Message ID | 1612807436-5238-3-git-send-email-piyush.mehta@xilinx.com |
---|---|
State | New |
Headers | show |
Series | ata: ahci: ceva: Update the driver to support xilinx GT phy | expand |
On 2/8/21 7:03 PM, Piyush Mehta wrote: > SATA controller used in Xilinx ZynqMP platform uses xilinx GT phy > which has 4 GT lanes and can be used by 4 peripherals at a time. > SATA controller uses 1 GT phy lane among the 4 GT lanes. To configure > the GT lane for the SATA controller, the below sequence is expected. > > 1. Assert the SATA controller reset. > 2. Configure the xilinx GT phy lane for SATA controller (phy_init). > 3. De-assert the SATA controller reset. > 4. Wait for PLL of the GT lane used by SATA to be locked (phy_power_on). > > The ahci_platform_enable_resources() by default does the phy_init() > and phy_power_on() but the default sequence doesn't work with Xilinx > platforms. Because of this reason, updated the driver to support the > new sequence. > > Added cevapriv->rst check, for backward compatibility with the older > sequence. If the reset controller is not available, then the SATA > controller will configure with the older sequences. > > Signed-off-by: Piyush Mehta <piyush.mehta@xilinx.com> > --- > drivers/ata/ahci_ceva.c | 43 ++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 40 insertions(+), 3 deletions(-) > > diff --git a/drivers/ata/ahci_ceva.c b/drivers/ata/ahci_ceva.c > index b10fd4c..b980218 100644 > --- a/drivers/ata/ahci_ceva.c > +++ b/drivers/ata/ahci_ceva.c > @@ -12,6 +12,7 @@ > #include <linux/module.h> > #include <linux/of_device.h> > #include <linux/platform_device.h> > +#include <linux/reset.h> > #include "ahci.h" > > /* Vendor Specific Register Offsets */ > @@ -87,6 +88,7 @@ struct ceva_ahci_priv { > u32 axicc; > bool is_cci_enabled; > int flags; > + struct reset_control *rst; > }; > > static unsigned int ceva_ahci_read_id(struct ata_device *dev, > @@ -202,13 +204,48 @@ static int ceva_ahci_probe(struct platform_device *pdev) > > cevapriv->ahci_pdev = pdev; > > + cevapriv->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, > + NULL); > + if (IS_ERR(cevapriv->rst)) { > + if (PTR_ERR(cevapriv->rst) != -EPROBE_DEFER) > + dev_err(&pdev->dev, "failed to get reset: %ld\n", > + PTR_ERR(cevapriv->rst)); > + } nit: This can be handled via dev_err_probe() to simplify this logic here. It was added by a787e5400a1c ("driver core: add device probe log helper") but up to Jens if he wants this to be fixed. > + > hpriv = ahci_platform_get_resources(pdev, 0); > if (IS_ERR(hpriv)) > return PTR_ERR(hpriv); > > - rc = ahci_platform_enable_resources(hpriv); > - if (rc) > - return rc; > + if (!cevapriv->rst) { > + rc = ahci_platform_enable_resources(hpriv); > + if (rc) > + return rc; > + } else { > + int i; > + > + rc = ahci_platform_enable_clks(hpriv); > + if (rc) > + return rc; > + /* Assert the controller reset */ > + reset_control_assert(cevapriv->rst); > + > + for (i = 0; i < hpriv->nports; i++) { > + rc = phy_init(hpriv->phys[i]); > + if (rc) > + return rc; > + } > + > + /* De-assert the controller reset */ > + reset_control_deassert(cevapriv->rst); > + > + for (i = 0; i < hpriv->nports; i++) { > + rc = phy_power_on(hpriv->phys[i]); > + if (rc) { > + phy_exit(hpriv->phys[i]); > + return rc; > + } > + } > + } > > if (of_property_read_bool(np, "ceva,broken-gen2")) > cevapriv->flags = CEVA_FLAG_BROKEN_GEN2; > Acked-by: Michal Simek <michal.simek@xilinx.com> Jens: Can you please take a look at this patch if you see any other issue? Thanks, Michal
diff --git a/drivers/ata/ahci_ceva.c b/drivers/ata/ahci_ceva.c index b10fd4c..b980218 100644 --- a/drivers/ata/ahci_ceva.c +++ b/drivers/ata/ahci_ceva.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> +#include <linux/reset.h> #include "ahci.h" /* Vendor Specific Register Offsets */ @@ -87,6 +88,7 @@ struct ceva_ahci_priv { u32 axicc; bool is_cci_enabled; int flags; + struct reset_control *rst; }; static unsigned int ceva_ahci_read_id(struct ata_device *dev, @@ -202,13 +204,48 @@ static int ceva_ahci_probe(struct platform_device *pdev) cevapriv->ahci_pdev = pdev; + cevapriv->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, + NULL); + if (IS_ERR(cevapriv->rst)) { + if (PTR_ERR(cevapriv->rst) != -EPROBE_DEFER) + dev_err(&pdev->dev, "failed to get reset: %ld\n", + PTR_ERR(cevapriv->rst)); + } + hpriv = ahci_platform_get_resources(pdev, 0); if (IS_ERR(hpriv)) return PTR_ERR(hpriv); - rc = ahci_platform_enable_resources(hpriv); - if (rc) - return rc; + if (!cevapriv->rst) { + rc = ahci_platform_enable_resources(hpriv); + if (rc) + return rc; + } else { + int i; + + rc = ahci_platform_enable_clks(hpriv); + if (rc) + return rc; + /* Assert the controller reset */ + reset_control_assert(cevapriv->rst); + + for (i = 0; i < hpriv->nports; i++) { + rc = phy_init(hpriv->phys[i]); + if (rc) + return rc; + } + + /* De-assert the controller reset */ + reset_control_deassert(cevapriv->rst); + + for (i = 0; i < hpriv->nports; i++) { + rc = phy_power_on(hpriv->phys[i]); + if (rc) { + phy_exit(hpriv->phys[i]); + return rc; + } + } + } if (of_property_read_bool(np, "ceva,broken-gen2")) cevapriv->flags = CEVA_FLAG_BROKEN_GEN2;
SATA controller used in Xilinx ZynqMP platform uses xilinx GT phy which has 4 GT lanes and can be used by 4 peripherals at a time. SATA controller uses 1 GT phy lane among the 4 GT lanes. To configure the GT lane for the SATA controller, the below sequence is expected. 1. Assert the SATA controller reset. 2. Configure the xilinx GT phy lane for SATA controller (phy_init). 3. De-assert the SATA controller reset. 4. Wait for PLL of the GT lane used by SATA to be locked (phy_power_on). The ahci_platform_enable_resources() by default does the phy_init() and phy_power_on() but the default sequence doesn't work with Xilinx platforms. Because of this reason, updated the driver to support the new sequence. Added cevapriv->rst check, for backward compatibility with the older sequence. If the reset controller is not available, then the SATA controller will configure with the older sequences. Signed-off-by: Piyush Mehta <piyush.mehta@xilinx.com> --- drivers/ata/ahci_ceva.c | 43 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 40 insertions(+), 3 deletions(-)