diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2012-05-02 16:49:39 +0000 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2012-06-19 13:24:44 +0000 |
commit | 2a29ddee82029580fa85276767f73fedc30c8a0a (patch) | |
tree | 45ab75308ca2e331b61fe9758639c404f13bf3b3 /hw/armv7m_nvic.c | |
parent | b3387ede2f2b8a6ba3d5e922492f85a34db6f191 (diff) | |
download | hqemu-2a29ddee82029580fa85276767f73fedc30c8a0a.zip hqemu-2a29ddee82029580fa85276767f73fedc30c8a0a.tar.gz |
hw/armv7m_nvic: Use MemoryRegions for NVIC specific registers
Implement the NVIC specific register areas using a set of
overlaid MemoryRegions in a container, rather than by having
the arm_gic read/write functions use special purpose callbacks.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/armv7m_nvic.c')
-rw-r--r-- | hw/armv7m_nvic.c | 74 |
1 files changed, 73 insertions, 1 deletions
diff --git a/hw/armv7m_nvic.c b/hw/armv7m_nvic.c index 653c011..747e245 100644 --- a/hw/armv7m_nvic.c +++ b/hw/armv7m_nvic.c @@ -30,9 +30,16 @@ typedef struct { int64_t tick; QEMUTimer *timer; } systick; + MemoryRegion sysregmem; + MemoryRegion gic_iomem_alias; + MemoryRegion container; uint32_t num_irq; } nvic_state; +static const uint8_t nvic_id[] = { + 0x00, 0xb0, 0x1b, 0x00, 0x0d, 0xe0, 0x05, 0xb1 +}; + /* qemu timers run at 1GHz. We want something closer to 1MHz. */ #define SYSTICK_SCALE 1000ULL @@ -358,12 +365,54 @@ static void nvic_writel(void *opaque, uint32_t offset, uint32_t value) case 0xd38: /* Bus Fault Address. */ case 0xd3c: /* Aux Fault Status. */ goto bad_reg; + case 0xf00: /* Software Triggered Interrupt Register */ + if ((value & 0x1ff) < s->num_irq) { + gic_set_pending_private(&s->gic, 0, value & 0x1ff); + } + break; default: bad_reg: hw_error("NVIC: Bad write offset 0x%x\n", offset); } } +static uint64_t nvic_sysreg_read(void *opaque, target_phys_addr_t addr, + unsigned size) +{ + /* At the moment we only support the ID registers for byte/word access. + * This is not strictly correct as a few of the other registers also + * allow byte access. + */ + uint32_t offset = addr; + if (offset >= 0xfe0) { + if (offset & 3) { + return 0; + } + return nvic_id[(offset - 0xfe0) >> 2]; + } + if (size == 4) { + return nvic_readl(opaque, offset); + } + hw_error("NVIC: Bad read of size %d at offset 0x%x\n", size, offset); +} + +static void nvic_sysreg_write(void *opaque, target_phys_addr_t addr, + uint64_t value, unsigned size) +{ + uint32_t offset = addr; + if (size == 4) { + nvic_writel(opaque, offset, value); + return; + } + hw_error("NVIC: Bad write of size %d at offset 0x%x\n", size, offset); +} + +static const MemoryRegionOps nvic_sysreg_ops = { + .read = nvic_sysreg_read, + .write = nvic_sysreg_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + static const VMStateDescription vmstate_nvic = { .name = "armv7m_nvic", .version_id = 1, @@ -399,7 +448,30 @@ static int armv7m_nvic_init(SysBusDevice *dev) /* The NVIC always has only one CPU */ s->gic.num_cpu = 1; gic_init(&s->gic, s->num_irq); - memory_region_add_subregion(get_system_memory(), 0xe000e000, &s->gic.iomem); + /* The NVIC and system controller register area looks like this: + * 0..0xff : system control registers, including systick + * 0x100..0xcff : GIC-like registers + * 0xd00..0xfff : system control registers + * We use overlaying to put the GIC like registers + * over the top of the system control register region. + */ + memory_region_init(&s->container, "nvic", 0x1000); + /* The system register region goes at the bottom of the priority + * stack as it covers the whole page. + */ + memory_region_init_io(&s->sysregmem, &nvic_sysreg_ops, s, + "nvic_sysregs", 0x1000); + memory_region_add_subregion(&s->container, 0, &s->sysregmem); + /* Alias the GIC region so we can get only the section of it + * we need, and layer it on top of the system register region. + */ + memory_region_init_alias(&s->gic_iomem_alias, "nvic-gic", &s->gic.iomem, + 0x100, 0xc00); + memory_region_add_subregion_overlap(&s->container, 0x100, &s->gic.iomem, 1); + /* Map the whole thing into system memory at the location required + * by the v7M architecture. + */ + memory_region_add_subregion(get_system_memory(), 0xe000e000, &s->container); s->systick.timer = qemu_new_timer_ns(vm_clock, systick_timer_tick, s); return 0; } |