u-boot/arch/arm/mach-nexell/timer.c
Stefan Bosch 95e9a8e2cb arm: add mach-nexell (all files except header files)
Changes in relation to FriendlyARM's U-Boot nanopi2-v2016.01:
- SPL not supported yet --> no spl-directory in arch/arm/mach-nexell.
  Appropriate line in Makefile removed.
- clock.c: 'section(".data")' added to declaration of clk_periphs[] and
  core_hz.
- Kconfig: Changes to have a structure like in mach-bcm283x/Kconfig,
  e.g. "config ..." entries moved from other Kconfig.
- timer.c: 'section(".data")' added to declaration of timestamp and
  lastdec.
- arch/arm/mach-nexell/serial.c removed because this is for the UARTs
  of the S5P6818 SoC which is not supported yet. S5P4418 UARTs are
  different, here the (existing) PL011-code is used.
- '#ifdef CONFIG...' changed to 'if (IS_ENABLED(CONFIG...))' where
  possible (and similar).

Signed-off-by: Stefan Bosch <stefan_b@posteo.net>
2020-07-29 08:43:40 -04:00

299 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2016 Nexell
* Hyunseok, Jung <hsjung@nexell.co.kr>
*/
#include <common.h>
#include <log.h>
#include <asm/io.h>
#include <asm/arch/nexell.h>
#include <asm/arch/clk.h>
#if defined(CONFIG_ARCH_S5P4418)
#include <asm/arch/reset.h>
#endif
#if (CONFIG_TIMER_SYS_TICK_CH > 3)
#error Not support timer channel. Please use "0~3" channels.
#endif
/* global variables to save timer count
*
* Section ".data" must be used because BSS is not available before relocation,
* in board_init_f(), respectively! I.e. global variables can not be used!
*/
static unsigned long timestamp __attribute__ ((section(".data")));
static unsigned long lastdec __attribute__ ((section(".data")));
static int timerinit __attribute__ ((section(".data")));
/* macro to hw timer tick config */
static long TIMER_FREQ = 1000000;
static long TIMER_HZ = 1000000 / CONFIG_SYS_HZ;
static long TIMER_COUNT = 0xFFFFFFFF;
#define REG_TCFG0 (0x00)
#define REG_TCFG1 (0x04)
#define REG_TCON (0x08)
#define REG_TCNTB0 (0x0C)
#define REG_TCMPB0 (0x10)
#define REG_TCNT0 (0x14)
#define REG_CSTAT (0x44)
#define TCON_BIT_AUTO (1 << 3)
#define TCON_BIT_INVT (1 << 2)
#define TCON_BIT_UP (1 << 1)
#define TCON_BIT_RUN (1 << 0)
#define TCFG0_BIT_CH(ch) ((ch) == 0 || (ch) == 1 ? 0 : 8)
#define TCFG1_BIT_CH(ch) ((ch) * 4)
#define TCON_BIT_CH(ch) ((ch) ? (ch) * 4 + 4 : 0)
#define TINT_CH(ch) (ch)
#define TINT_CSTAT_BIT_CH(ch) ((ch) + 5)
#define TINT_CSTAT_MASK (0x1F)
#define TIMER_TCNT_OFFS (0xC)
void reset_timer_masked(void);
unsigned long get_timer_masked(void);
/*
* Timer HW
*/
static inline void timer_clock(void __iomem *base, int ch, int mux, int scl)
{
u32 val = readl(base + REG_TCFG0) & ~(0xFF << TCFG0_BIT_CH(ch));
writel(val | ((scl - 1) << TCFG0_BIT_CH(ch)), base + REG_TCFG0);
val = readl(base + REG_TCFG1) & ~(0xF << TCFG1_BIT_CH(ch));
writel(val | (mux << TCFG1_BIT_CH(ch)), base + REG_TCFG1);
}
static inline void timer_count(void __iomem *base, int ch, unsigned int cnt)
{
writel((cnt - 1), base + REG_TCNTB0 + (TIMER_TCNT_OFFS * ch));
writel((cnt - 1), base + REG_TCMPB0 + (TIMER_TCNT_OFFS * ch));
}
static inline void timer_start(void __iomem *base, int ch)
{
int on = 0;
u32 val = readl(base + REG_CSTAT) & ~(TINT_CSTAT_MASK << 5 | 0x1 << ch);
writel(val | (0x1 << TINT_CSTAT_BIT_CH(ch) | on << ch),
base + REG_CSTAT);
val = readl(base + REG_TCON) & ~(0xE << TCON_BIT_CH(ch));
writel(val | (TCON_BIT_UP << TCON_BIT_CH(ch)), base + REG_TCON);
val &= ~(TCON_BIT_UP << TCON_BIT_CH(ch));
val |= ((TCON_BIT_AUTO | TCON_BIT_RUN) << TCON_BIT_CH(ch));
writel(val, base + REG_TCON);
dmb();
}
static inline void timer_stop(void __iomem *base, int ch)
{
int on = 0;
u32 val = readl(base + REG_CSTAT) & ~(TINT_CSTAT_MASK << 5 | 0x1 << ch);
writel(val | (0x1 << TINT_CSTAT_BIT_CH(ch) | on << ch),
base + REG_CSTAT);
val = readl(base + REG_TCON) & ~(TCON_BIT_RUN << TCON_BIT_CH(ch));
writel(val, base + REG_TCON);
}
static inline unsigned long timer_read(void __iomem *base, int ch)
{
unsigned long ret;
ret = TIMER_COUNT - readl(base + REG_TCNT0 + (TIMER_TCNT_OFFS * ch));
return ret;
}
int timer_init(void)
{
struct clk *clk = NULL;
char name[16] = "pclk";
int ch = CONFIG_TIMER_SYS_TICK_CH;
unsigned long rate, tclk = 0;
unsigned long mout, thz, cmp = -1UL;
int tcnt, tscl = 0, tmux = 0;
int mux = 0, scl = 0;
void __iomem *base = (void __iomem *)PHY_BASEADDR_TIMER;
if (timerinit)
return 0;
/* get with PCLK */
clk = clk_get(name);
rate = clk_get_rate(clk);
for (mux = 0; mux < 5; mux++) {
mout = rate / (1 << mux), scl = mout / TIMER_FREQ,
thz = mout / scl;
if (!(mout % TIMER_FREQ) && 256 > scl) {
tclk = thz, tmux = mux, tscl = scl;
break;
}
if (scl > 256)
continue;
if (abs(thz - TIMER_FREQ) >= cmp)
continue;
tclk = thz, tmux = mux, tscl = scl;
cmp = abs(thz - TIMER_FREQ);
}
tcnt = tclk; /* Timer Count := 1 Mhz counting */
TIMER_FREQ = tcnt; /* Timer Count := 1 Mhz counting */
TIMER_HZ = TIMER_FREQ / CONFIG_SYS_HZ;
tcnt = TIMER_COUNT == 0xFFFFFFFF ? TIMER_COUNT + 1 : tcnt;
timer_stop(base, ch);
timer_clock(base, ch, tmux, tscl);
timer_count(base, ch, tcnt);
timer_start(base, ch);
reset_timer_masked();
timerinit = 1;
return 0;
}
void reset_timer(void)
{
reset_timer_masked();
}
unsigned long get_timer(unsigned long base)
{
long ret;
unsigned long time = get_timer_masked();
unsigned long hz = TIMER_HZ;
ret = time / hz - base;
return ret;
}
void set_timer(unsigned long t)
{
timestamp = (unsigned long)t;
}
void reset_timer_masked(void)
{
void __iomem *base = (void __iomem *)PHY_BASEADDR_TIMER;
int ch = CONFIG_TIMER_SYS_TICK_CH;
/* reset time */
/* capure current decrementer value time */
lastdec = timer_read(base, ch);
/* start "advancing" time stamp from 0 */
timestamp = 0;
}
unsigned long get_timer_masked(void)
{
void __iomem *base = (void __iomem *)PHY_BASEADDR_TIMER;
int ch = CONFIG_TIMER_SYS_TICK_CH;
unsigned long now = timer_read(base, ch); /* current tick value */
if (now >= lastdec) { /* normal mode (non roll) */
/* move stamp fordward with absolute diff ticks */
timestamp += now - lastdec;
} else {
/* we have overflow of the count down timer */
/* nts = ts + ld + (TLV - now)
* ts=old stamp, ld=time that passed before passing through -1
* (TLV-now) amount of time after passing though -1
* nts = new "advancing time stamp"...
* it could also roll and cause problems.
*/
timestamp += now + TIMER_COUNT - lastdec;
}
/* save last */
lastdec = now;
debug("now=%lu, last=%lu, timestamp=%lu\n", now, lastdec, timestamp);
return (unsigned long)timestamp;
}
void __udelay(unsigned long usec)
{
unsigned long tmo, tmp;
debug("+udelay=%ld\n", usec);
if (!timerinit)
timer_init();
/* if "big" number, spread normalization to seconds */
if (usec >= 1000) {
/* start to normalize for usec to ticks per sec */
tmo = usec / 1000;
/* find number of "ticks" to wait to achieve target */
tmo *= TIMER_FREQ;
/* finish normalize. */
tmo /= 1000;
/* else small number, don't kill it prior to HZ multiply */
} else {
tmo = usec * TIMER_FREQ;
tmo /= (1000 * 1000);
}
tmp = get_timer_masked(); /* get current timestamp */
debug("A. tmo=%ld, tmp=%ld\n", tmo, tmp);
/* if setting this fordward will roll time stamp */
if (tmp > (tmo + tmp + 1))
/* reset "advancing" timestamp to 0, set lastdec value */
reset_timer_masked();
else
/* set advancing stamp wake up time */
tmo += tmp;
debug("B. tmo=%ld, tmp=%ld\n", tmo, tmp);
/* loop till event */
do {
tmp = get_timer_masked();
} while (tmo > tmp);
debug("-udelay=%ld\n", usec);
}
void udelay_masked(unsigned long usec)
{
unsigned long tmo, endtime;
signed long diff;
/* if "big" number, spread normalization to seconds */
if (usec >= 1000) {
/* start to normalize for usec to ticks per sec */
tmo = usec / 1000;
/* find number of "ticks" to wait to achieve target */
tmo *= TIMER_FREQ;
/* finish normalize. */
tmo /= 1000;
} else { /* else small number, don't kill it prior to HZ multiply */
tmo = usec * TIMER_FREQ;
tmo /= (1000 * 1000);
}
endtime = get_timer_masked() + tmo;
do {
unsigned long now = get_timer_masked();
diff = endtime - now;
} while (diff >= 0);
}
unsigned long long get_ticks(void)
{
return get_timer_masked();
}
#if defined(CONFIG_ARCH_S5P4418)
ulong get_tbclk(void)
{
ulong tbclk = TIMER_FREQ;
return tbclk;
}
#endif