arch: m68k: Introduce trivial PIT based timer

The QEMU emulation of m68k does not support DMA timer, the only
timer that is supported is the PIT timer. Implement trivial PIT
timer support for m68k.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

diff --git a/arch/m68k/include/asm/immap.h b/arch/m68k/include/asm/immap.h
index 3b515fe2c65d3d95180036a89c8d4ebb14ee7131..aafa4f40cb35bde075d8d0169c6dfeb8a20b855f 100644 (file)
--- a/arch/m68k/include/asm/immap.h
+++ b/arch/m68k/include/asm/immap.h
@@ -25,6 +25,8 @@
 #define CFG_SYS_TMRINTR_PEND           (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (6)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)
@@ -47,6 +49,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (0x1E)          /* Level must include inorder to work */
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)
@@ -72,6 +76,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (MCFSIM_ICR_AUTOVEC | MCFSIM_ICR_LEVEL7 | MCFSIM_ICR_PRI3)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 2000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                         /* CONFIG_M5249 */
 
@@ -95,6 +101,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (MCFSIM_ICR_AUTOVEC | MCFSIM_ICR_LEVEL3 | MCFSIM_ICR_PRI3)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 2000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                         /* CONFIG_M5253 */
 
@@ -114,6 +122,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (0x1E) /* Interrupt level 3, priority 6 */
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)
@@ -139,6 +149,8 @@
 #define CFG_SYS_TMRINTR_PEND   (0)
 #define CFG_SYS_TMRINTR_PRI            (INT_ICR1_TMR3PI | INT_ICR1_TMR3IPL(5))
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                         /* CONFIG_M5272 */
 
@@ -161,6 +173,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (0x1E)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                         /* CONFIG_M5275 */
 
@@ -183,6 +197,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (0x1E)          /* Level must include inorder to work */
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                         /* CONFIG_M5282 */
 
@@ -207,6 +223,8 @@
 #define CFG_SYS_TMRINTR_PRI          (MCFSIM_ICR_AUTOVEC | \
                                        MCFSIM_ICR_LEVEL7 | MCFSIM_ICR_PRI3)
 #define CFG_SYS_TIMER_PRESCALER      (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 #endif                          /* CONFIG_M5307 */
 
@@ -226,6 +244,8 @@
 #define CFG_SYS_TMRINTR_PEND           (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (6)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)
@@ -248,6 +268,8 @@
 #define CFG_SYS_TMRINTR_PEND   (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (6)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)
@@ -278,6 +300,8 @@
 #define CFG_SYS_TMRINTR_PEND           (CFG_SYS_TMRINTR_MASK)
 #define CFG_SYS_TMRINTR_PRI            (6)
 #define CFG_SYS_TIMER_PRESCALER        (((gd->bus_clk / 1000000) - 1) << 8)
+#else
+#define CFG_SYS_UDELAY_BASE            (MMAP_PIT0)
 #endif
 
 #define CFG_SYS_INTR_BASE              (MMAP_INTC0)

diff --git a/arch/m68k/lib/time.c b/arch/m68k/lib/time.c
index 500e4dbbba2baec47a7296a042a549b0ceec390b..61db1e6c5002deca349e3d258a707a67fe42d0e3 100644 (file)
--- a/arch/m68k/lib/time.c
+++ b/arch/m68k/lib/time.c
@@ -111,8 +111,6 @@ ulong get_timer(ulong base)
        return (timestamp - base);
 }
 
-#endif                         /* CONFIG_MCFTMR */
-
 /*
  * This function is derived from PowerPC code (read timebase as long long).
  * On M68K it just returns the timer value.
@@ -121,6 +119,40 @@ unsigned long long get_ticks(void)
 {
        return get_timer(0);
 }
+#else
+static u64 timer64 __section(".data");
+static u16 timer16 __section(".data");
+
+uint64_t __weak get_ticks(void)
+{
+       volatile pit_t *timerp = (pit_t *) (CFG_SYS_UDELAY_BASE);
+       u16 val = ~timerp->pcntr;
+
+       if (timer16 > val)
+               timer64 += 0xffff - timer16 + val;
+       else
+               timer64 += val - timer16;
+
+       timer16 = val;
+
+       return timer64;
+}
+
+/* PIT timer */
+int timer_init(void)
+{
+       volatile pit_t *timerp = (pit_t *) (CFG_SYS_UDELAY_BASE);
+
+       timer16 = 0;
+       timer64 = 0;
+
+       /* Set up PIT as timebase clock */
+       timerp->pmr = 0xffff;
+       timerp->pcsr = PIT_PCSR_EN | PIT_PCSR_OVW;
+
+       return 0;
+}
+#endif                         /* CONFIG_MCFTMR */
 
 unsigned long usec2ticks(unsigned long usec)
 {

diff --git a/common/board_f.c b/common/board_f.c
index f3c1ab53b1c681f919c865c38ce7665a5e6fd994..1688e27071fc19c1a0c20eef4a245a5415f2d9ab 100644 (file)
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -863,7 +863,7 @@ static const init_fnc_t init_sequence_f[] = {
        /* get CPU and bus clocks according to the environment variable */
        get_clocks,             /* get CPU and bus clocks (etc.) */
 #endif
-#if !defined(CONFIG_M68K)
+#if !defined(CONFIG_M68K) || (defined(CONFIG_M68K) && !defined(CONFIG_MCFTMR))
        timer_init,             /* initialize timer */
 #endif
 #if defined(CONFIG_BOARD_POSTCLK_INIT)