Re: [Qemu-devel] [PATCH for 4.1 v3 6/6] riscv: Add a generic spike machine

[Alistair Francis <alistair23@gmail.com>]

On Thu, Apr 11, 2019 at 5:06 AM Igor Mammedov <imammedo@redhat.com> wrote:
>
> On Wed, 10 Apr 2019 23:11:00 +0000
> Alistair Francis <Alistair.Francis@wdc.com> wrote:
>
> > Add a generic spike machine (not tied to a version) and deprecate the
> > spike mahines that are tied to a specific version. As we can now specify
> > the CPU via the command line we no londer need specific versions of the
> > spike machines.
> >
> > Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
>
> For cpu and initial RAM related parts:
>
> Acked-by: Igor Mammedov <imammedo@redhat.com>
>
> a couple of questions below.
> > ---
> >  hw/riscv/spike.c | 106 ++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 105 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/riscv/spike.c b/hw/riscv/spike.c
> > index 2a000a5800..9d3f7cec4d 100644
> > --- a/hw/riscv/spike.c
> > +++ b/hw/riscv/spike.c
> > @@ -39,6 +39,7 @@
> >  #include "chardev/char.h"
> >  #include "sysemu/arch_init.h"
> >  #include "sysemu/device_tree.h"
> > +#include "sysemu/qtest.h"
> >  #include "exec/address-spaces.h"
> >  #include "elf.h"
> >
> > @@ -160,7 +161,89 @@ static void create_fdt(SpikeState *s, const struct MemmapEntry *memmap,
> >          qemu_fdt_add_subnode(fdt, "/chosen");
> >          qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", cmdline);
> >      }
> > - }
> > +}
> > +
> > +static void spike_board_init(MachineState *machine)
> > +{
> > +    const struct MemmapEntry *memmap = spike_memmap;
> > +
> > +    SpikeState *s = g_new0(SpikeState, 1);
> > +    MemoryRegion *system_memory = get_system_memory();
> > +    MemoryRegion *main_mem = g_new(MemoryRegion, 1);
> > +    MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
> > +    int i;
> > +
> > +    /* Initialize SOC */
> > +    object_initialize_child(OBJECT(machine), "soc", &s->soc, sizeof(s->soc),
> > +                            TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
> > +    object_property_set_str(OBJECT(&s->soc), machine->cpu_type, "cpu-type",
> > +                            &error_abort);
> > +    object_property_set_int(OBJECT(&s->soc), smp_cpus, "num-harts",
> > +                            &error_abort);
> > +    object_property_set_bool(OBJECT(&s->soc), true, "realized",
> > +                            &error_abort);
> > +
> > +    /* register system main memory (actual RAM) */
> > +    memory_region_init_ram(main_mem, NULL, "riscv.spike.ram",
> > +                           machine->ram_size, &error_fatal);
> do you really care about migration? if not then _nomigrate flavor would
> be more suitable.
>
> > +    memory_region_add_subregion(system_memory, memmap[SPIKE_DRAM].base,
> > +        main_mem);
> > +
> > +    /* create device tree */
> > +    create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
> > +
> > +    /* boot rom */
> > +    memory_region_init_rom(mask_rom, NULL, "riscv.spike.mrom",
> > +                           memmap[SPIKE_MROM].size, &error_fatal);
> > +    memory_region_add_subregion(system_memory, memmap[SPIKE_MROM].base,
> > +                                mask_rom);
> > +
> > +    if (machine->kernel_filename) {
> > +        load_kernel(machine->kernel_filename);
> > +    }
> > +
> > +    /* reset vector */
> > +    uint32_t reset_vec[8] = {
> > +        0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(dtb) */
> > +        0x02028593,                  /*     addi   a1, t0, %pcrel_lo(1b) */
> > +        0xf1402573,                  /*     csrr   a0, mhartid  */
> > +#if defined(TARGET_RISCV32)
> > +        0x0182a283,                  /*     lw     t0, 24(t0) */
> > +#elif defined(TARGET_RISCV64)
> > +        0x0182b283,                  /*     ld     t0, 24(t0) */
> > +#endif
> > +        0x00028067,                  /*     jr     t0 */
> > +        0x00000000,
> > +        memmap[SPIKE_DRAM].base,     /* start: .dword DRAM_BASE */
> > +        0x00000000,
> > +                                     /* dtb: */
> > +    };
> > +
> > +    /* copy in the reset vector in little_endian byte order */
> > +    for (i = 0; i < sizeof(reset_vec) >> 2; i++) {
> > +        reset_vec[i] = cpu_to_le32(reset_vec[i]);
> > +    }
> > +    rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
> > +                          memmap[SPIKE_MROM].base, &address_space_memory);
> > +
> > +    /* copy in the device tree */
> > +    if (fdt_pack(s->fdt) || fdt_totalsize(s->fdt) >
> > +            memmap[SPIKE_MROM].size - sizeof(reset_vec)) {
> > +        error_report("not enough space to store device-tree");
> > +        exit(1);
> > +    }
> > +    qemu_fdt_dumpdtb(s->fdt, fdt_totalsize(s->fdt));
> > +    rom_add_blob_fixed_as("mrom.fdt", s->fdt, fdt_totalsize(s->fdt),
> > +                          memmap[SPIKE_MROM].base + sizeof(reset_vec),
> > +                          &address_space_memory);
> > +
> > +    /* initialize HTIF using symbols found in load_kernel */
> > +    htif_mm_init(system_memory, mask_rom, &s->soc.harts[0].env, serial_hd(0));
> > +
> > +    /* Core Local Interruptor (timer and IPI) */
> > +    sifive_clint_create(memmap[SPIKE_CLINT].base, memmap[SPIKE_CLINT].size,
> > +        smp_cpus, SIFIVE_SIP_BASE, SIFIVE_TIMECMP_BASE, SIFIVE_TIME_BASE);
> > +}
> >
> >  static void spike_v1_10_0_board_init(MachineState *machine)
> >  {
> > @@ -172,6 +255,12 @@ static void spike_v1_10_0_board_init(MachineState *machine)
> >      MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
> >      int i;
> >
> > +    if (!qtest_enabled()) {
> > +        info_report("The Spike v1.10.0 machine has been depreceated. "
> > +                    "Please use the deneric spike machine and specify the ISA "
> > +                    "versions using -cpu.");
> > +    }
> Did you mean deprecated in sense that machines will be removed in 2 releases
> according to QEMU's deprecation policy?

That is the plan.

Alistair

>
> > +
> >      /* Initialize SOC */
> >      object_initialize_child(OBJECT(machine), "soc", &s->soc, sizeof(s->soc),
> >                              TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
> > @@ -254,6 +343,12 @@ static void spike_v1_09_1_board_init(MachineState *machine)
> >      MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
> >      int i;
> >
> > +    if (!qtest_enabled()) {
> > +        info_report("The Spike v1.09.1 machine has been depreceated. "
> > +                    "Please use the deneric spike machine and specify the ISA "
> > +                    "versions using -cpu.");
> > +    }
> > +
> >      /* Initialize SOC */
> >      object_initialize_child(OBJECT(machine), "soc", &s->soc, sizeof(s->soc),
> >                              TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
> > @@ -359,8 +454,17 @@ static void spike_v1_10_0_machine_init(MachineClass *mc)
> >      mc->desc = "RISC-V Spike Board (Privileged ISA v1.10)";
> >      mc->init = spike_v1_10_0_board_init;
> >      mc->max_cpus = 1;
> > +}
> > +
> > +static void spike_machine_init(MachineClass *mc)
> > +{
> > +    mc->desc = "RISC-V Spike Board";
> > +    mc->init = spike_board_init;
> > +    mc->max_cpus = 1;
> >      mc->is_default = 1;
> > +    mc->default_cpu_type = SPIKE_V1_10_0_CPU;
> >  }
> >
> >  DEFINE_MACHINE("spike_v1.9.1", spike_v1_09_1_machine_init)
> >  DEFINE_MACHINE("spike_v1.10", spike_v1_10_0_machine_init)
> > +DEFINE_MACHINE("spike", spike_machine_init)
>