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Release 4.14 arch/powerpc/platforms/powermac/time.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Support for periodic interrupts (100 per second) and for getting
 * the current time from the RTC on Power Macintoshes.
 *
 * We use the decrementer register for our periodic interrupts.
 *
 * Paul Mackerras       August 1996.
 * Copyright (C) 1996 Paul Mackerras.
 * Copyright (C) 2003-2005 Benjamin Herrenschmidt.
 *
 */
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/pmu.h>
#include <linux/interrupt.h>
#include <linux/hardirq.h>
#include <linux/rtc.h>

#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/machdep.h>
#include <asm/time.h>
#include <asm/nvram.h>
#include <asm/smu.h>


#undef DEBUG

#ifdef DEBUG

#define DBG(x...) printk(x)
#else

#define DBG(x...)
#endif

/* Apparently the RTC stores seconds since 1 Jan 1904 */

#define RTC_OFFSET	2082844800

/*
 * Calibrate the decrementer frequency with the VIA timer 1.
 */

#define VIA_TIMER_FREQ_6	4700000	
/* time 1 frequency * 6 */

/* VIA registers */

#define RS		0x200		
/* skip between registers */

#define T1CL		(4*RS)		
/* Timer 1 ctr/latch (low 8 bits) */

#define T1CH		(5*RS)		
/* Timer 1 counter (high 8 bits) */

#define T1LL		(6*RS)		
/* Timer 1 latch (low 8 bits) */

#define T1LH		(7*RS)		
/* Timer 1 latch (high 8 bits) */

#define ACR		(11*RS)		
/* Auxiliary control register */

#define IFR		(13*RS)		
/* Interrupt flag register */

/* Bits in ACR */

#define T1MODE		0xc0		
/* Timer 1 mode */

#define T1MODE_CONT	0x40		
/*  continuous interrupts */

/* Bits in IFR and IER */

#define T1_INT		0x40		
/* Timer 1 interrupt */


long __init pmac_time_init(void) { s32 delta = 0; #ifdef CONFIG_NVRAM int dst; delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16; delta |= ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xa)) << 8; delta |= pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xb); if (delta & 0x00800000UL) delta |= 0xFF000000UL; dst = ((pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x8) & 0x80) != 0); printk("GMT Delta read from XPRAM: %d minutes, DST: %s\n", delta/60, dst ? "on" : "off"); #endif return delta; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mackerras107100.00%2100.00%
Total107100.00%2100.00%

#if defined(CONFIG_ADB_CUDA) || defined(CONFIG_ADB_PMU)
static void to_rtc_time(unsigned long now, struct rtc_time *tm) { to_tm(now, tm); tm->tm_year -= 1900; tm->tm_mon -= 1; }

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Paul Mackerras34100.00%2100.00%
Total34100.00%2100.00%

#endif #if defined(CONFIG_ADB_CUDA) || defined(CONFIG_ADB_PMU) || \ defined(CONFIG_PMAC_SMU)
static unsigned long from_rtc_time(struct rtc_time *tm) { return mktime(tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); }

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PersonTokensPropCommitsCommitProp
Paul Mackerras44100.00%2100.00%
Total44100.00%2100.00%

#endif #ifdef CONFIG_ADB_CUDA
static unsigned long cuda_get_time(void) { struct adb_request req; unsigned int now; if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0) return 0; while (!req.complete) cuda_poll(); if (req.reply_len != 7) printk(KERN_ERR "cuda_get_time: got %d byte reply\n", req.reply_len); now = (req.reply[3] << 24) + (req.reply[4] << 16) + (req.reply[5] << 8) + req.reply[6]; return ((unsigned long)now) - RTC_OFFSET; }

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PersonTokensPropCommitsCommitProp
Paul Mackerras11294.12%266.67%
Benjamin Herrenschmidt75.88%133.33%
Total119100.00%3100.00%

#define cuda_get_rtc_time(tm) to_rtc_time(cuda_get_time(), (tm))
static int cuda_set_rtc_time(struct rtc_time *tm) { unsigned int nowtime; struct adb_request req; nowtime = from_rtc_time(tm) + RTC_OFFSET; if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME, nowtime >> 24, nowtime >> 16, nowtime >> 8, nowtime) < 0) return -ENXIO; while (!req.complete) cuda_poll(); if ((req.reply_len != 3) && (req.reply_len != 7)) printk(KERN_ERR "cuda_set_rtc_time: got %d byte reply\n", req.reply_len); return 0; }

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PersonTokensPropCommitsCommitProp
Paul Mackerras105100.00%2100.00%
Total105100.00%2100.00%

#else #define cuda_get_time() 0 #define cuda_get_rtc_time(tm) #define cuda_set_rtc_time(tm) 0 #endif #ifdef CONFIG_ADB_PMU
static unsigned long pmu_get_time(void) { struct adb_request req; unsigned int now; if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0) return 0; pmu_wait_complete(&req); if (req.reply_len != 4) printk(KERN_ERR "pmu_get_time: got %d byte reply from PMU\n", req.reply_len); now = (req.reply[0] << 24) + (req.reply[1] << 16) + (req.reply[2] << 8) + req.reply[3]; return ((unsigned long)now) - RTC_OFFSET; }

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PersonTokensPropCommitsCommitProp
Paul Mackerras10693.81%266.67%
Benjamin Herrenschmidt76.19%133.33%
Total113100.00%3100.00%

#define pmu_get_rtc_time(tm) to_rtc_time(pmu_get_time(), (tm))
static int pmu_set_rtc_time(struct rtc_time *tm) { unsigned int nowtime; struct adb_request req; nowtime = from_rtc_time(tm) + RTC_OFFSET; if (pmu_request(&req, NULL, 5, PMU_SET_RTC, nowtime >> 24, nowtime >> 16, nowtime >> 8, nowtime) < 0) return -ENXIO; pmu_wait_complete(&req); if (req.reply_len != 0) printk(KERN_ERR "pmu_set_rtc_time: %d byte reply from PMU\n", req.reply_len); return 0; }

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Paul Mackerras89100.00%3100.00%
Total89100.00%3100.00%

#else #define pmu_get_time() 0 #define pmu_get_rtc_time(tm) #define pmu_set_rtc_time(tm) 0 #endif #ifdef CONFIG_PMAC_SMU
static unsigned long smu_get_time(void) { struct rtc_time tm; if (smu_get_rtc_time(&tm, 1)) return 0; return from_rtc_time(&tm); }

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PersonTokensPropCommitsCommitProp
Paul Mackerras33100.00%2100.00%
Total33100.00%2100.00%

#else #define smu_get_time() 0 #define smu_get_rtc_time(tm, spin) #define smu_set_rtc_time(tm, spin) 0 #endif /* Can't be __init, it's called when suspending and resuming */
unsigned long pmac_get_boot_time(void) { /* Get the time from the RTC, used only at boot time */ switch (sys_ctrler) { case SYS_CTRLER_CUDA: return cuda_get_time(); case SYS_CTRLER_PMU: return pmu_get_time(); case SYS_CTRLER_SMU: return smu_get_time(); default: return 0; } }

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PersonTokensPropCommitsCommitProp
Paul Mackerras40100.00%1100.00%
Total40100.00%1100.00%


void pmac_get_rtc_time(struct rtc_time *tm) { /* Get the time from the RTC, used only at boot time */ switch (sys_ctrler) { case SYS_CTRLER_CUDA: cuda_get_rtc_time(tm); break; case SYS_CTRLER_PMU: pmu_get_rtc_time(tm); break; case SYS_CTRLER_SMU: smu_get_rtc_time(tm, 1); break; default: ; } }

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PersonTokensPropCommitsCommitProp
Paul Mackerras48100.00%2100.00%
Total48100.00%2100.00%


int pmac_set_rtc_time(struct rtc_time *tm) { switch (sys_ctrler) { case SYS_CTRLER_CUDA: return cuda_set_rtc_time(tm); case SYS_CTRLER_PMU: return pmu_set_rtc_time(tm); case SYS_CTRLER_SMU: return smu_set_rtc_time(tm, 1); default: return -ENODEV; } }

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PersonTokensPropCommitsCommitProp
Paul Mackerras50100.00%3100.00%
Total50100.00%3100.00%

#ifdef CONFIG_PPC32 /* * Calibrate the decrementer register using VIA timer 1. * This is used both on powermacs and CHRP machines. */
int __init via_calibrate_decr(void) { struct device_node *vias; volatile unsigned char __iomem *via; int count = VIA_TIMER_FREQ_6 / 100; unsigned int dstart, dend; struct resource rsrc; vias = of_find_node_by_name(NULL, "via-cuda"); if (vias == NULL) vias = of_find_node_by_name(NULL, "via-pmu"); if (vias == NULL) vias = of_find_node_by_name(NULL, "via"); if (vias == NULL || of_address_to_resource(vias, 0, &rsrc)) { of_node_put(vias); return 0; } of_node_put(vias); via = ioremap(rsrc.start, resource_size(&rsrc)); if (via == NULL) { printk(KERN_ERR "Failed to map VIA for timer calibration !\n"); return 0; } /* set timer 1 for continuous interrupts */ out_8(&via[ACR], (via[ACR] & ~T1MODE) | T1MODE_CONT); /* set the counter to a small value */ out_8(&via[T1CH], 2); /* set the latch to `count' */ out_8(&via[T1LL], count); out_8(&via[T1LH], count >> 8); /* wait until it hits 0 */ while ((in_8(&via[IFR]) & T1_INT) == 0) ; dstart = get_dec(); /* clear the interrupt & wait until it hits 0 again */ in_8(&via[T1CL]); while ((in_8(&via[IFR]) & T1_INT) == 0) ; dend = get_dec(); ppc_tb_freq = (dstart - dend) * 100 / 6; iounmap(via); return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mackerras21678.55%240.00%
Benjamin Herrenschmidt4014.55%120.00%
Nicolas Palix155.45%120.00%
Joe Perches41.45%120.00%
Total275100.00%5100.00%

#endif /* * Query the OF and get the decr frequency. */
void __init pmac_calibrate_decr(void) { generic_calibrate_decr(); #ifdef CONFIG_PPC32 /* We assume MacRISC2 machines have correct device-tree * calibration. That's better since the VIA itself seems * to be slightly off. --BenH */ if (!of_machine_is_compatible("MacRISC2") && !of_machine_is_compatible("MacRISC3") && !of_machine_is_compatible("MacRISC4")) if (via_calibrate_decr()) return; /* Special case: QuickSilver G4s seem to have a badly calibrated * timebase-frequency in OF, VIA is much better on these. We should * probably implement calibration based on the KL timer on these * machines anyway... -BenH */ if (of_machine_is_compatible("PowerMac3,5")) if (via_calibrate_decr()) return; #endif }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mackerras5392.98%266.67%
Grant C. Likely47.02%133.33%
Total57100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Paul Mackerras129492.17%642.86%
Benjamin Herrenschmidt543.85%214.29%
Tony Breeds191.35%17.14%
Nicolas Palix151.07%17.14%
Johannes Berg130.93%17.14%
Joe Perches40.28%17.14%
Grant C. Likely40.28%17.14%
Greg Kroah-Hartman10.07%17.14%
Total1404100.00%14100.00%
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