diff options
author | Clément Chigot <chigot@adacore.com> | 2024-01-31 09:50:41 +0100 |
---|---|---|
committer | Philippe Mathieu-Daudé <philmd@linaro.org> | 2024-02-15 16:58:46 +0100 |
commit | 7ed9a5f626a6c932a8c869a91e6a8b3e2029f5ef (patch) | |
tree | b15ea960943c90ae487fbe9d0c17d5bca0d57a08 /hw | |
parent | 6bf147854395f39fe45abebe40529bf7f023aeb9 (diff) | |
download | qemu-7ed9a5f626a6c932a8c869a91e6a8b3e2029f5ef.zip qemu-7ed9a5f626a6c932a8c869a91e6a8b3e2029f5ef.tar.gz qemu-7ed9a5f626a6c932a8c869a91e6a8b3e2029f5ef.tar.bz2 |
hw/intc/grlib_irqmp: implements the multiprocessor status register
This implements the multiprocessor status register in grlib-irqmp and
bind it to a start signal, which will be later wired in leon3-generic
to start a cpu.
The EIRQ and BA bits are not implemented.
Based on https://gaisler.com/doc/gr712rc-usermanual.pdf, §8.3.5.
Co-developed-by: Frederic Konrad <konrad.frederic@yahoo.fr>
Signed-off-by: Clément Chigot <chigot@adacore.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240131085047.18458-4-chigot@adacore.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Diffstat (limited to 'hw')
-rw-r--r-- | hw/intc/grlib_irqmp.c | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/hw/intc/grlib_irqmp.c b/hw/intc/grlib_irqmp.c index 744cd64..1e073bd 100644 --- a/hw/intc/grlib_irqmp.c +++ b/hw/intc/grlib_irqmp.c @@ -52,6 +52,10 @@ #define FORCE_OFFSET 0x80 #define EXTENDED_OFFSET 0xC0 +/* Multiprocessor Status Register */ +#define MP_STATUS_CPU_STATUS_MASK ((1 << IRQMP_MAX_CPU)-2) +#define MP_STATUS_NCPU_SHIFT 28 + #define MAX_PILS 16 OBJECT_DECLARE_SIMPLE_TYPE(IRQMP, GRLIB_IRQMP) @@ -65,6 +69,7 @@ struct IRQMP { unsigned int ncpus; IRQMPState *state; + qemu_irq start_signal[IRQMP_MAX_CPU]; qemu_irq irq; }; @@ -72,6 +77,7 @@ struct IRQMPState { uint32_t level; uint32_t pending; uint32_t clear; + uint32_t mpstatus; uint32_t broadcast; uint32_t mask[IRQMP_MAX_CPU]; @@ -182,10 +188,12 @@ static uint64_t grlib_irqmp_read(void *opaque, hwaddr addr, return state->force[0]; case CLEAR_OFFSET: - case MP_STATUS_OFFSET: /* Always read as 0 */ return 0; + case MP_STATUS_OFFSET: + return state->mpstatus; + case BROADCAST_OFFSET: return state->broadcast; @@ -224,8 +232,9 @@ static uint64_t grlib_irqmp_read(void *opaque, hwaddr addr, static void grlib_irqmp_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { - IRQMP *irqmp = opaque; + IRQMP *irqmp = opaque; IRQMPState *state; + int i; assert(irqmp != NULL); state = irqmp->state; @@ -258,7 +267,18 @@ static void grlib_irqmp_write(void *opaque, hwaddr addr, return; case MP_STATUS_OFFSET: - /* Read Only (no SMP support) */ + /* + * Writing and reading operations are reversed for the CPU status. + * Writing "1" will start the CPU, but reading "1" means that the CPU + * is power-down. + */ + value &= MP_STATUS_CPU_STATUS_MASK; + for (i = 0; i < irqmp->ncpus; i++) { + if ((value >> i) & 1) { + qemu_set_irq(irqmp->start_signal[i], 1); + state->mpstatus &= ~(1 << i); + } + } return; case BROADCAST_OFFSET: @@ -325,6 +345,8 @@ static void grlib_irqmp_reset(DeviceState *d) memset(irqmp->state, 0, sizeof *irqmp->state); irqmp->state->parent = irqmp; + irqmp->state->mpstatus = ((irqmp->ncpus - 1) << MP_STATUS_NCPU_SHIFT) | + ((1 << irqmp->ncpus) - 2); } static void grlib_irqmp_realize(DeviceState *dev, Error **errp) @@ -338,6 +360,13 @@ static void grlib_irqmp_realize(DeviceState *dev, Error **errp) } qdev_init_gpio_in(dev, grlib_irqmp_set_irq, MAX_PILS); + + /* + * Transitionning from 0 to 1 starts the CPUs. The opposite can't + * happen. + */ + qdev_init_gpio_out_named(dev, irqmp->start_signal, "grlib-start-cpu", + IRQMP_MAX_CPU); qdev_init_gpio_out_named(dev, &irqmp->irq, "grlib-irq", 1); memory_region_init_io(&irqmp->iomem, OBJECT(dev), &grlib_irqmp_ops, irqmp, "irqmp", IRQMP_REG_SIZE); |