he and Mitch once played w/ it, but it's unclear
* what the results of that were (and they experienced some instability).
*/
static void __init reset_all_timers(void)
{
uint32_t val, dummy;
/* The following undocumented bit resets the MFGPT timers */
val = 0xFF; dummy = 0;
wrmsr(MSR_MFGPT_SETUP, val, dummy);
}
/*
* Check whether any MFGPTs are available for the kernel to use. In most
* cases, firmware that uses AMD's VSA code will claim all timers during
* bootup; we certainly don't want to take them if they're already in use.
* In other cases (such as with VSAless OpenFirmware), the system firmware
* leaves timers available for us to use.
*/
static int __init scan_timers(struct cs5535_mfgpt_chip *mfgpt)
{
struct cs5535_mfgpt_timer timer = { .chip = mfgpt };
unsigned long flags;
int timers = 0;
uint16_t val;
int i;
/* bios workaround */
if (mfgpt_reset_timers)
reset_all_timers();
/* just to be safe, protect this section w/ lock */
spin_lock_irqsave(&mfgpt->lock, flags);
for (i = 0; i < MFGPT_MAX_TIMERS; i++) {
timer.nr = i;
val = cs5535_mfgpt_read(&timer, MFGPT_REG_SETUP);
if (!(val & MFGPT_SETUP_SETUP)) {
__set_bit(i, mfgpt->avail);
timers++;
}
}
spin_unlock_irqrestore(&mfgpt->lock, flags);
return timers;
}
static int __init cs5535_mfgpt_probe(struct pci_dev *pdev,
const struct pci_device_id *pci_id)
{
int err, t;
/* There are two ways to get the MFGPT base address; one is by
* fetching it from MSR_LBAR_MFGPT, the other is by reading the
* PCI BAR info. The latter method is easier (especially across
* different architectures), so we'll stick with that for now. If
* it turns out to be unreliable in the face of crappy BIOSes, we
* can always go back to using MSRs.. */
err = pci_enable_device_io(pdev);
if (err) {
dev_err(&pdev->dev, "can't enable device IO\n");
goto done;
}
err = pci_request_region(pdev, MFGPT_BAR, DRV_NAME);
if (err) {
dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", MFGPT_BAR);
goto done;
}
/* set up the driver-specific struct */
cs5535_mfgpt_chip.base = pci_resource_start(pdev, MFGPT_BAR);
cs5535_mfgpt_chip.pdev = pdev;
spin_lock_init(&cs5535_mfgpt_chip.lock);
dev_info(&pdev->dev, "allocated PCI BAR #%d: base 0x%llx\n", MFGPT_BAR,
(unsigned long long) cs5535_mfgpt_chip.base);
/* detect the available timers */
t = scan_timers(&cs5535_mfgpt_chip);
dev_info(&pdev->dev, DRV_NAME ": %d MFGPT timers available\n", t);
cs5535_mfgpt_chip.initialized = 1;
return 0;
done:
return err;
}
static struct pci_device_id cs5535_mfgpt_pci_tbl[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) },
{ 0, },
};
MODULE_DEVICE_TABLE(pci, cs5535_mfgpt_pci_tbl);
/*
* Just like with the cs5535-gpio driver, we can't use the standard PCI driver
* registration stuff. It only allows only one driver to bind to each PCI
* device, and we want the GPIO and MFGPT drivers to be able to share a PCI
* device. Instead, we manually scan for the PCI device, request a single
* region, and keep track of the devices that we're using.
*/
static int __init cs5535_mfgpt_scan_pci(void)
{
struct pci_dev *pdev;
int err = -ENODEV;
int i;
for (i = 0; i < ARRAY_SIZE(cs5535_mfgpt_pci_tbl); i++) {
pdev = pci_get_device(cs5535_mfgpt_pci_tbl[i].vendor,
cs5535_mfgpt_pci_tbl[i].device, NULL);
if (pdev) {
err = cs5535_mfgpt_probe(pdev,
&cs5535_mfgpt_pci_tbl[i]);
if (err)
pci_dev_put(pdev);
/* we only support a single CS5535/6 southbridge */
break;
}
}
return err;
}
static int __init cs5535_mfgpt_init(void)
{
return cs5535_mfgpt_scan_pci();
}
module_init(cs5535_mfgpt_init);
MODULE_AUTHOR("Andres Salomon <dilinger@collabora.co.uk>");
MODULE_DESCRIPTION("CS5535/CS5536 MFGPT timer driver");
MODULE_LICENSE("GPL");

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@ -18,6 +18,16 @@
#define MSR_LBAR_ACPI 0x5140000E
#define MSR_LBAR_PMS 0x5140000F
#define MSR_PIC_YSEL_LOW 0x51400020
#define MSR_PIC_YSEL_HIGH 0x51400021
#define MSR_PIC_ZSEL_LOW 0x51400022
#define MSR_PIC_ZSEL_HIGH 0x51400023
#define MSR_PIC_IRQM_LPC 0x51400025
#define MSR_MFGPT_IRQ 0x51400028
#define MSR_MFGPT_NR 0x51400029
#define MSR_MFGPT_SETUP 0x5140002B
/* resource sizes */
#define LBAR_GPIO_SIZE 0xFF
#define LBAR_MFGPT_SIZE 0x40
@ -55,4 +65,61 @@ void cs5535_gpio_set(unsigned offset, unsigned int reg);
void cs5535_gpio_clear(unsigned offset, unsigned int reg);
int cs5535_gpio_isset(unsigned offset, unsigned int reg);
/* MFGPTs */
#define MFGPT_MAX_TIMERS 8
#define MFGPT_TIMER_ANY (-1)
#define MFGPT_DOMAIN_WORKING 1
#define MFGPT_DOMAIN_STANDBY 2
#define MFGPT_DOMAIN_ANY (MFGPT_DOMAIN_WORKING | MFGPT_DOMAIN_STANDBY)
#define MFGPT_CMP1 0
#define MFGPT_CMP2 1
#define MFGPT_EVENT_IRQ 0
#define MFGPT_EVENT_NMI 1
#define MFGPT_EVENT_RESET 3
#define MFGPT_REG_CMP1 0
#define MFGPT_REG_CMP2 2
#define MFGPT_REG_COUNTER 4
#define MFGPT_REG_SETUP 6
#define MFGPT_SETUP_CNTEN (1 << 15)
#define MFGPT_SETUP_CMP2 (1 << 14)
#define MFGPT_SETUP_CMP1 (1 << 13)
#define MFGPT_SETUP_SETUP (1 << 12)
#define MFGPT_SETUP_STOPEN (1 << 11)
#define MFGPT_SETUP_EXTEN (1 << 10)
#define MFGPT_SETUP_REVEN (1 << 5)
#define MFGPT_SETUP_CLKSEL (1 << 4)
struct cs5535_mfgpt_timer;
extern uint16_t cs5535_mfgpt_read(struct cs5535_mfgpt_timer *timer,
uint16_t reg);
extern void cs5535_mfgpt_write(struct cs5535_mfgpt_timer *timer, uint16_t reg,
uint16_t value);
extern int cs5535_mfgpt_toggle_event(struct cs5535_mfgpt_timer *timer, int cmp,
int event, int enable);
extern int cs5535_mfgpt_set_irq(struct cs5535_mfgpt_timer *timer, int cmp,
int *irq, int enable);
extern struct cs5535_mfgpt_timer *cs5535_mfgpt_alloc_timer(int timer,
int domain);
extern void cs5535_mfgpt_free_timer(struct cs5535_mfgpt_timer *timer);
static inline int cs5535_mfgpt_setup_irq(struct cs5535_mfgpt_timer *timer,
int cmp, int *irq)
{
return cs5535_mfgpt_set_irq(timer, cmp, irq, 1);
}
static inline int cs5535_mfgpt_release_irq(struct cs5535_mfgpt_timer *timer,
int cmp, int *irq)
{
return cs5535_mfgpt_set_irq(timer, cmp, irq, 0);
}
#endif