include/hw/timer/cmsdk-apb-dualtimer.h

   1 /*
   2  * ARM CMSDK APB dual-timer emulation
   3  *
   4  * Copyright (c) 2018 Linaro Limited
   5  * Written by Peter Maydell
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 or
   9  *  (at your option) any later version.
  10  */
  11
  12 /*
  13  * This is a model of the "APB dual-input timer" which is part of the Cortex-M
  14  * System Design Kit (CMSDK) and documented in the Cortex-M System
  15  * Design Kit Technical Reference Manual (ARM DDI0479C):
  16  * https://developer.arm.com/products/system-design/system-design-kits/cortex-m-system-design-kit
  17  *
  18  * QEMU interface:
  19  *  + Clock input "TIMCLK": clock (for both timers)
  20  *  + sysbus MMIO region 0: the register bank
  21  *  + sysbus IRQ 0: combined timer interrupt TIMINTC
  22  *  + sysbus IRO 1: timer block 1 interrupt TIMINT1
  23  *  + sysbus IRQ 2: timer block 2 interrupt TIMINT2
  24  */
  25
  26 #ifndef CMSDK_APB_DUALTIMER_H
  27 #define CMSDK_APB_DUALTIMER_H
  28
  29 #include "hw/sysbus.h"
  30 #include "hw/ptimer.h"
  31 #include "hw/clock.h"
  32 #include "qom/object.h"
  33
  34 #define TYPE_CMSDK_APB_DUALTIMER "cmsdk-apb-dualtimer"
  35 OBJECT_DECLARE_SIMPLE_TYPE(CMSDKAPBDualTimer, CMSDK_APB_DUALTIMER)
  36
  37
  38 /* One of the two identical timer modules in the dual-timer module */
  39 typedef struct CMSDKAPBDualTimerModule {
  40     CMSDKAPBDualTimer *parent;
  41     struct ptimer_state *timer;
  42     qemu_irq timerint;
  43     /*
  44      * We must track the guest LOAD and VALUE register state by hand
  45      * rather than leaving this state only in the ptimer limit/count,
  46      * because if CONTROL.SIZE is 0 then only the low 16 bits of the
  47      * counter actually counts, but the high half is still guest
  48      * accessible.
  49      */
  50     uint32_t load;
  51     uint32_t value;
  52     uint32_t control;
  53     uint32_t intstatus;
  54 } CMSDKAPBDualTimerModule;
  55
  56 #define CMSDK_APB_DUALTIMER_NUM_MODULES 2
  57
  58 struct CMSDKAPBDualTimer {
  59     /*< private >*/
  60     SysBusDevice parent_obj;
  61
  62     /*< public >*/
  63     MemoryRegion iomem;
  64     qemu_irq timerintc;
  65     Clock *timclk;
  66
  67     CMSDKAPBDualTimerModule timermod[CMSDK_APB_DUALTIMER_NUM_MODULES];
  68     uint32_t timeritcr;
  69     uint32_t timeritop;
  70 };
  71
  72 #endif