| Message ID | 20230622175200.74033-1-fido_max@inbox.ru (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2,1/1] net: axienet: Move reset before DMA detection | expand |
On Thu, 2023-06-22 at 20:52 +0300, Maxim Kochetkov wrote: > DMA detection will fail if axinet was started before (by boot loader, > boot ROM, etc). In this state axinet will not start properly. > XAXIDMA_TX_CDESC_OFFSET + 4 register (MM2S_CURDESC_MSB) is used to > detect > 64 DMA capability here. But datasheet says: When DMACR.RS is 1 > (axinet is in enabled state), CURDESC_PTR becomes Read Only (RO) and > is used to fetch the first descriptor. So iowrite32()/ioread32() > trick > to this register to detect DMA will not work. > So move axinet reset before DMA detection. > > Fixes: 04cc2da39698 ("net: axienet: reset core on initialization > prior to MDIO access") > Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru> > Reviewed-by: Robert Hancock <robert.hancock@calian.com> > --- > drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > index 3e310b55bce2..734822321e0a 100644 > --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > @@ -2042,6 +2042,11 @@ static int axienet_probe(struct > platform_device *pdev) > goto cleanup_clk; > } > > + /* Reset core now that clocks are enabled, prior to accessing > MDIO */ > + ret = __axienet_device_reset(lp); > + if (ret) > + goto cleanup_clk; > + > /* Autodetect the need for 64-bit DMA pointers. > * When the IP is configured for a bus width bigger than 32 > bits, > * writing the MSB registers is mandatory, even if they are > all 0. > @@ -2096,11 +2101,6 @@ static int axienet_probe(struct > platform_device *pdev) > lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD; > lp->coalesce_usec_tx = XAXIDMA_DFT_TX_USEC; > > - /* Reset core now that clocks are enabled, prior to accessing > MDIO */ > - ret = __axienet_device_reset(lp); > - if (ret) > - goto cleanup_clk; > - > ret = axienet_mdio_setup(lp); > if (ret) > dev_warn(&pdev->dev, > -- > 2.40.1 >
> -----Original Message----- > From: Maxim Kochetkov <fido_max@inbox.ru> > Sent: Thursday, June 22, 2023 11:22 PM > To: netdev@vger.kernel.org > Cc: Maxim Kochetkov <fido_max@inbox.ru>; Pandey, Radhey Shyam > <radhey.shyam.pandey@amd.com>; David S. Miller > <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub > Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Simek, > Michal <michal.simek@amd.com>; Andrew Lunn <andrew@lunn.ch>; Robert > Hancock <robert.hancock@calian.com>; linux-arm- > kernel@lists.infradead.org; linux-kernel@vger.kernel.org > Subject: [PATCH v2 1/1] net: axienet: Move reset before DMA detection > > DMA detection will fail if axinet was started before (by boot loader, :%s/axinet/axienet/g > boot ROM, etc). In this state axinet will not start properly. > XAXIDMA_TX_CDESC_OFFSET + 4 register (MM2S_CURDESC_MSB) is used to > detect > 64 DMA capability here. But datasheet says: When DMACR.RS is 1 > (axinet is in enabled state), CURDESC_PTR becomes Read Only (RO) and > is used to fetch the first descriptor. So iowrite32()/ioread32() trick > to this register to detect DMA will not work. > So move axinet reset before DMA detection. > > Fixes: 04cc2da39698 ("net: axienet: reset core on initialization prior to MDIO Is this fixes tag correct ? I think the failure is introduced after f735c40ed93c net: axienet: Autodetect 64-bit DMA capability? > access") > Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru> > --- > drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > index 3e310b55bce2..734822321e0a 100644 > --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > @@ -2042,6 +2042,11 @@ static int axienet_probe(struct platform_device > *pdev) > goto cleanup_clk; > } > > + /* Reset core now that clocks are enabled, prior to accessing MDIO > */ > + ret = __axienet_device_reset(lp); > + if (ret) > + goto cleanup_clk; > + > /* Autodetect the need for 64-bit DMA pointers. > * When the IP is configured for a bus width bigger than 32 bits, > * writing the MSB registers is mandatory, even if they are all 0. > @@ -2096,11 +2101,6 @@ static int axienet_probe(struct platform_device > *pdev) > lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD; > lp->coalesce_usec_tx = XAXIDMA_DFT_TX_USEC; > > - /* Reset core now that clocks are enabled, prior to accessing MDIO > */ > - ret = __axienet_device_reset(lp); > - if (ret) > - goto cleanup_clk; > - > ret = axienet_mdio_setup(lp); > if (ret) > dev_warn(&pdev->dev, > -- > 2.40.1
On 22.06.2023 21:43, Pandey, Radhey Shyam wrote: >> DMA detection will fail if axinet was started before (by boot loader, > > :%s/axinet/axienet/g Sorry about that. I will fix it in v3. > >> boot ROM, etc). In this state axinet will not start properly. >> XAXIDMA_TX_CDESC_OFFSET + 4 register (MM2S_CURDESC_MSB) is used to >> detect >> 64 DMA capability here. But datasheet says: When DMACR.RS is 1 >> (axinet is in enabled state), CURDESC_PTR becomes Read Only (RO) and >> is used to fetch the first descriptor. So iowrite32()/ioread32() trick >> to this register to detect DMA will not work. >> So move axinet reset before DMA detection. >> >> Fixes: 04cc2da39698 ("net: axienet: reset core on initialization prior to MDIO > > Is this fixes tag correct ? I think the failure is introduced after > f735c40ed93c net: axienet: Autodetect 64-bit DMA capability? Yes of course. I will fix it in v3.
> + /* Reset core now that clocks are enabled, prior to accessing MDIO */ > + ret = __axienet_device_reset(lp); > + if (ret) > + goto cleanup_clk; > + > /* Autodetect the need for 64-bit DMA pointers. I would say the comment is now not fully correct. It probably should be extended to include 64 bit DMA. Andrew
On 22.06.2023 22:18, Andrew Lunn wrote: >> + /* Reset core now that clocks are enabled, prior to accessing MDIO */ >> + ret = __axienet_device_reset(lp); >> + if (ret) >> + goto cleanup_clk; >> + >> /* Autodetect the need for 64-bit DMA pointers. > > I would say the comment is now not fully correct. It probably should > be extended to include 64 bit DMA. Fixed in v4
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 3e310b55bce2..734822321e0a 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -2042,6 +2042,11 @@ static int axienet_probe(struct platform_device *pdev) goto cleanup_clk; } + /* Reset core now that clocks are enabled, prior to accessing MDIO */ + ret = __axienet_device_reset(lp); + if (ret) + goto cleanup_clk; + /* Autodetect the need for 64-bit DMA pointers. * When the IP is configured for a bus width bigger than 32 bits, * writing the MSB registers is mandatory, even if they are all 0. @@ -2096,11 +2101,6 @@ static int axienet_probe(struct platform_device *pdev) lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD; lp->coalesce_usec_tx = XAXIDMA_DFT_TX_USEC; - /* Reset core now that clocks are enabled, prior to accessing MDIO */ - ret = __axienet_device_reset(lp); - if (ret) - goto cleanup_clk; - ret = axienet_mdio_setup(lp); if (ret) dev_warn(&pdev->dev,
DMA detection will fail if axinet was started before (by boot loader, boot ROM, etc). In this state axinet will not start properly. XAXIDMA_TX_CDESC_OFFSET + 4 register (MM2S_CURDESC_MSB) is used to detect 64 DMA capability here. But datasheet says: When DMACR.RS is 1 (axinet is in enabled state), CURDESC_PTR becomes Read Only (RO) and is used to fetch the first descriptor. So iowrite32()/ioread32() trick to this register to detect DMA will not work. So move axinet reset before DMA detection. Fixes: 04cc2da39698 ("net: axienet: reset core on initialization prior to MDIO access") Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru> --- drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)