Re: [PATCH 3/4] hw/riscv: Allow creating multiple instances of PLIC

[Alistair Francis]

On Fri, May 15, 2020 at 11:39 PM Anup Patel <address@hidden> wrote:
>
> We extend PLIC emulation to allow multiple instances of PLIC in
> a QEMU RISC-V machine. To achieve this, we remove first HART id
> zero assumption from PLIC emulation.
>
> Signed-off-by: Anup Patel <address@hidden>

Reviewed-by: Alistair Francis <address@hidden>

Alistair

> ---
>  hw/riscv/sifive_e.c            |  2 +-
>  hw/riscv/sifive_plic.c         | 24 +++++++++++++-----------
>  hw/riscv/sifive_u.c            |  2 +-
>  hw/riscv/virt.c                |  2 +-
>  include/hw/riscv/sifive_plic.h | 12 +++++++-----
>  5 files changed, 23 insertions(+), 19 deletions(-)
>
> diff --git a/hw/riscv/sifive_e.c b/hw/riscv/sifive_e.c
> index 1c3b37d0ba..bd122e71ae 100644
> --- a/hw/riscv/sifive_e.c
> +++ b/hw/riscv/sifive_e.c
> @@ -152,7 +152,7 @@ static void riscv_sifive_e_soc_realize(DeviceState *dev, 
> Error **errp)
>
>      /* MMIO */
>      s->plic = sifive_plic_create(memmap[SIFIVE_E_PLIC].base,
> -        (char *)SIFIVE_E_PLIC_HART_CONFIG,
> +        (char *)SIFIVE_E_PLIC_HART_CONFIG, 0,
>          SIFIVE_E_PLIC_NUM_SOURCES,
>          SIFIVE_E_PLIC_NUM_PRIORITIES,
>          SIFIVE_E_PLIC_PRIORITY_BASE,
> diff --git a/hw/riscv/sifive_plic.c b/hw/riscv/sifive_plic.c
> index c1e04cbb98..f88bb48053 100644
> --- a/hw/riscv/sifive_plic.c
> +++ b/hw/riscv/sifive_plic.c
> @@ -352,6 +352,7 @@ static const MemoryRegionOps sifive_plic_ops = {
>
>  static Property sifive_plic_properties[] = {
>      DEFINE_PROP_STRING("hart-config", SiFivePLICState, hart_config),
> +    DEFINE_PROP_UINT32("hartid-base", SiFivePLICState, hartid_base, 0),
>      DEFINE_PROP_UINT32("num-sources", SiFivePLICState, num_sources, 0),
>      DEFINE_PROP_UINT32("num-priorities", SiFivePLICState, num_priorities, 0),
>      DEFINE_PROP_UINT32("priority-base", SiFivePLICState, priority_base, 0),
> @@ -400,10 +401,12 @@ static void parse_hart_config(SiFivePLICState *plic)
>      }
>      hartid++;
>
> -    /* store hart/mode combinations */
>      plic->num_addrs = addrid;
> +    plic->num_harts = hartid;
> +
> +    /* store hart/mode combinations */
>      plic->addr_config = g_new(PLICAddr, plic->num_addrs);
> -    addrid = 0, hartid = 0;
> +    addrid = 0, hartid = plic->hartid_base;
>      p = plic->hart_config;
>      while ((c = *p++)) {
>          if (c == ',') {
> @@ -429,8 +432,6 @@ static void sifive_plic_irq_request(void *opaque, int 
> irq, int level)
>
>  static void sifive_plic_realize(DeviceState *dev, Error **errp)
>  {
> -    MachineState *ms = MACHINE(qdev_get_machine());
> -    unsigned int smp_cpus = ms->smp.cpus;
>      SiFivePLICState *plic = SIFIVE_PLIC(dev);
>      int i;
>
> @@ -451,8 +452,8 @@ static void sifive_plic_realize(DeviceState *dev, Error 
> **errp)
>       * lost a interrupt in the case a PLIC is attached. The SEIP bit must be
>       * hardware controlled when a PLIC is attached.
>       */
> -    for (i = 0; i < smp_cpus; i++) {
> -        RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(i));
> +    for (i = 0; i < plic->num_harts; i++) {
> +        RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(plic->hartid_base + i));
>          if (riscv_cpu_claim_interrupts(cpu, MIP_SEIP) < 0) {
>              error_report("SEIP already claimed");
>              exit(1);
> @@ -488,16 +489,17 @@ type_init(sifive_plic_register_types)
>   * Create PLIC device.
>   */
>  DeviceState *sifive_plic_create(hwaddr addr, char *hart_config,
> -    uint32_t num_sources, uint32_t num_priorities,
> -    uint32_t priority_base, uint32_t pending_base,
> -    uint32_t enable_base, uint32_t enable_stride,
> -    uint32_t context_base, uint32_t context_stride,
> -    uint32_t aperture_size)
> +    uint32_t hartid_base, uint32_t num_sources,
> +    uint32_t num_priorities, uint32_t priority_base,
> +    uint32_t pending_base, uint32_t enable_base,
> +    uint32_t enable_stride, uint32_t context_base,
> +    uint32_t context_stride, uint32_t aperture_size)
>  {
>      DeviceState *dev = qdev_create(NULL, TYPE_SIFIVE_PLIC);
>      assert(enable_stride == (enable_stride & -enable_stride));
>      assert(context_stride == (context_stride & -context_stride));
>      qdev_prop_set_string(dev, "hart-config", hart_config);
> +    qdev_prop_set_uint32(dev, "hartid-base", hartid_base);
>      qdev_prop_set_uint32(dev, "num-sources", num_sources);
>      qdev_prop_set_uint32(dev, "num-priorities", num_priorities);
>      qdev_prop_set_uint32(dev, "priority-base", priority_base);
> diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
> index 22997fbf13..69dbd7980b 100644
> --- a/hw/riscv/sifive_u.c
> +++ b/hw/riscv/sifive_u.c
> @@ -585,7 +585,7 @@ static void riscv_sifive_u_soc_realize(DeviceState *dev, 
> Error **errp)
>
>      /* MMIO */
>      s->plic = sifive_plic_create(memmap[SIFIVE_U_PLIC].base,
> -        plic_hart_config,
> +        plic_hart_config, 0,
>          SIFIVE_U_PLIC_NUM_SOURCES,
>          SIFIVE_U_PLIC_NUM_PRIORITIES,
>          SIFIVE_U_PLIC_PRIORITY_BASE,
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index dcb8a83b35..f40efcb193 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -585,7 +585,7 @@ static void riscv_virt_board_init(MachineState *machine)
>
>      /* MMIO */
>      s->plic = sifive_plic_create(memmap[VIRT_PLIC].base,
> -        plic_hart_config,
> +        plic_hart_config, 0,
>          VIRT_PLIC_NUM_SOURCES,
>          VIRT_PLIC_NUM_PRIORITIES,
>          VIRT_PLIC_PRIORITY_BASE,
> diff --git a/include/hw/riscv/sifive_plic.h b/include/hw/riscv/sifive_plic.h
> index 4421e81249..ace76d0f1b 100644
> --- a/include/hw/riscv/sifive_plic.h
> +++ b/include/hw/riscv/sifive_plic.h
> @@ -48,6 +48,7 @@ typedef struct SiFivePLICState {
>      /*< public >*/
>      MemoryRegion mmio;
>      uint32_t num_addrs;
> +    uint32_t num_harts;
>      uint32_t bitfield_words;
>      PLICAddr *addr_config;
>      uint32_t *source_priority;
> @@ -58,6 +59,7 @@ typedef struct SiFivePLICState {
>
>      /* config */
>      char *hart_config;
> +    uint32_t hartid_base;
>      uint32_t num_sources;
>      uint32_t num_priorities;
>      uint32_t priority_base;
> @@ -70,10 +72,10 @@ typedef struct SiFivePLICState {
>  } SiFivePLICState;
>
>  DeviceState *sifive_plic_create(hwaddr addr, char *hart_config,
> -    uint32_t num_sources, uint32_t num_priorities,
> -    uint32_t priority_base, uint32_t pending_base,
> -    uint32_t enable_base, uint32_t enable_stride,
> -    uint32_t context_base, uint32_t context_stride,
> -    uint32_t aperture_size);
> +    uint32_t hartid_base, uint32_t num_sources,
> +    uint32_t num_priorities, uint32_t priority_base,
> +    uint32_t pending_base, uint32_t enable_base,
> +    uint32_t enable_stride, uint32_t context_base,
> +    uint32_t context_stride, uint32_t aperture_size);
>
>  #endif
> --
> 2.25.1
>
>