linux/arch/m68k/mac/misc.c
Finn Thain 75a23850cd m68k/mac: Fix compiler warning in via_read_time()
The algorithm described in the comment compares two reads from the RTC but
the code actually reads once and compares the result to an uninitialized
value. This causes the compiler to warn, "last_result maybe used
uninitialized". Make the code match the comment, fix the warning and
perhaps improve reliability. Tested on a Quadra 700.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-10-24 21:00:34 +02:00

773 lines
17 KiB
C

/*
* Miscellaneous Mac68K-specific stuff
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/mm.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/pmu.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/rtc.h>
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/setup.h>
#include <asm/macintosh.h>
#include <asm/mac_via.h>
#include <asm/mac_oss.h>
#define BOOTINFO_COMPAT_1_0
#include <asm/bootinfo.h>
#include <asm/machdep.h>
/* Offset between Unix time (1970-based) and Mac time (1904-based) */
#define RTC_OFFSET 2082844800
static void (*rom_reset)(void);
#ifdef CONFIG_ADB_CUDA
static long cuda_read_time(void)
{
struct adb_request req;
long time;
if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
return 0;
while (!req.complete)
cuda_poll();
time = (req.reply[3] << 24) | (req.reply[4] << 16)
| (req.reply[5] << 8) | req.reply[6];
return time - RTC_OFFSET;
}
static void cuda_write_time(long data)
{
struct adb_request req;
data += RTC_OFFSET;
if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
(data >> 24) & 0xFF, (data >> 16) & 0xFF,
(data >> 8) & 0xFF, data & 0xFF) < 0)
return;
while (!req.complete)
cuda_poll();
}
static __u8 cuda_read_pram(int offset)
{
struct adb_request req;
if (cuda_request(&req, NULL, 4, CUDA_PACKET, CUDA_GET_PRAM,
(offset >> 8) & 0xFF, offset & 0xFF) < 0)
return 0;
while (!req.complete)
cuda_poll();
return req.reply[3];
}
static void cuda_write_pram(int offset, __u8 data)
{
struct adb_request req;
if (cuda_request(&req, NULL, 5, CUDA_PACKET, CUDA_SET_PRAM,
(offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
return;
while (!req.complete)
cuda_poll();
}
#else
#define cuda_read_time() 0
#define cuda_write_time(n)
#define cuda_read_pram NULL
#define cuda_write_pram NULL
#endif
#ifdef CONFIG_ADB_PMU68K
static long pmu_read_time(void)
{
struct adb_request req;
long time;
if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
return 0;
while (!req.complete)
pmu_poll();
time = (req.reply[1] << 24) | (req.reply[2] << 16)
| (req.reply[3] << 8) | req.reply[4];
return time - RTC_OFFSET;
}
static void pmu_write_time(long data)
{
struct adb_request req;
data += RTC_OFFSET;
if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
(data >> 24) & 0xFF, (data >> 16) & 0xFF,
(data >> 8) & 0xFF, data & 0xFF) < 0)
return;
while (!req.complete)
pmu_poll();
}
static __u8 pmu_read_pram(int offset)
{
struct adb_request req;
if (pmu_request(&req, NULL, 3, PMU_READ_NVRAM,
(offset >> 8) & 0xFF, offset & 0xFF) < 0)
return 0;
while (!req.complete)
pmu_poll();
return req.reply[3];
}
static void pmu_write_pram(int offset, __u8 data)
{
struct adb_request req;
if (pmu_request(&req, NULL, 4, PMU_WRITE_NVRAM,
(offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
return;
while (!req.complete)
pmu_poll();
}
#else
#define pmu_read_time() 0
#define pmu_write_time(n)
#define pmu_read_pram NULL
#define pmu_write_pram NULL
#endif
#if 0 /* def CONFIG_ADB_MACIISI */
extern int maciisi_request(struct adb_request *req,
void (*done)(struct adb_request *), int nbytes, ...);
static long maciisi_read_time(void)
{
struct adb_request req;
long time;
if (maciisi_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME))
return 0;
time = (req.reply[3] << 24) | (req.reply[4] << 16)
| (req.reply[5] << 8) | req.reply[6];
return time - RTC_OFFSET;
}
static void maciisi_write_time(long data)
{
struct adb_request req;
data += RTC_OFFSET;
maciisi_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
(data >> 24) & 0xFF, (data >> 16) & 0xFF,
(data >> 8) & 0xFF, data & 0xFF);
}
static __u8 maciisi_read_pram(int offset)
{
struct adb_request req;
if (maciisi_request(&req, NULL, 4, CUDA_PACKET, CUDA_GET_PRAM,
(offset >> 8) & 0xFF, offset & 0xFF))
return 0;
return req.reply[3];
}
static void maciisi_write_pram(int offset, __u8 data)
{
struct adb_request req;
maciisi_request(&req, NULL, 5, CUDA_PACKET, CUDA_SET_PRAM,
(offset >> 8) & 0xFF, offset & 0xFF, data);
}
#else
#define maciisi_read_time() 0
#define maciisi_write_time(n)
#define maciisi_read_pram NULL
#define maciisi_write_pram NULL
#endif
/*
* VIA PRAM/RTC access routines
*
* Must be called with interrupts disabled and
* the RTC should be enabled.
*/
static __u8 via_pram_readbyte(void)
{
int i,reg;
__u8 data;
reg = via1[vBufB] & ~VIA1B_vRTCClk;
/* Set the RTC data line to be an input. */
via1[vDirB] &= ~VIA1B_vRTCData;
/* The bits of the byte come out in MSB order */
data = 0;
for (i = 0 ; i < 8 ; i++) {
via1[vBufB] = reg;
via1[vBufB] = reg | VIA1B_vRTCClk;
data = (data << 1) | (via1[vBufB] & VIA1B_vRTCData);
}
/* Return RTC data line to output state */
via1[vDirB] |= VIA1B_vRTCData;
return data;
}
static void via_pram_writebyte(__u8 data)
{
int i,reg,bit;
reg = via1[vBufB] & ~(VIA1B_vRTCClk | VIA1B_vRTCData);
/* The bits of the byte go in in MSB order */
for (i = 0 ; i < 8 ; i++) {
bit = data & 0x80? 1 : 0;
data <<= 1;
via1[vBufB] = reg | bit;
via1[vBufB] = reg | bit | VIA1B_vRTCClk;
}
}
/*
* Execute a VIA PRAM/RTC command. For read commands
* data should point to a one-byte buffer for the
* resulting data. For write commands it should point
* to the data byte to for the command.
*
* This function disables all interrupts while running.
*/
static void via_pram_command(int command, __u8 *data)
{
unsigned long flags;
int is_read;
local_irq_save(flags);
/* Enable the RTC and make sure the strobe line is high */
via1[vBufB] = (via1[vBufB] | VIA1B_vRTCClk) & ~VIA1B_vRTCEnb;
if (command & 0xFF00) { /* extended (two-byte) command */
via_pram_writebyte((command & 0xFF00) >> 8);
via_pram_writebyte(command & 0xFF);
is_read = command & 0x8000;
} else { /* one-byte command */
via_pram_writebyte(command);
is_read = command & 0x80;
}
if (is_read) {
*data = via_pram_readbyte();
} else {
via_pram_writebyte(*data);
}
/* All done, disable the RTC */
via1[vBufB] |= VIA1B_vRTCEnb;
local_irq_restore(flags);
}
static __u8 via_read_pram(int offset)
{
return 0;
}
static void via_write_pram(int offset, __u8 data)
{
}
/*
* Return the current time in seconds since January 1, 1904.
*
* This only works on machines with the VIA-based PRAM/RTC, which
* is basically any machine with Mac II-style ADB.
*/
static long via_read_time(void)
{
union {
__u8 cdata[4];
long idata;
} result, last_result;
int count = 1;
via_pram_command(0x81, &last_result.cdata[3]);
via_pram_command(0x85, &last_result.cdata[2]);
via_pram_command(0x89, &last_result.cdata[1]);
via_pram_command(0x8D, &last_result.cdata[0]);
/*
* The NetBSD guys say to loop until you get the same reading
* twice in a row.
*/
while (1) {
via_pram_command(0x81, &result.cdata[3]);
via_pram_command(0x85, &result.cdata[2]);
via_pram_command(0x89, &result.cdata[1]);
via_pram_command(0x8D, &result.cdata[0]);
if (result.idata == last_result.idata)
return result.idata - RTC_OFFSET;
if (++count > 10)
break;
last_result.idata = result.idata;
}
pr_err("via_read_time: failed to read a stable value; "
"got 0x%08lx then 0x%08lx\n",
last_result.idata, result.idata);
return 0;
}
/*
* Set the current time to a number of seconds since January 1, 1904.
*
* This only works on machines with the VIA-based PRAM/RTC, which
* is basically any machine with Mac II-style ADB.
*/
static void via_write_time(long time)
{
union {
__u8 cdata[4];
long idata;
} data;
__u8 temp;
/* Clear the write protect bit */
temp = 0x55;
via_pram_command(0x35, &temp);
data.idata = time + RTC_OFFSET;
via_pram_command(0x01, &data.cdata[3]);
via_pram_command(0x05, &data.cdata[2]);
via_pram_command(0x09, &data.cdata[1]);
via_pram_command(0x0D, &data.cdata[0]);
/* Set the write protect bit */
temp = 0xD5;
via_pram_command(0x35, &temp);
}
static void via_shutdown(void)
{
if (rbv_present) {
via2[rBufB] &= ~0x04;
} else {
/* Direction of vDirB is output */
via2[vDirB] |= 0x04;
/* Send a value of 0 on that line */
via2[vBufB] &= ~0x04;
mdelay(1000);
}
}
/*
* FIXME: not sure how this is supposed to work exactly...
*/
static void oss_shutdown(void)
{
oss->rom_ctrl = OSS_POWEROFF;
}
#ifdef CONFIG_ADB_CUDA
static void cuda_restart(void)
{
struct adb_request req;
if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_RESET_SYSTEM) < 0)
return;
while (!req.complete)
cuda_poll();
}
static void cuda_shutdown(void)
{
struct adb_request req;
if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_POWERDOWN) < 0)
return;
while (!req.complete)
cuda_poll();
}
#endif /* CONFIG_ADB_CUDA */
#ifdef CONFIG_ADB_PMU68K
void pmu_restart(void)
{
struct adb_request req;
if (pmu_request(&req, NULL,
2, PMU_SET_INTR_MASK, PMU_INT_ADB|PMU_INT_TICK) < 0)
return;
while (!req.complete)
pmu_poll();
if (pmu_request(&req, NULL, 1, PMU_RESET) < 0)
return;
while (!req.complete)
pmu_poll();
}
void pmu_shutdown(void)
{
struct adb_request req;
if (pmu_request(&req, NULL,
2, PMU_SET_INTR_MASK, PMU_INT_ADB|PMU_INT_TICK) < 0)
return;
while (!req.complete)
pmu_poll();
if (pmu_request(&req, NULL, 5, PMU_SHUTDOWN, 'M', 'A', 'T', 'T') < 0)
return;
while (!req.complete)
pmu_poll();
}
#endif
/*
*-------------------------------------------------------------------
* Below this point are the generic routines; they'll dispatch to the
* correct routine for the hardware on which we're running.
*-------------------------------------------------------------------
*/
void mac_pram_read(int offset, __u8 *buffer, int len)
{
__u8 (*func)(int);
int i;
switch(macintosh_config->adb_type) {
case MAC_ADB_IISI:
func = maciisi_read_pram; break;
case MAC_ADB_PB1:
case MAC_ADB_PB2:
func = pmu_read_pram; break;
case MAC_ADB_CUDA:
func = cuda_read_pram; break;
default:
func = via_read_pram;
}
if (!func)
return;
for (i = 0 ; i < len ; i++) {
buffer[i] = (*func)(offset++);
}
}
void mac_pram_write(int offset, __u8 *buffer, int len)
{
void (*func)(int, __u8);
int i;
switch(macintosh_config->adb_type) {
case MAC_ADB_IISI:
func = maciisi_write_pram; break;
case MAC_ADB_PB1:
case MAC_ADB_PB2:
func = pmu_write_pram; break;
case MAC_ADB_CUDA:
func = cuda_write_pram; break;
default:
func = via_write_pram;
}
if (!func)
return;
for (i = 0 ; i < len ; i++) {
(*func)(offset++, buffer[i]);
}
}
void mac_poweroff(void)
{
/*
* MAC_ADB_IISI may need to be moved up here if it doesn't actually
* work using the ADB packet method. --David Kilzer
*/
if (oss_present) {
oss_shutdown();
} else if (macintosh_config->adb_type == MAC_ADB_II) {
via_shutdown();
#ifdef CONFIG_ADB_CUDA
} else if (macintosh_config->adb_type == MAC_ADB_CUDA) {
cuda_shutdown();
#endif
#ifdef CONFIG_ADB_PMU68K
} else if (macintosh_config->adb_type == MAC_ADB_PB1
|| macintosh_config->adb_type == MAC_ADB_PB2) {
pmu_shutdown();
#endif
}
local_irq_enable();
printk("It is now safe to turn off your Macintosh.\n");
while(1);
}
void mac_reset(void)
{
if (macintosh_config->adb_type == MAC_ADB_II) {
unsigned long flags;
/* need ROMBASE in booter */
/* indeed, plus need to MAP THE ROM !! */
if (mac_bi_data.rombase == 0)
mac_bi_data.rombase = 0x40800000;
/* works on some */
rom_reset = (void *) (mac_bi_data.rombase + 0xa);
if (macintosh_config->ident == MAC_MODEL_SE30) {
/*
* MSch: Machines known to crash on ROM reset ...
*/
} else {
local_irq_save(flags);
rom_reset();
local_irq_restore(flags);
}
#ifdef CONFIG_ADB_CUDA
} else if (macintosh_config->adb_type == MAC_ADB_CUDA) {
cuda_restart();
#endif
#ifdef CONFIG_ADB_PMU68K
} else if (macintosh_config->adb_type == MAC_ADB_PB1
|| macintosh_config->adb_type == MAC_ADB_PB2) {
pmu_restart();
#endif
} else if (CPU_IS_030) {
/* 030-specific reset routine. The idea is general, but the
* specific registers to reset are '030-specific. Until I
* have a non-030 machine, I can't test anything else.
* -- C. Scott Ananian <cananian@alumni.princeton.edu>
*/
unsigned long rombase = 0x40000000;
/* make a 1-to-1 mapping, using the transparent tran. reg. */
unsigned long virt = (unsigned long) mac_reset;
unsigned long phys = virt_to_phys(mac_reset);
unsigned long addr = (phys&0xFF000000)|0x8777;
unsigned long offset = phys-virt;
local_irq_disable(); /* lets not screw this up, ok? */
__asm__ __volatile__(".chip 68030\n\t"
"pmove %0,%/tt0\n\t"
".chip 68k"
: : "m" (addr));
/* Now jump to physical address so we can disable MMU */
__asm__ __volatile__(
".chip 68030\n\t"
"lea %/pc@(1f),%/a0\n\t"
"addl %0,%/a0\n\t"/* fixup target address and stack ptr */
"addl %0,%/sp\n\t"
"pflusha\n\t"
"jmp %/a0@\n\t" /* jump into physical memory */
"0:.long 0\n\t" /* a constant zero. */
/* OK. Now reset everything and jump to reset vector. */
"1:\n\t"
"lea %/pc@(0b),%/a0\n\t"
"pmove %/a0@, %/tc\n\t" /* disable mmu */
"pmove %/a0@, %/tt0\n\t" /* disable tt0 */
"pmove %/a0@, %/tt1\n\t" /* disable tt1 */
"movel #0, %/a0\n\t"
"movec %/a0, %/vbr\n\t" /* clear vector base register */
"movec %/a0, %/cacr\n\t" /* disable caches */
"movel #0x0808,%/a0\n\t"
"movec %/a0, %/cacr\n\t" /* flush i&d caches */
"movew #0x2700,%/sr\n\t" /* set up status register */
"movel %1@(0x0),%/a0\n\t"/* load interrupt stack pointer */
"movec %/a0, %/isp\n\t"
"movel %1@(0x4),%/a0\n\t" /* load reset vector */
"reset\n\t" /* reset external devices */
"jmp %/a0@\n\t" /* jump to the reset vector */
".chip 68k"
: : "r" (offset), "a" (rombase) : "a0");
}
/* should never get here */
local_irq_enable();
printk ("Restart failed. Please restart manually.\n");
while(1);
}
/*
* This function translates seconds since 1970 into a proper date.
*
* Algorithm cribbed from glibc2.1, __offtime().
*/
#define SECS_PER_MINUTE (60)
#define SECS_PER_HOUR (SECS_PER_MINUTE * 60)
#define SECS_PER_DAY (SECS_PER_HOUR * 24)
static void unmktime(unsigned long time, long offset,
int *yearp, int *monp, int *dayp,
int *hourp, int *minp, int *secp)
{
/* How many days come before each month (0-12). */
static const unsigned short int __mon_yday[2][13] =
{
/* Normal years. */
{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
/* Leap years. */
{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
};
long int days, rem, y, wday, yday;
const unsigned short int *ip;
days = time / SECS_PER_DAY;
rem = time % SECS_PER_DAY;
rem += offset;
while (rem < 0) {
rem += SECS_PER_DAY;
--days;
}
while (rem >= SECS_PER_DAY) {
rem -= SECS_PER_DAY;
++days;
}
*hourp = rem / SECS_PER_HOUR;
rem %= SECS_PER_HOUR;
*minp = rem / SECS_PER_MINUTE;
*secp = rem % SECS_PER_MINUTE;
/* January 1, 1970 was a Thursday. */
wday = (4 + days) % 7; /* Day in the week. Not currently used */
if (wday < 0) wday += 7;
y = 1970;
#define DIV(a, b) ((a) / (b) - ((a) % (b) < 0))
#define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
#define __isleap(year) \
((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
while (days < 0 || days >= (__isleap (y) ? 366 : 365))
{
/* Guess a corrected year, assuming 365 days per year. */
long int yg = y + days / 365 - (days % 365 < 0);
/* Adjust DAYS and Y to match the guessed year. */
days -= ((yg - y) * 365
+ LEAPS_THRU_END_OF (yg - 1)
- LEAPS_THRU_END_OF (y - 1));
y = yg;
}
*yearp = y - 1900;
yday = days; /* day in the year. Not currently used. */
ip = __mon_yday[__isleap(y)];
for (y = 11; days < (long int) ip[y]; --y)
continue;
days -= ip[y];
*monp = y;
*dayp = days + 1; /* day in the month */
return;
}
/*
* Read/write the hardware clock.
*/
int mac_hwclk(int op, struct rtc_time *t)
{
unsigned long now;
if (!op) { /* read */
switch (macintosh_config->adb_type) {
case MAC_ADB_II:
case MAC_ADB_IOP:
now = via_read_time();
break;
case MAC_ADB_IISI:
now = maciisi_read_time();
break;
case MAC_ADB_PB1:
case MAC_ADB_PB2:
now = pmu_read_time();
break;
case MAC_ADB_CUDA:
now = cuda_read_time();
break;
default:
now = 0;
}
t->tm_wday = 0;
unmktime(now, 0,
&t->tm_year, &t->tm_mon, &t->tm_mday,
&t->tm_hour, &t->tm_min, &t->tm_sec);
#if 0
printk("mac_hwclk: read %04d-%02d-%-2d %02d:%02d:%02d\n",
t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
t->tm_hour, t->tm_min, t->tm_sec);
#endif
} else { /* write */
#if 0
printk("mac_hwclk: tried to write %04d-%02d-%-2d %02d:%02d:%02d\n",
t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
t->tm_hour, t->tm_min, t->tm_sec);
#endif
now = mktime(t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
t->tm_hour, t->tm_min, t->tm_sec);
switch (macintosh_config->adb_type) {
case MAC_ADB_II:
case MAC_ADB_IOP:
via_write_time(now);
break;
case MAC_ADB_CUDA:
cuda_write_time(now);
break;
case MAC_ADB_PB1:
case MAC_ADB_PB2:
pmu_write_time(now);
break;
case MAC_ADB_IISI:
maciisi_write_time(now);
}
}
return 0;
}
/*
* Set minutes/seconds in the hardware clock
*/
int mac_set_clock_mmss (unsigned long nowtime)
{
struct rtc_time now;
mac_hwclk(0, &now);
now.tm_sec = nowtime % 60;
now.tm_min = (nowtime / 60) % 60;
mac_hwclk(1, &now);
return 0;
}