alpha: fix RTC on marvel

Unlike other alphas, marvel doesn't have real PC-style CMOS clock hardware
- RTC accesses are emulated via PAL calls.  Unfortunately, for unknown
reason these calls work only on CPU #0.  So current implementation for
arbitrary CPU makes CMOS_READ/WRITE to be executed on CPU #0 via IPI.
However, for obvious reason this doesn't work with standard
get/set_rtc_time() functions, where a bunch of CMOS accesses is done with
disabled interrupts.

Solved by making the IPI calls for entire get/set_rtc_time() functions,
not for individual CMOS accesses.  Which is also a lot more effective
performance-wise.

The patch is largely based on the code from Jay Estabrook.
My changes:
- tweak asm-generic/rtc.h by adding a couple of #defines to
  avoid a massive code duplication in arch/alpha/include/asm/rtc.h;
- sys_marvel.c: fix get/set_rtc_time() return values (Jay's FIXMEs).

NOTE: this fixes *only* LIB_RTC drivers.  Legacy (CONFIG_RTC) driver
wont't work on marvel.  Actually I think that we should just disable
CONFIG_RTC on alpha (maybe in 2.6.30?), like most other arches - AFAIK,
all modern distributions use LIB_RTC anyway.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ivan Kokshaysky 2009-01-15 13:51:19 -08:00 committed by Linus Torvalds
parent 2f88d151cb
commit 5f7dc5d750
9 changed files with 98 additions and 17 deletions

View File

@ -21,6 +21,7 @@ struct pci_dev;
struct pci_ops;
struct pci_controller;
struct _alpha_agp_info;
struct rtc_time;
struct alpha_machine_vector
{
@ -94,6 +95,9 @@ struct alpha_machine_vector
struct _alpha_agp_info *(*agp_info)(void);
unsigned int (*rtc_get_time)(struct rtc_time *);
int (*rtc_set_time)(struct rtc_time *);
const char *vector_name;
/* NUMA information */

View File

@ -1,9 +1,15 @@
#ifndef _ALPHA_RTC_H
#define _ALPHA_RTC_H
/*
* Alpha uses the default access methods for the RTC.
*/
#if defined(CONFIG_ALPHA_GENERIC)
# define get_rtc_time alpha_mv.rtc_get_time
# define set_rtc_time alpha_mv.rtc_set_time
#else
# if defined(CONFIG_ALPHA_MARVEL) && defined(CONFIG_SMP)
# define get_rtc_time marvel_get_rtc_time
# define set_rtc_time marvel_set_rtc_time
# endif
#endif
#include <asm-generic/rtc.h>

View File

@ -658,16 +658,8 @@ __marvel_rtc_io(u8 b, unsigned long addr, int write)
rtc_access.data = bcd2bin(b);
rtc_access.function = 0x48 + !write; /* GET/PUT_TOY */
#ifdef CONFIG_SMP
if (smp_processor_id() != boot_cpuid)
smp_call_function_single(boot_cpuid,
__marvel_access_rtc,
&rtc_access, 1);
else
__marvel_access_rtc(&rtc_access);
#else
__marvel_access_rtc(&rtc_access);
#endif
ret = bin2bcd(rtc_access.data);
break;

View File

@ -40,7 +40,10 @@
#define CAT1(x,y) x##y
#define CAT(x,y) CAT1(x,y)
#define DO_DEFAULT_RTC .rtc_port = 0x70
#define DO_DEFAULT_RTC \
.rtc_port = 0x70, \
.rtc_get_time = common_get_rtc_time, \
.rtc_set_time = common_set_rtc_time
#define DO_EV4_MMU \
.max_asn = EV4_MAX_ASN, \

View File

@ -145,6 +145,8 @@ extern void smp_percpu_timer_interrupt(struct pt_regs *);
extern irqreturn_t timer_interrupt(int irq, void *dev);
extern void common_init_rtc(void);
extern unsigned long est_cycle_freq;
extern unsigned int common_get_rtc_time(struct rtc_time *time);
extern int common_set_rtc_time(struct rtc_time *time);
/* smc37c93x.c */
extern void SMC93x_Init(void);

View File

@ -261,6 +261,8 @@ struct alpha_machine_vector jensen_mv __initmv = {
.machine_check = jensen_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.rtc_port = 0x170,
.rtc_get_time = common_get_rtc_time,
.rtc_set_time = common_set_rtc_time,
.nr_irqs = 16,
.device_interrupt = jensen_device_interrupt,

View File

@ -23,6 +23,7 @@
#include <asm/hwrpb.h>
#include <asm/tlbflush.h>
#include <asm/vga.h>
#include <asm/rtc.h>
#include "proto.h"
#include "err_impl.h"
@ -426,6 +427,57 @@ marvel_init_rtc(void)
init_rtc_irq();
}
struct marvel_rtc_time {
struct rtc_time *time;
int retval;
};
#ifdef CONFIG_SMP
static void
smp_get_rtc_time(void *data)
{
struct marvel_rtc_time *mrt = data;
mrt->retval = __get_rtc_time(mrt->time);
}
static void
smp_set_rtc_time(void *data)
{
struct marvel_rtc_time *mrt = data;
mrt->retval = __set_rtc_time(mrt->time);
}
#endif
static unsigned int
marvel_get_rtc_time(struct rtc_time *time)
{
#ifdef CONFIG_SMP
struct marvel_rtc_time mrt;
if (smp_processor_id() != boot_cpuid) {
mrt.time = time;
smp_call_function_single(boot_cpuid, smp_get_rtc_time, &mrt, 1);
return mrt.retval;
}
#endif
return __get_rtc_time(time);
}
static int
marvel_set_rtc_time(struct rtc_time *time)
{
#ifdef CONFIG_SMP
struct marvel_rtc_time mrt;
if (smp_processor_id() != boot_cpuid) {
mrt.time = time;
smp_call_function_single(boot_cpuid, smp_set_rtc_time, &mrt, 1);
return mrt.retval;
}
#endif
return __set_rtc_time(time);
}
static void
marvel_smp_callin(void)
{
@ -466,7 +518,9 @@ marvel_smp_callin(void)
struct alpha_machine_vector marvel_ev7_mv __initmv = {
.vector_name = "MARVEL/EV7",
DO_EV7_MMU,
DO_DEFAULT_RTC,
.rtc_port = 0x70,
.rtc_get_time = marvel_get_rtc_time,
.rtc_set_time = marvel_set_rtc_time,
DO_MARVEL_IO,
.machine_check = marvel_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,

View File

@ -46,6 +46,7 @@
#include <asm/io.h>
#include <asm/hwrpb.h>
#include <asm/8253pit.h>
#include <asm/rtc.h>
#include <linux/mc146818rtc.h>
#include <linux/time.h>
@ -180,6 +181,15 @@ common_init_rtc(void)
init_rtc_irq();
}
unsigned int common_get_rtc_time(struct rtc_time *time)
{
return __get_rtc_time(time);
}
int common_set_rtc_time(struct rtc_time *time)
{
return __set_rtc_time(time);
}
/* Validate a computed cycle counter result against the known bounds for
the given processor core. There's too much brokenness in the way of

View File

@ -42,7 +42,7 @@ static inline unsigned char rtc_is_updating(void)
return uip;
}
static inline unsigned int get_rtc_time(struct rtc_time *time)
static inline unsigned int __get_rtc_time(struct rtc_time *time)
{
unsigned char ctrl;
unsigned long flags;
@ -108,8 +108,12 @@ static inline unsigned int get_rtc_time(struct rtc_time *time)
return RTC_24H;
}
#ifndef get_rtc_time
#define get_rtc_time __get_rtc_time
#endif
/* Set the current date and time in the real time clock. */
static inline int set_rtc_time(struct rtc_time *time)
static inline int __set_rtc_time(struct rtc_time *time)
{
unsigned long flags;
unsigned char mon, day, hrs, min, sec;
@ -190,11 +194,15 @@ static inline int set_rtc_time(struct rtc_time *time)
return 0;
}
#ifndef set_rtc_time
#define set_rtc_time __set_rtc_time
#endif
static inline unsigned int get_rtc_ss(void)
{
struct rtc_time h;
get_rtc_time(&h);
__get_rtc_time(&h);
return h.tm_sec;
}