x86: Re-enable PCAT timer 2 for beeping
authorSimon Glass <sjg@chromium.org>
Wed, 17 Apr 2013 16:13:39 +0000 (16:13 +0000)
committerSimon Glass <sjg@chromium.org>
Mon, 13 May 2013 20:33:21 +0000 (13:33 -0700)
While we don't want PCAT timers for timing, we want timer 2 so that we can
still make a beep. Re-purpose the PCAT driver for this, and enable it in
coreboot.

Signed-off-by: Simon Glass <sjg@chromium.org>
arch/x86/include/asm/u-boot-x86.h
arch/x86/lib/Makefile
arch/x86/lib/pcat_timer.c
arch/x86/lib/tsc_timer.c
include/configs/coreboot.h

index bec583feb6a9ce41e50f7a952588a828a69536c2..22e093427fdf5c9426dbb002c668da27c3ca33a4 100644 (file)
@@ -41,6 +41,7 @@ typedef void (timer_fnc_t) (void);
 int register_timer_isr (timer_fnc_t *isr_func);
 unsigned long get_tbclk_mhz(void);
 void timer_set_base(uint64_t base);
+int pcat_timer_init(void);
 
 /* Architecture specific - can be in arch/x86/cpu/, arch/x86/lib/, or $(BOARD)/ */
 int dram_init_f(void);
index c61447978dcbd3d163e0012f79aa79ce9eaa5dc6..f66ad30741e597ec67e88b5f95ddd5ca2fb4e919 100644 (file)
@@ -31,7 +31,7 @@ COBJS-y       += gcc.o
 COBJS-y        += init_helpers.o
 COBJS-y        += interrupts.o
 COBJS-$(CONFIG_SYS_PCAT_INTERRUPTS) += pcat_interrupts.o
-COBJS-$(CONFIG_SYS_GENERIC_TIMER) += pcat_timer.o
+COBJS-$(CONFIG_SYS_PCAT_TIMER) += pcat_timer.o
 COBJS-$(CONFIG_PCI) += pci_type1.o
 COBJS-y        += relocate.o
 COBJS-y += physmem.o
index b0b6637f3a9ff119b150d1bdb1126d6df2f20f34..1ca3eb9e91875ae0f52db00fe1d44e918717ca0e 100644 (file)
 #include <common.h>
 #include <asm/io.h>
 #include <asm/i8254.h>
-#include <asm/ibmpc.h>
-#include <asm/interrupt.h>
 
-#define TIMER0_VALUE 0x04aa /* 1kHz 1.9318MHz / 1000 */
 #define TIMER2_VALUE 0x0a8e /* 440Hz */
 
-static int timer_init_done;
-
-int timer_init(void)
+int pcat_timer_init(void)
 {
-       /* initialize timer 0 and 2
-        *
-        * Timer 0 is used to increment system_tick 1000 times/sec
-        * Timer 1 was used for DRAM refresh in early PC's
-        * Timer 2 is used to drive the speaker
+       /*
+        * initialize 2, used to drive the speaker
         * (to start a beep: write 3 to port 0x61,
         * to stop it again: write 0)
         */
-       outb(PIT_CMD_CTR0 | PIT_CMD_BOTH | PIT_CMD_MODE2,
-                       PIT_BASE + PIT_COMMAND);
-       outb(TIMER0_VALUE & 0xff, PIT_BASE + PIT_T0);
-       outb(TIMER0_VALUE >> 8, PIT_BASE + PIT_T0);
-
        outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3,
                        PIT_BASE + PIT_COMMAND);
        outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2);
        outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2);
 
-       irq_install_handler(0, timer_isr, NULL);
-       unmask_irq(0);
-
-       timer_init_done = 1;
-
        return 0;
 }
-
-static u16 read_pit(void)
-{
-       u8 low;
-
-       outb(PIT_CMD_LATCH, PIT_BASE + PIT_COMMAND);
-       low = inb(PIT_BASE + PIT_T0);
-
-       return (inb(PIT_BASE + PIT_T0) << 8) | low;
-}
-
-/* this is not very exact */
-void __udelay(unsigned long usec)
-{
-       int counter;
-       int wraps;
-
-       if (timer_init_done) {
-               counter = read_pit();
-               wraps = usec / 1000;
-               usec = usec % 1000;
-
-               usec *= 1194;
-               usec /= 1000;
-               usec += counter;
-
-               while (usec > 1194) {
-                       usec -= 1194;
-                       wraps++;
-               }
-
-               while (1) {
-                       int new_count = read_pit();
-
-                       if (((new_count < usec) && !wraps) || wraps < 0)
-                               break;
-
-                       if (new_count > counter)
-                               wraps--;
-
-                       counter = new_count;
-               }
-       }
-
-}
index d931e5f5e0156a62455e36c3873d4a0e849616ed..c509801f9e8dee6539ac335e870748eb165aa62c 100644 (file)
@@ -98,6 +98,10 @@ void __udelay(unsigned long usec)
 
 int timer_init(void)
 {
-       /* Nothing to do here - the timer needs no init */
+#ifdef CONFIG_SYS_PCAT_TIMER
+       /* Set up the PCAT timer if required */
+       pcat_timer_init();
+#endif
+
        return 0;
 }
index 99408dcc582b906800ce95637d3533faaeb36080..7953ec6154daf09e80cacc344bb445e958d8a74f 100644 (file)
 
 #define CONFIG_SYS_X86_TSC_TIMER
 #define CONFIG_SYS_PCAT_INTERRUPTS
+#define CONFIG_SYS_PCAT_TIMER
 #define CONFIG_SYS_NUM_IRQS                    16
 
 /*-----------------------------------------------------------------------