On Wed, Jun 3, 2026 at 5:04 PM Joel Stanley <[email protected]> wrote:
>
> The Tenstorrent Atlantis platform is a collaboration between Tenstorrent
> and CoreLab Technology. It is based on the Atlantis SoC, which includes
> the Ascalon-X CPU and other IP from Tenstorrent and CoreLab Technology.
> The Tenstorrent Ascalon-X is a high performance 64-bit RVA23 compliant
> RISC-V CPU.
>
> Add the tt-atlantis machine containing serial console, interrupt
> controllers, and device tree support.
>
> The Atlantis boot images loaded from include OpenSBI and an initial DTB
> that is passed to OpenSBI. This is approximated in the model by having
> QEMU build the device tree rather than load a DTB image directly.
> Subsequent stages may use the modified DTB provided by OpenSBI or opt to
> supply their own.
>
> qemu-system-riscv64 -M tt-atlantis -m 512M \
> -kernel Image -initrd rootfs.cpio -nographic
>
> Co-Developed-by: Nicholas Piggin <[email protected]>
> Signed-off-by: Nicholas Piggin <[email protected]>
> Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
> Reviewed-by: Chao Liu <[email protected]>
> Signed-off-by: Joel Stanley <[email protected]>
> ---
> MAINTAINERS | 10 +
> docs/system/riscv/tt_atlantis.rst | 41 +++
> docs/system/target-riscv.rst | 1 +
> include/hw/riscv/tt_atlantis.h | 50 +++
> hw/riscv/tt_atlantis.c | 593 ++++++++++++++++++++++++++++++
> hw/riscv/Kconfig | 10 +
> hw/riscv/meson.build | 1 +
> 7 files changed, 706 insertions(+)
> create mode 100644 docs/system/riscv/tt_atlantis.rst
> create mode 100644 include/hw/riscv/tt_atlantis.h
> create mode 100644 hw/riscv/tt_atlantis.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7752917d8cfb..e52aa769c9ae 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1784,6 +1784,16 @@ F: hw/*/*sifive*.c
> F: include/hw/*/*sifive*.h
> F: tests/functional/test_riscv64_sifive_u.py
>
> +Tenstorrent Machines
> +M: Joel Stanley <[email protected]>
> +R: Nicholas Piggin <[email protected]>
> +R: Michael Ellerman <[email protected]>
> +L: [email protected]
> +S: Supported
> +F: docs/system/riscv/tt_*.rst
> +F: hw/riscv/tt_*.c
> +F: include/hw/riscv/tt_*.h
> +
> AMD Microblaze-V Generic Board
> M: Sai Pavan Boddu <[email protected]>
> S: Maintained
> diff --git a/docs/system/riscv/tt_atlantis.rst
> b/docs/system/riscv/tt_atlantis.rst
> new file mode 100644
> index 000000000000..1f2880d61773
> --- /dev/null
> +++ b/docs/system/riscv/tt_atlantis.rst
> @@ -0,0 +1,41 @@
> +Tenstorrent Atlantis (``tt-atlantis``)
> +======================================
> +
> +The Tenstorrent Atlantis platform is a collaboration between Tenstorrent
> +and CoreLab Technology. It is based on the Atlantis SoC, which includes
> +the Ascalon-X CPU and other IP from Tenstorrent and CoreLab Technology.
> +
> +The Tenstorrent Ascalon-X is a high performance 64-bit RVA23 compliant
> +RISC-V CPU.
> +
> +tt-atlantis QEMU model features
> +-------------------------------
> +
> +* 8-core Ascalon-X CPU Cluster
> +* RISC-V compliant Advanced Interrupt Architecture
> +* 16550A compatible UART
> +
> +Known limitations
> +-----------------
> +
> +The QEMU tt-atlantis machine does not yet model every device on the
> +real platform. Notably:
> +
> +* There is no PCI host bridge, so virtio-pci devices cannot be
> + attached. Boots that need block storage must use ``-initrd`` with
> + an initramfs.
> +* The DesignWare UART is modelled with QEMU's ns16550-compatible
> + ``serial_mm`` device; DesignWare-specific registers beyond that
> + set return 0.
> +
> +Supported software
> +------------------
> +
> +The Tenstorrent Ascalon CPUs avoid proprietary or non-standard
> +extensions, so compatibility with existing software is generally
> +good. The QEMU tt-atlantis machine works with upstream OpenSBI
> +and Linux with default configurations.
> +
> +The development board hardware will require some implementation
> +specific setup in firmware which is being developed and may
> +become a requirement or option for the tt-atlantis machine.
> diff --git a/docs/system/target-riscv.rst b/docs/system/target-riscv.rst
> index 3ad5d1ddafbb..a8e6b3342186 100644
> --- a/docs/system/target-riscv.rst
> +++ b/docs/system/target-riscv.rst
> @@ -71,6 +71,7 @@ undocumented; you can get a complete list by running
> riscv/mips
> riscv/shakti-c
> riscv/sifive_u
> + riscv/tt_atlantis
> riscv/virt
> riscv/xiangshan-kunminghu
>
> diff --git a/include/hw/riscv/tt_atlantis.h b/include/hw/riscv/tt_atlantis.h
> new file mode 100644
> index 000000000000..a17732ce8114
> --- /dev/null
> +++ b/include/hw/riscv/tt_atlantis.h
> @@ -0,0 +1,50 @@
> +/*
> + * Tenstorrent Atlantis RISC-V System on Chip
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * Copyright 2025 Tenstorrent, Joel Stanley <[email protected]>
> + */
> +
> +#ifndef HW_RISCV_TT_ATLANTIS_H
> +#define HW_RISCV_TT_ATLANTIS_H
> +
> +#include "hw/core/boards.h"
> +#include "hw/core/sysbus.h"
> +#include "hw/intc/riscv_imsic.h"
> +#include "hw/riscv/riscv_hart.h"
> +
> +#define TYPE_TT_ATLANTIS_MACHINE MACHINE_TYPE_NAME("tt-atlantis")
> +OBJECT_DECLARE_SIMPLE_TYPE(TTAtlantisState, TT_ATLANTIS_MACHINE)
> +
> +struct TTAtlantisState {
> + /*< private >*/
> + MachineState parent;
> +
> + /*< public >*/
> + Notifier machine_done;
> + const MemMapEntry *memmap;
> +
> + RISCVHartArrayState soc;
> + DeviceState *irqchip;
> +
> + int fdt_size;
> +};
> +
> +enum {
> + TT_ATL_UART1_IRQ = 39,
> +};
> +
> +enum {
> + TT_ATL_ACLINT,
> + TT_ATL_BOOTROM,
> + TT_ATL_DDR_LO,
> + TT_ATL_DDR_HI,
> + TT_ATL_MAPLIC,
> + TT_ATL_MIMSIC,
> + TT_ATL_SAPLIC,
> + TT_ATL_SIMSIC,
> + TT_ATL_UART1,
> +};
> +
> +#endif
> diff --git a/hw/riscv/tt_atlantis.c b/hw/riscv/tt_atlantis.c
> new file mode 100644
> index 000000000000..1ccd7d017c56
> --- /dev/null
> +++ b/hw/riscv/tt_atlantis.c
> @@ -0,0 +1,593 @@
> +/*
> + * Tenstorrent Atlantis RISC-V System on Chip
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * Copyright 2025 Tenstorrent, Joel Stanley <[email protected]>
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/cutils.h"
> +#include "qemu/error-report.h"
> +#include "qemu/guest-random.h"
> +#include "qemu/units.h"
> +
> +#include "hw/core/boards.h"
> +#include "hw/core/loader.h"
> +#include "hw/core/sysbus.h"
> +
> +#include "target/riscv/cpu.h"
> +#include "target/riscv/pmu.h"
> +
> +#include "hw/riscv/boot.h"
> +#include "hw/riscv/machines-qom.h"
> +#include "hw/riscv/riscv_hart.h"
> +
> +#include "hw/char/serial-mm.h"
> +#include "hw/intc/riscv_aclint.h"
> +#include "hw/misc/unimp.h"
> +
> +#include "system/system.h"
> +#include "system/device_tree.h"
> +
> +#include "hw/riscv/tt_atlantis.h"
> +
> +#include "aia.h"
> +
> +#define TT_IRQCHIP_NUM_MSIS 255
> +#define TT_IRQCHIP_NUM_SOURCES 128
> +#define TT_IRQCHIP_NUM_PRIO_BITS 3
> +#define TT_IRQCHIP_GUESTS 63 /* aia_guests, gives guest_index_bits=6
> */
> +#define TT_IRQCHIP_MIMSIC_STRIDE 0x40000
> +
> +#define TT_ACLINT_MTIME_SIZE 0x8050
> +#define TT_ACLINT_MTIME 0x0
> +#define TT_ACLINT_MTIMECMP 0x8000
> +#define TT_ACLINT_TIMEBASE_FREQ 1000000000
> +
> +static const MemMapEntry tt_atlantis_memmap[] = {
> + /* Keep sorted with :'<,'>!sort -g -k 4 */
> + [TT_ATL_DDR_LO] = { 0x00000000, 0x80000000 },
> + [TT_ATL_BOOTROM] = { 0x80000000, 0x2000 },
> + [TT_ATL_MIMSIC] = { 0xa0000000, 0x200000 },
> + [TT_ATL_ACLINT] = { 0xa2180000, 0x10000 },
> + [TT_ATL_SIMSIC] = { 0xa4000000, 0x200000 },
> + [TT_ATL_MAPLIC] = { 0xcc000000, 0x4000000 },
> + [TT_ATL_UART1] = { 0xd4110000, 0x10000 },
> + [TT_ATL_SAPLIC] = { 0xe8000000, 0x4000000 },
> + [TT_ATL_DDR_HI] = { 0x100000000, 0x1000000000 },
> +};
> +
> +static uint32_t next_phandle(void)
> +{
> + static uint32_t phandle = 1;
> + return phandle++;
> +}
> +
> +static void create_fdt_cpus(TTAtlantisState *s, uint32_t *intc_phandles)
> +{
> + uint32_t cpu_phandle;
> + void *fdt = MACHINE(s)->fdt;
> +
> + for (int cpu = s->soc.num_harts - 1; cpu >= 0; cpu--) {
> + RISCVCPU *cpu_ptr = &s->soc.harts[cpu];
> + g_autofree char *cpu_name = NULL;
> + g_autofree char *intc_name = NULL;
> +
> + cpu_phandle = next_phandle();
> +
> + cpu_name = g_strdup_printf("/cpus/cpu@%d", s->soc.hartid_base + cpu);
> + qemu_fdt_add_subnode(fdt, cpu_name);
> +
> + qemu_fdt_setprop_string(fdt, cpu_name, "mmu-type", "riscv,sv57");
> +
> + riscv_isa_write_fdt(cpu_ptr, fdt, cpu_name);
> +
> + qemu_fdt_setprop_cell(fdt, cpu_name, "riscv,cbom-block-size",
> + cpu_ptr->cfg.cbom_blocksize);
> +
> + qemu_fdt_setprop_cell(fdt, cpu_name, "riscv,cboz-block-size",
> + cpu_ptr->cfg.cboz_blocksize);
> +
> + qemu_fdt_setprop_cell(fdt, cpu_name, "riscv,cbop-block-size",
> + cpu_ptr->cfg.cbop_blocksize);
> +
> + qemu_fdt_setprop_string(fdt, cpu_name, "compatible", "riscv");
> + qemu_fdt_setprop_string(fdt, cpu_name, "status", "okay");
> + qemu_fdt_setprop_cell(fdt, cpu_name, "reg", s->soc.hartid_base +
> cpu);
> + qemu_fdt_setprop_string(fdt, cpu_name, "device_type", "cpu");
> + qemu_fdt_setprop_cell(fdt, cpu_name, "phandle", cpu_phandle);
> +
> + intc_phandles[cpu] = next_phandle();
> +
> + intc_name = g_strdup_printf("%s/interrupt-controller", cpu_name);
> + qemu_fdt_add_subnode(fdt, intc_name);
> + qemu_fdt_setprop_cell(fdt, intc_name, "phandle",
> + intc_phandles[cpu]);
> + qemu_fdt_setprop_string(fdt, intc_name, "compatible",
> + "riscv,cpu-intc");
> + qemu_fdt_setprop(fdt, intc_name, "interrupt-controller", NULL, 0);
> + qemu_fdt_setprop_cell(fdt, intc_name, "#interrupt-cells", 1);
> + }
> +}
> +
> +static void create_fdt_memory_node(TTAtlantisState *s,
> + hwaddr addr, hwaddr size)
> +{
> + void *fdt = MACHINE(s)->fdt;
> + g_autofree char *name = g_strdup_printf("/memory@%"HWADDR_PRIX, addr);
> + qemu_fdt_add_subnode(fdt, name);
> + qemu_fdt_setprop_sized_cells(fdt, name, "reg", 2, addr, 2, size);
> + qemu_fdt_setprop_string(fdt, name, "device_type", "memory");
> +}
> +
> +static void create_fdt_memory(TTAtlantisState *s)
> +{
> + hwaddr size_lo = MACHINE(s)->ram_size;
> + hwaddr size_hi = 0;
> +
> + if (size_lo > s->memmap[TT_ATL_DDR_LO].size) {
> + size_lo = s->memmap[TT_ATL_DDR_LO].size;
> + size_hi = MACHINE(s)->ram_size - size_lo;
> + }
> +
> + create_fdt_memory_node(s, s->memmap[TT_ATL_DDR_LO].base, size_lo);
> + if (size_hi) {
> + /*
> + * The first part of the HI address is aliased at the LO address
> + * so do not include that as usable memory. Is there any way
> + * (or good reason) to describe that aliasing 2GB with DT?
> + */
> + create_fdt_memory_node(s, s->memmap[TT_ATL_DDR_HI].base + size_lo,
> + size_hi);
> + }
> +}
> +
> +static void create_fdt_aclint(TTAtlantisState *s, uint32_t *intc_phandles)
> +{
> + void *fdt = MACHINE(s)->fdt;
> + g_autofree char *name = NULL;
> + g_autofree uint32_t *aclint_mtimer_cells = NULL;
> + uint32_t aclint_cells_size;
> + hwaddr addr;
> +
> + aclint_mtimer_cells = g_new0(uint32_t, s->soc.num_harts * 2);
> +
> + for (int cpu = 0; cpu < s->soc.num_harts; cpu++) {
> + aclint_mtimer_cells[cpu * 2 + 0] = cpu_to_be32(intc_phandles[cpu]);
> + aclint_mtimer_cells[cpu * 2 + 1] = cpu_to_be32(IRQ_M_TIMER);
> + }
> + aclint_cells_size = s->soc.num_harts * sizeof(uint32_t) * 2;
> +
> + addr = s->memmap[TT_ATL_ACLINT].base;
> +
> + name = g_strdup_printf("/soc/mtimer@%"HWADDR_PRIX, addr);
> + qemu_fdt_add_subnode(fdt, name);
> + qemu_fdt_setprop_string(fdt, name, "compatible", "riscv,aclint-mtimer");
> + qemu_fdt_setprop_sized_cells(fdt, name, "reg",
> + 2, addr + TT_ACLINT_MTIME,
> + 2, 0x1000,
> + 2, addr + TT_ACLINT_MTIMECMP,
> + 2, 0x1000);
> + qemu_fdt_setprop(fdt, name, "interrupts-extended",
> + aclint_mtimer_cells, aclint_cells_size);
> +}
> +
> +static void create_fdt_one_imsic(void *fdt, const MemMapEntry *mem, int cpus,
> + uint32_t *intc_phandles, uint32_t
> msi_phandle,
> + int irq_line, uint32_t imsic_guest_bits)
> +{
> + g_autofree char *name = NULL;
> + g_autofree uint32_t *imsic_cells = g_new0(uint32_t, cpus * 2);
> +
> + for (int cpu = 0; cpu < cpus; cpu++) {
> + imsic_cells[cpu * 2 + 0] = cpu_to_be32(intc_phandles[cpu]);
> + imsic_cells[cpu * 2 + 1] = cpu_to_be32(irq_line);
> + }
> +
> + name = g_strdup_printf("/soc/interrupt-controller@%"HWADDR_PRIX,
> mem->base);
> + qemu_fdt_add_subnode(fdt, name);
> + qemu_fdt_setprop_string(fdt, name, "compatible", "riscv,imsics");
> +
> + qemu_fdt_setprop_cell(fdt, name, "#interrupt-cells", 0);
> + qemu_fdt_setprop(fdt, name, "interrupt-controller", NULL, 0);
> + qemu_fdt_setprop(fdt, name, "msi-controller", NULL, 0);
> + qemu_fdt_setprop(fdt, name, "interrupts-extended",
> + imsic_cells, sizeof(uint32_t) * cpus * 2);
> + qemu_fdt_setprop_sized_cells(fdt, name, "reg", 2, mem->base, 2,
> mem->size);
> + qemu_fdt_setprop_cell(fdt, name, "riscv,num-ids", TT_IRQCHIP_NUM_MSIS);
> +
> + if (imsic_guest_bits) {
> + qemu_fdt_setprop_cell(fdt, name, "riscv,guest-index-bits",
> + imsic_guest_bits);
> + }
> + qemu_fdt_setprop_cell(fdt, name, "phandle", msi_phandle);
> +}
> +
> +static void create_fdt_one_aplic(void *fdt,
> + const MemMapEntry *mem,
> + uint32_t msi_phandle,
> + uint32_t *intc_phandles,
> + uint32_t aplic_phandle,
> + uint32_t aplic_child_phandle,
> + int irq_line, int num_harts)
> +{
> + g_autofree char *name =
> + g_strdup_printf("/soc/interrupt-controller@%"HWADDR_PRIX, mem->base);
> + g_autofree uint32_t *aplic_cells = g_new0(uint32_t, num_harts * 2);
> +
> + for (int cpu = 0; cpu < num_harts; cpu++) {
> + aplic_cells[cpu * 2 + 0] = cpu_to_be32(intc_phandles[cpu]);
> + aplic_cells[cpu * 2 + 1] = cpu_to_be32(irq_line);
> + }
> +
> + qemu_fdt_add_subnode(fdt, name);
> + qemu_fdt_setprop_string(fdt, name, "compatible", "riscv,aplic");
> + qemu_fdt_setprop_cell(fdt, name, "#address-cells", 0);
> + qemu_fdt_setprop_cell(fdt, name, "#interrupt-cells", 2);
> + qemu_fdt_setprop(fdt, name, "interrupt-controller", NULL, 0);
> +
> + qemu_fdt_setprop(fdt, name, "interrupts-extended",
> + aplic_cells, num_harts * sizeof(uint32_t) * 2);
> + qemu_fdt_setprop_cell(fdt, name, "msi-parent", msi_phandle);
> +
> + qemu_fdt_setprop_sized_cells(fdt, name, "reg", 2, mem->base, 2,
> mem->size);
> + qemu_fdt_setprop_cell(fdt, name, "riscv,num-sources",
> + TT_IRQCHIP_NUM_SOURCES);
> +
> + if (aplic_child_phandle) {
> + qemu_fdt_setprop_cell(fdt, name, "riscv,children",
> + aplic_child_phandle);
> + qemu_fdt_setprop_cells(fdt, name, "riscv,delegation",
> + aplic_child_phandle, 1,
> TT_IRQCHIP_NUM_SOURCES);
> + }
> +
> + qemu_fdt_setprop_cell(fdt, name, "phandle", aplic_phandle);
> +}
> +
> +static void create_fdt_pmu(TTAtlantisState *s)
> +{
> + char pmu_name[] = "/pmu";
> + void *fdt = MACHINE(s)->fdt;
> + RISCVCPU *hart = &s->soc.harts[0];
> +
> + qemu_fdt_add_subnode(fdt, pmu_name);
> + qemu_fdt_setprop_string(fdt, pmu_name, "compatible", "riscv,pmu");
> + riscv_pmu_generate_fdt_node(fdt, hart->pmu_avail_ctrs, pmu_name);
> +}
> +
> +static void create_fdt_cpu(TTAtlantisState *s, const MemMapEntry *memmap,
> + uint32_t aplic_s_phandle,
> + uint32_t imsic_s_phandle)
> +{
> + MachineState *ms = MACHINE(s);
> + void *fdt = MACHINE(s)->fdt;
> + g_autofree uint32_t *intc_phandles = NULL;
> +
> + qemu_fdt_add_subnode(fdt, "/cpus");
> + qemu_fdt_setprop_cell(fdt, "/cpus", "timebase-frequency",
> + TT_ACLINT_TIMEBASE_FREQ);
> + qemu_fdt_setprop_cell(fdt, "/cpus", "#size-cells", 0x0);
> + qemu_fdt_setprop_cell(fdt, "/cpus", "#address-cells", 0x1);
> +
> + intc_phandles = g_new0(uint32_t, ms->smp.cpus);
> +
> + create_fdt_cpus(s, intc_phandles);
> +
> + create_fdt_memory(s);
> +
> + create_fdt_aclint(s, intc_phandles);
> +
> + uint32_t imsic_guest_bits = imsic_num_bits(TT_IRQCHIP_GUESTS + 1);
> +
> + /* M-level IMSIC node */
> + uint32_t msi_m_phandle = next_phandle();
> + create_fdt_one_imsic(fdt, &s->memmap[TT_ATL_MIMSIC], ms->smp.cpus,
> + intc_phandles, msi_m_phandle,
> + IRQ_M_EXT, imsic_guest_bits);
> +
> + /* S-level IMSIC node */
> + create_fdt_one_imsic(fdt, &s->memmap[TT_ATL_SIMSIC], ms->smp.cpus,
> + intc_phandles, imsic_s_phandle,
> + IRQ_S_EXT, imsic_guest_bits);
> +
> + uint32_t aplic_m_phandle = next_phandle();
> +
> + /* M-level APLIC node */
> + create_fdt_one_aplic(fdt, &s->memmap[TT_ATL_MAPLIC],
> + msi_m_phandle, intc_phandles,
> + aplic_m_phandle, aplic_s_phandle,
> + IRQ_M_EXT, s->soc.num_harts);
> +
> + /* S-level APLIC node */
> + create_fdt_one_aplic(fdt, &s->memmap[TT_ATL_SAPLIC],
> + imsic_s_phandle, intc_phandles,
> + aplic_s_phandle, 0,
> + IRQ_S_EXT, s->soc.num_harts);
> +}
> +
> +static void create_fdt_uart(void *fdt, const MemMapEntry *mem, int irq,
> + int irqchip_phandle)
> +{
> + g_autofree char *name = g_strdup_printf("/soc/serial@%"HWADDR_PRIX,
> + mem->base);
> +
> + qemu_fdt_add_subnode(fdt, name);
> + qemu_fdt_setprop_string(fdt, name, "compatible", "ns16550a");
> + qemu_fdt_setprop_sized_cells(fdt, name, "reg", 2, mem->base, 2,
> mem->size);
> + qemu_fdt_setprop_cell(fdt, name, "reg-shift", 2);
> + qemu_fdt_setprop_cell(fdt, name, "reg-io-width", 4);
> + qemu_fdt_setprop_cell(fdt, name, "clock-frequency", 3686400);
> + qemu_fdt_setprop_cell(fdt, name, "interrupt-parent", irqchip_phandle);
> + qemu_fdt_setprop_cells(fdt, name, "interrupts", irq, 0x4);
> +
> + qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", name);
> + qemu_fdt_setprop_string(fdt, "/aliases", "serial0", name);
> +}
> +
> +static void create_fdt_rng(void *fdt)
> +{
> + uint8_t rng_seed[32];
> +
> + qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
> + qemu_fdt_setprop(fdt, "/chosen", "rng-seed", rng_seed, sizeof(rng_seed));
> +}
> +
> +static void finalize_fdt(TTAtlantisState *s)
> +{
> + uint32_t aplic_s_phandle = next_phandle();
> + uint32_t imsic_s_phandle = next_phandle();
> + void *fdt = MACHINE(s)->fdt;
> +
> + create_fdt_cpu(s, s->memmap, aplic_s_phandle, imsic_s_phandle);
> +
> + /*
> + * We want to do this, but the Linux aplic driver was broken before v6.16
> + *
> + * qemu_fdt_setprop_cell(MACHINE(s)->fdt, "/soc", "interrupt-parent",
> + * aplic_s_phandle);
> + */
> +
> + create_fdt_uart(fdt, &s->memmap[TT_ATL_UART1], TT_ATL_UART1_IRQ,
> + aplic_s_phandle);
> +}
> +
> +static void create_fdt(TTAtlantisState *s)
> +{
> + MachineState *ms = MACHINE(s);
> + void *fdt;
> +
> + fdt = create_device_tree(&s->fdt_size);
> + if (!fdt) {
> + error_report("create_device_tree() failed");
> + exit(1);
> + }
> + ms->fdt = fdt;
> +
> + qemu_fdt_setprop_string(fdt, "/", "model",
> + "Tenstorrent Atlantis RISC-V Machine");
> + qemu_fdt_setprop_string(fdt, "/", "compatible", "tenstorrent,atlantis");
> + qemu_fdt_setprop_cell(fdt, "/", "#size-cells", 0x2);
> + qemu_fdt_setprop_cell(fdt, "/", "#address-cells", 0x2);
> +
> + qemu_fdt_add_subnode(fdt, "/soc");
> + qemu_fdt_setprop(fdt, "/soc", "ranges", NULL, 0);
> + qemu_fdt_setprop_string(fdt, "/soc", "compatible", "simple-bus");
> + qemu_fdt_setprop_cell(fdt, "/soc", "#size-cells", 0x2);
> + qemu_fdt_setprop_cell(fdt, "/soc", "#address-cells", 0x2);
> +
> + qemu_fdt_add_subnode(fdt, "/chosen");
> +
> + create_fdt_rng(fdt);
> +
> + qemu_fdt_add_subnode(fdt, "/aliases");
> +
> + create_fdt_pmu(s);
> +}
> +
> +static void load_fdt(TTAtlantisState *s)
> +{
> + MachineState *ms = MACHINE(s);
> + char **node_path;
> + Error *err = NULL;
> +
> + ms->fdt = load_device_tree(ms->dtb, &s->fdt_size);
> + if (!ms->fdt) {
> + error_report("load_device_tree() failed");
> + exit(1);
> + }
> +
> + qemu_fdt_add_path(ms->fdt, "/chosen");
> +
> + /* Clear memory nodes and update with the specified RAM size */
> + node_path = qemu_fdt_node_unit_path(ms->fdt, "memory", &err);
> + if (err) {
> + warn_report_err(err);
> + } else {
> + for (int i = 0; node_path[i]; i++) {
> + qemu_fdt_nop_node(ms->fdt, node_path[i]);
Should we print a warning here to the user that we are doing this? I
would be confused (and annoyed) if QEMU deleted my memory regions and
I didn't know
> + }
> + g_strfreev(node_path);
> + }
> +
> + create_fdt_memory(s);
> +}
> +
> +static void tt_atlantis_machine_done(Notifier *notifier, void *data)
> +{
> + TTAtlantisState *s = container_of(notifier, TTAtlantisState,
> machine_done);
> + MachineState *machine = MACHINE(s);
> + hwaddr start_addr = s->memmap[TT_ATL_DDR_LO].base;
> + hwaddr mem_size;
> + target_ulong firmware_end_addr, kernel_start_addr;
> + const char *firmware_name = riscv_default_firmware_name(&s->soc);
> + uint64_t fdt_load_addr;
> + uint64_t kernel_entry;
> + RISCVBootInfo boot_info;
> +
> + /*
> + * A user provided dtb must include everything, including
> + * dynamic sysbus devices. Our FDT needs to be finalized.
> + */
> + if (machine->dtb == NULL) {
> + finalize_fdt(s);
Was expecting a finalise here :)
> + }
> +
> + mem_size = machine->ram_size;
> + if (mem_size > s->memmap[TT_ATL_DDR_LO].size) {
> + mem_size = s->memmap[TT_ATL_DDR_LO].size;
> + }
> + riscv_boot_info_init_discontig_mem(&boot_info, &s->soc,
> + s->memmap[TT_ATL_DDR_LO].base,
> + mem_size);
> +
> + firmware_end_addr = riscv_find_and_load_firmware(machine, &boot_info,
> + firmware_name,
> + &start_addr, NULL);
> +
> + kernel_start_addr = riscv_calc_kernel_start_addr(&boot_info,
> + firmware_end_addr);
> + if (machine->kernel_filename) {
> + riscv_load_kernel(machine, &boot_info, kernel_start_addr,
> + true, NULL);
> + }
> + kernel_entry = boot_info.image_low_addr;
> +
> + fdt_load_addr = riscv_compute_fdt_addr(s->memmap[TT_ATL_DDR_LO].base,
> + s->memmap[TT_ATL_DDR_LO].size,
> + machine, &boot_info);
> + riscv_load_fdt(fdt_load_addr, machine->fdt);
> +
> + /* load the reset vector */
> + riscv_setup_rom_reset_vec(machine, &s->soc, start_addr,
> + s->memmap[TT_ATL_BOOTROM].base,
> + s->memmap[TT_ATL_BOOTROM].size,
> + kernel_entry,
> + fdt_load_addr);
> +}
> +
> +static void tt_atlantis_machine_init(MachineState *machine)
> +{
> + TTAtlantisState *s = TT_ATLANTIS_MACHINE(machine);
> +
> + MemoryRegion *system_memory = get_system_memory();
> + MemoryRegion *ram_hi = g_new(MemoryRegion, 1);
> + MemoryRegion *ram_lo = g_new(MemoryRegion, 1);
> + MemoryRegion *bootrom = g_new(MemoryRegion, 1);
> + ram_addr_t lo_ram_size, hi_ram_size;
> + int hart_count = machine->smp.cpus;
> +
> + s->memmap = tt_atlantis_memmap;
> +
> + object_initialize_child(OBJECT(machine), "soc", &s->soc,
> + TYPE_RISCV_HART_ARRAY);
> + object_property_set_str(OBJECT(&s->soc), "cpu-type", machine->cpu_type,
> + &error_abort);
> + object_property_set_int(OBJECT(&s->soc), "hartid-base", 0,
> + &error_abort);
> + object_property_set_int(OBJECT(&s->soc), "num-harts", hart_count,
> + &error_abort);
> + object_property_set_int(OBJECT(&s->soc), "resetvec",
> + s->memmap[TT_ATL_BOOTROM].base,
> + &error_abort);
> + sysbus_realize(SYS_BUS_DEVICE(&s->soc), &error_fatal);
> +
> + s->irqchip = riscv_create_aia(true, TT_IRQCHIP_GUESTS,
> + TT_IRQCHIP_MIMSIC_STRIDE,
> + TT_IRQCHIP_NUM_SOURCES,
> + &s->memmap[TT_ATL_MAPLIC],
> + &s->memmap[TT_ATL_SAPLIC],
> + &s->memmap[TT_ATL_MIMSIC],
> + &s->memmap[TT_ATL_SIMSIC],
> + 0, 0, hart_count,
> + TT_IRQCHIP_NUM_MSIS,
> + TT_IRQCHIP_NUM_PRIO_BITS);
> +
> + riscv_aclint_mtimer_create(s->memmap[TT_ATL_ACLINT].base,
> + TT_ACLINT_MTIME_SIZE,
> + 0, hart_count,
> + TT_ACLINT_MTIMECMP,
> + TT_ACLINT_MTIME,
> + TT_ACLINT_TIMEBASE_FREQ, true);
> +
> + /* DDR */
> +
> + /* The high address covers all of RAM, the low address just the first
> 2GB */
> + lo_ram_size = s->memmap[TT_ATL_DDR_LO].size;
> + hi_ram_size = s->memmap[TT_ATL_DDR_HI].size;
> + if (machine->ram_size > hi_ram_size) {
What if machine->ram_size is less then s->memmap[TT_ATL_DDR_HI].size?
You will still allocate s->memmap[TT_ATL_DDR_HI].size instead of what
the user asked for. You then report what the user asked for in the DT,
so there is a bunch of wasted memory.
Memory is expensive these days, we can't waste it
Also, if the user asks for 2GB or less, you shouldn't create ram.high at all
Otherwise looks good
Alistair
> + char *sz = size_to_str(hi_ram_size);
> + error_report("RAM size is too large, maximum is %s", sz);
> + g_free(sz);
> + exit(EXIT_FAILURE);
> + }
> +
> + memory_region_init_alias(ram_lo, OBJECT(machine), "ram.low",
> machine->ram,
> + 0, lo_ram_size);
> + memory_region_init_alias(ram_hi, OBJECT(machine), "ram.high",
> machine->ram,
> + 0, hi_ram_size);
> + memory_region_add_subregion(system_memory,
> + s->memmap[TT_ATL_DDR_LO].base, ram_lo);
> + memory_region_add_subregion(system_memory,
> + s->memmap[TT_ATL_DDR_HI].base, ram_hi);
> +
> + /* Boot ROM */
> + memory_region_init_rom(bootrom, NULL, "tt-atlantis.bootrom",
> + s->memmap[TT_ATL_BOOTROM].size, &error_fatal);
> + memory_region_add_subregion(system_memory,
> s->memmap[TT_ATL_BOOTROM].base,
> + bootrom);
> +
> + /* UART1, the soc console (UART0 is for the boot microcontroller) */
> + serial_mm_init(system_memory, s->memmap[TT_ATL_UART1].base, 2,
> + qdev_get_gpio_in(s->irqchip, TT_ATL_UART1_IRQ),
> + 115200, serial_hd(0), DEVICE_LITTLE_ENDIAN);
> + /*
> + * Atlantis contains a DesignWare uart while the QEMU machine
> + * uses the serial_mm model with the base ns16550 register set.
> + * Linux's dw driver writes outside of serial_mm's 0x20 sized
> + * mapping and faults.
> + *
> + * Create an unimplemented device region so writes don't fault
> + * and reads return zero, which keeps Linux happy.
> + */
> + create_unimplemented_device("tt-atlantis.uart0",
> + s->memmap[TT_ATL_UART1].base,
> + s->memmap[TT_ATL_UART1].size);
> +
> + /* Load or create device tree */
> + if (machine->dtb) {
> + load_fdt(s);
> + } else {
> + create_fdt(s);
> + }
> +
> + s->machine_done.notify = tt_atlantis_machine_done;
> + qemu_add_machine_init_done_notifier(&s->machine_done);
> +}
> +
> +static void tt_atlantis_machine_class_init(ObjectClass *oc, const void *data)
> +{
> + MachineClass *mc = MACHINE_CLASS(oc);
> +
> + mc->desc = "Tenstorrent Atlantis RISC-V SoC";
> + mc->init = tt_atlantis_machine_init;
> + mc->max_cpus = 8;
> + mc->default_cpus = 8;
> + mc->default_ram_size = 4 * GiB;
> + mc->default_cpu_type = TYPE_RISCV_CPU_TT_ASCALON;
> + mc->block_default_type = IF_VIRTIO;
> + mc->no_cdrom = 1;
> + mc->default_ram_id = "tt_atlantis.ram";
> +}
> +
> +static const TypeInfo tt_atlantis_types[] = {
> + {
> + .name = MACHINE_TYPE_NAME("tt-atlantis"),
> + .parent = TYPE_MACHINE,
> + .class_init = tt_atlantis_machine_class_init,
> + .instance_size = sizeof(TTAtlantisState),
> + .interfaces = riscv64_machine_interfaces,
> + },
> +};
> +
> +DEFINE_TYPES(tt_atlantis_types)
> diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
> index 2518b04175fc..aaf029c9ed5e 100644
> --- a/hw/riscv/Kconfig
> +++ b/hw/riscv/Kconfig
> @@ -120,6 +120,16 @@ config SPIKE
> select RISCV_ACLINT
> select SIFIVE_PLIC
>
> +config TENSTORRENT
> + bool
> + default y
> + depends on RISCV64
> + select RISCV_ACLINT
> + select RISCV_APLIC
> + select RISCV_IMSIC
> + select SERIAL_MM
> + select DEVICE_TREE
> +
> config XIANGSHAN_KUNMINGHU
> bool
> default y
> diff --git a/hw/riscv/meson.build b/hw/riscv/meson.build
> index e53c180d0d10..026e79591f4b 100644
> --- a/hw/riscv/meson.build
> +++ b/hw/riscv/meson.build
> @@ -9,6 +9,7 @@ riscv_ss.add(when: 'CONFIG_SIFIVE_E', if_true:
> files('sifive_e.c'))
> riscv_ss.add(when: 'CONFIG_SIFIVE_U', if_true: files('sifive_u.c'))
> riscv_ss.add(when: 'CONFIG_SPIKE', if_true: files('spike.c'))
> riscv_ss.add(when: 'CONFIG_MICROCHIP_PFSOC', if_true:
> files('microchip_pfsoc.c'))
> +riscv_ss.add(when: 'CONFIG_TENSTORRENT', if_true: files('tt_atlantis.c'))
> riscv_ss.add(when: 'CONFIG_ACPI', if_true: files('virt-acpi-build.c'))
> riscv_ss.add(when: 'CONFIG_RISCV_IOMMU', if_true: files(
> 'riscv-iommu.c', 'riscv-iommu-pci.c', 'riscv-iommu-sys.c',
> 'riscv-iommu-hpm.c'))
> --
> 2.47.3
>
>
