From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: [PATCH 1/3] can: c_can: Update D_CAN TX and RX functions to 32 bit - fix Altera Cyclone access Date: Mon, 20 Jun 2016 10:00:28 +0200 Message-ID: <1466409630-6268-2-git-send-email-mkl@pengutronix.de> References: <1466409630-6268-1-git-send-email-mkl@pengutronix.de> Return-path: In-Reply-To: <1466409630-6268-1-git-send-email-mkl@pengutronix.de> Sender: stable-owner@vger.kernel.org To: netdev@vger.kernel.org Cc: davem@davemloft.net, linux-can@vger.kernel.org, kernel@pengutronix.de, Thor Thayer , stable@vger.kernel.org, Marc Kleine-Budde List-Id: linux-can.vger.kernel.org From: Thor Thayer When testing CAN write floods on Altera's CycloneV, the first 2 bytes are sometimes 0x00, 0x00 or corrupted instead of the values sent. Also observed bytes 4 & 5 were corrupted in some cases. The D_CAN Data registers are 32 bits and changing from 16 bit writes to 32 bit writes fixes the problem. Testing performed on Altera CycloneV (D_CAN). Requesting tests on other C_CAN & D_CAN platforms. Reported-by: Richard Andrysek Signed-off-by: Thor Thayer Cc: Signed-off-by: Marc Kleine-Budde --- drivers/net/can/c_can/c_can.c | 38 +++++++++++++++++++++++++++++++------- 1 file changed, 31 insertions(+), 7 deletions(-) diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index f91b094288da..e3dccd3200d5 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -332,9 +332,23 @@ static void c_can_setup_tx_object(struct net_device *dev, int iface, priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), ctrl); - for (i = 0; i < frame->can_dlc; i += 2) { - priv->write_reg(priv, C_CAN_IFACE(DATA1_REG, iface) + i / 2, - frame->data[i] | (frame->data[i + 1] << 8)); + if (priv->type == BOSCH_D_CAN) { + u32 data = 0, dreg = C_CAN_IFACE(DATA1_REG, iface); + + for (i = 0; i < frame->can_dlc; i += 4, dreg += 2) { + data = (u32)frame->data[i]; + data |= (u32)frame->data[i + 1] << 8; + data |= (u32)frame->data[i + 2] << 16; + data |= (u32)frame->data[i + 3] << 24; + priv->write_reg32(priv, dreg, data); + } + } else { + for (i = 0; i < frame->can_dlc; i += 2) { + priv->write_reg(priv, + C_CAN_IFACE(DATA1_REG, iface) + i / 2, + frame->data[i] | + (frame->data[i + 1] << 8)); + } } } @@ -402,10 +416,20 @@ static int c_can_read_msg_object(struct net_device *dev, int iface, u32 ctrl) } else { int i, dreg = C_CAN_IFACE(DATA1_REG, iface); - for (i = 0; i < frame->can_dlc; i += 2, dreg ++) { - data = priv->read_reg(priv, dreg); - frame->data[i] = data; - frame->data[i + 1] = data >> 8; + if (priv->type == BOSCH_D_CAN) { + for (i = 0; i < frame->can_dlc; i += 4, dreg += 2) { + data = priv->read_reg32(priv, dreg); + frame->data[i] = data; + frame->data[i + 1] = data >> 8; + frame->data[i + 2] = data >> 16; + frame->data[i + 3] = data >> 24; + } + } else { + for (i = 0; i < frame->can_dlc; i += 2, dreg++) { + data = priv->read_reg(priv, dreg); + frame->data[i] = data; + frame->data[i + 1] = data >> 8; + } } } -- 2.8.1