tt_d2d.h File Reference

Tenstorrent Grendel die-to-die (D2D) firmware loading APIs. More...

#include <stddef.h>
#include <stdint.h>
#include <zephyr/device.h>
#include <zephyr/kernel.h>

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Functions
int	tt_d2d_reset_release (const struct device *dev)
	Deassert a D2D tile's subsystem resets, in hardware order.
int	tt_d2d_load_fw (const struct device *dev, const uint8_t *img, size_t img_size)
	Load firmware into a D2D tile, leaving the Rocket halted.
int	tt_d2d_start (const struct device *dev)
	Release a D2D tile's Rocket so loaded firmware begins executing.
int	tt_d2d_wait_link (const struct device *dev, k_timeout_t timeout)
	Wait for this end of the link to finish training.
uint32_t	tt_d2d_progress_code (const struct device *dev)
	Firmware training progress code (drop d2d_api_fw_progress_codes.h).

Detailed Description

Tenstorrent Grendel die-to-die (D2D) firmware loading APIs.

Sequence: reset_release (before the CCE PLL switch, straps sample the current clock) -> load_fw (Rocket stays halted) -> start (both ends close together; sideband sync is off on emu) -> wait_link.

Cold reset and firewalls are chip-wide and are not done here. Until they are, load_fw() fails the SRAM probe with -ENODEV.

Function Documentation

tt_d2d_load_fw()

int tt_d2d_load_fw	(	const struct device *	dev,
		const uint8_t *	img,
		size_t	img_size )

Load firmware into a D2D tile, leaving the Rocket halted.

Parameters

dev	D2D tile device
img	Firmware image
img_size	Size of img in bytes. Multiple of 4; must not overrun the configuration block at the top of SRAM.

Return values

0	on success
-EINVAL	if img is NULL, empty, or not a multiple of 4 bytes
-ENOSPC	if img would overrun the configuration block
-ENODEV	if the tile does not answer a write to its SRAM
-EIO	if the image read back from SRAM does not match img

tt_d2d_progress_code()

uint32_t tt_d2d_progress_code

(

const struct device *

dev

)

Firmware training progress code (drop d2d_api_fw_progress_codes.h).

Parameters

dev	D2D tile device

Returns

the firmware's current progress code, or 0 if none yet

tt_d2d_reset_release()

int tt_d2d_reset_release

(

const struct device *

dev

)

Deassert a D2D tile's subsystem resets, in hardware order.

Parameters

dev	D2D tile device

Return values

0	on success

tt_d2d_start()

int tt_d2d_start

(

const struct device *

dev

)

Release a D2D tile's Rocket so loaded firmware begins executing.

Parameters

dev	D2D tile device

Return values

0	on success

tt_d2d_wait_link()

int tt_d2d_wait_link	(	const struct device *	dev,
		k_timeout_t	timeout )

Wait for this end of the link to finish training.

Polls the firmware progress code in SRAM (link-layer status is not modelled on emu). Both ends must already have been started.

Parameters

dev	D2D tile device
timeout	How long to wait, or K_FOREVER

Return values

0	if the link trained
-EIO	if the firmware reported a training failure
-ETIMEDOUT	if it did neither