From: Pali Rohár pali@kernel.org
[ Upstream commit 2eab59cf0d2036a5a9e264f719b71c21ccf679c2 ]
When Marvell's rWTM firmware, which does not support the GET_RANDOM command, is used, kernel prints an error message hwrng: no data available every 10 seconds.
Fail probing of this driver if the rWTM firmware does not support the GET_RANDOM command.
Fixes: 389711b37493 ("firmware: Add Turris Mox rWTM firmware driver") Signed-off-by: Pali Rohár pali@kernel.org Signed-off-by: Marek Behún kabel@kernel.org Reviewed-by: Andrew Lunn andrew@lunn.ch Signed-off-by: Gregory CLEMENT gregory.clement@bootlin.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/turris-mox-rwtm.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)
diff --git a/drivers/firmware/turris-mox-rwtm.c b/drivers/firmware/turris-mox-rwtm.c index e22ad73d4c86..9a6cf5af27a3 100644 --- a/drivers/firmware/turris-mox-rwtm.c +++ b/drivers/firmware/turris-mox-rwtm.c @@ -247,6 +247,27 @@ static int mox_get_board_info(struct mox_rwtm *rwtm) return 0; }
+static int check_get_random_support(struct mox_rwtm *rwtm) +{ + struct armada_37xx_rwtm_tx_msg msg; + int ret; + + msg.command = MBOX_CMD_GET_RANDOM; + msg.args[0] = 1; + msg.args[1] = rwtm->buf_phys; + msg.args[2] = 4; + + ret = mbox_send_message(rwtm->mbox, &msg); + if (ret < 0) + return ret; + + ret = wait_for_completion_timeout(&rwtm->cmd_done, HZ / 2); + if (ret < 0) + return ret; + + return mox_get_status(MBOX_CMD_GET_RANDOM, rwtm->reply.retval); +} + static int mox_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait) { struct mox_rwtm *rwtm = (struct mox_rwtm *) rng->priv; @@ -338,6 +359,13 @@ static int turris_mox_rwtm_probe(struct platform_device *pdev) if (ret < 0) dev_warn(dev, "Cannot read board information: %i\n", ret);
+ ret = check_get_random_support(rwtm); + if (ret < 0) { + dev_notice(dev, + "Firmware does not support the GET_RANDOM command\n"); + goto free_channel; + } + rwtm->hwrng.name = DRIVER_NAME "_hwrng"; rwtm->hwrng.read = mox_hwrng_read; rwtm->hwrng.priv = (unsigned long) rwtm;