x86, apbt: Moorestown APB system timer driver

Moorestown platform does not have PIT or HPET platform timers.  Instead it
has a bank of eight APB timers.  The number of available timers to the os
is exposed via SFI mtmr tables.  All APB timer interrupts are routed via
ioapic rtes and delivered as MSI.
Currently, we use timer 0 and 1 for per cpu clockevent devices, timer 2
for clocksource.

Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318D2D2@orsmsx508.amr.corp.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/arch/x86/include/asm/apb_timer.h b/arch/x86/include/asm/apb_timer.h
new file mode 100644
index 0000000..c74a2ee
--- /dev/null
+++ b/arch/x86/include/asm/apb_timer.h
@@ -0,0 +1,70 @@
+/*
+ * apb_timer.h: Driver for Langwell APB timer based on Synopsis DesignWare
+ *
+ * (C) Copyright 2009 Intel Corporation
+ * Author: Jacob Pan (jacob.jun.pan@intel.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ *
+ * Note:
+ */
+
+#ifndef ASM_X86_APBT_H
+#define ASM_X86_APBT_H
+#include <linux/sfi.h>
+
+#ifdef CONFIG_APB_TIMER
+
+/* Langwell DW APB timer registers */
+#define APBTMR_N_LOAD_COUNT    0x00
+#define APBTMR_N_CURRENT_VALUE 0x04
+#define APBTMR_N_CONTROL       0x08
+#define APBTMR_N_EOI           0x0c
+#define APBTMR_N_INT_STATUS    0x10
+
+#define APBTMRS_INT_STATUS     0xa0
+#define APBTMRS_EOI            0xa4
+#define APBTMRS_RAW_INT_STATUS 0xa8
+#define APBTMRS_COMP_VERSION   0xac
+#define APBTMRS_REG_SIZE       0x14
+
+/* register bits */
+#define APBTMR_CONTROL_ENABLE  (1<<0)
+#define APBTMR_CONTROL_MODE_PERIODIC   (1<<1) /*1: periodic 0:free running */
+#define APBTMR_CONTROL_INT     (1<<2)
+
+/* default memory mapped register base */
+#define LNW_SCU_ADDR           0xFF100000
+#define LNW_EXT_TIMER_OFFSET   0x1B800
+#define APBT_DEFAULT_BASE      (LNW_SCU_ADDR+LNW_EXT_TIMER_OFFSET)
+#define LNW_EXT_TIMER_PGOFFSET         0x800
+
+/* APBT clock speed range from PCLK to fabric base, 25-100MHz */
+#define APBT_MAX_FREQ          50
+#define APBT_MIN_FREQ          1
+#define APBT_MMAP_SIZE         1024
+
+#define APBT_DEV_USED  1
+
+extern void apbt_time_init(void);
+extern struct clock_event_device *global_clock_event;
+extern unsigned long apbt_quick_calibrate(void);
+extern int arch_setup_apbt_irqs(int irq, int trigger, int mask, int cpu);
+extern void apbt_setup_secondary_clock(void);
+extern unsigned int boot_cpu_id;
+extern int disable_apbt_percpu;
+
+extern struct sfi_timer_table_entry *sfi_get_mtmr(int hint);
+extern void sfi_free_mtmr(struct sfi_timer_table_entry *mtmr);
+extern int sfi_mtimer_num;
+
+#else /* CONFIG_APB_TIMER */
+
+static inline unsigned long apbt_quick_calibrate(void) {return 0; }
+static inline void apbt_time_init(void) {return 0; }
+
+#endif
+#endif /* ASM_X86_APBT_H */