JEP106 has two vendor IDs for Tenstorrent. We will use Bank 16, company 33:

  ((16 - 1) << 7) | 33 = 0x7a1

As JEP106 requires registration to download, the number can confirmed by
looking at the OpenOCD sources[1].

Alternatively, referring to the JEDEC document the hex IDs are listed with the
parity (MSB) bit added. Company 33 has hex 0xa1:

 ((16 - 1) << 7) | (0xa1 & ~0x80) = 0x7a1

Add it to the Ascalon CPU definition as the mvendorid CSR.

[1] https://github.com/openocd-org/openocd/blob/1ebff3ab33c77e3f8fb4e1ddda262b606b572af1/src/helper/jep106.inc#L1935

Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Daniel Henrique Barboza <daniel.barboza@oss.qualcomm.com>
Reviewed-by: Michael Ellerman <mpe@oss.tenstorrent.com>
---
v2: Add r-b, and add mpe's explanation as a public way to check.
---
 target/riscv/cpu_vendorid.h | 2 ++
 target/riscv/cpu.c          | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/target/riscv/cpu_vendorid.h b/target/riscv/cpu_vendorid.h
index f1ffc66542a0..751a13aace47 100644
--- a/target/riscv/cpu_vendorid.h
+++ b/target/riscv/cpu_vendorid.h
@@ -8,4 +8,6 @@
 #define VEYRON_V1_MIMPID        0x111
 #define VEYRON_V1_MVENDORID     0x61f
 
+#define TENSTORRENT_VENDOR_ID   0x7a1
+
 #endif /*  TARGET_RISCV_CPU_VENDORID_H */
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index ffd98e8eed46..81ad21a6bf73 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -3190,6 +3190,8 @@ static const TypeInfo riscv_cpu_type_infos[] = {
         .cfg.ext_svnapot = true,
         .cfg.ext_svpbmt = true,
 
+        .cfg.mvendorid = TENSTORRENT_VENDOR_ID,
+
         .cfg.max_satp_mode = VM_1_10_SV57,
     ),
 
-- 
2.47.3