| Message ID | 20241107-pcie-en7581-fixes-v1-3-af0c872323c7@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: mediatek-gen3: mtk_pcie_en7581_power_up code refactoring | expand |
On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > In order to make the code more readable, move phy and mac reset lines > assert/de-assert configuration in .power_up callback > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > --- > drivers/pci/controller/pcie-mediatek-gen3.c | 24 ++++++++++++++++-------- > 1 file changed, 16 insertions(+), 8 deletions(-) > > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c > index 8c8c733a145634cdbfefd339f4a692f25a6e24de..c0127d0fb4f059b9f9e816360130e183e8f0e990 100644 > --- a/drivers/pci/controller/pcie-mediatek-gen3.c > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c > @@ -867,6 +867,13 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie) > int err; > u32 val; > > + /* > + * The controller may have been left out of reset by the bootloader > + * so make sure that we get a clean start by asserting resets here. > + */ > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > + pcie->phy_resets); > + reset_control_assert(pcie->mac_reset); Add blank line here. > /* > * Wait for the time needed to complete the bulk assert in > * mtk_pcie_setup for EN7581 SoC. > @@ -941,6 +948,15 @@ static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie) > struct device *dev = pcie->dev; > int err; > > + /* > + * The controller may have been left out of reset by the bootloader > + * so make sure that we get a clean start by asserting resets here. > + */ > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > + pcie->phy_resets); > + reset_control_assert(pcie->mac_reset); > + usleep_range(10, 20); Unrelated to this patch, but since you're moving it, do you know what this delay is for? Can we add a #define and a spec citation for it? Is there a requirement that the PHY and MAC reset ordering be different for EN7581 vs other chips? EN7581: assert PHY reset assert MAC reset power on PHY deassert PHY reset deassert MAC reset others: assert PHY reset assert MAC reset deassert PHY reset power on PHY deassert MAC reset Is there one order that would work for both? > /* PHY power on and enable pipe clock */ > err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > if (err) { > @@ -1013,14 +1029,6 @@ static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie) > * counter since the bulk is shared. > */ > reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > - /* > - * The controller may have been left out of reset by the bootloader > - * so make sure that we get a clean start by asserting resets here. > - */ > - reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > - > - reset_control_assert(pcie->mac_reset); > - usleep_range(10, 20); > > /* Don't touch the hardware registers before power up */ > err = pcie->soc->power_up(pcie); > > -- > 2.47.0 >
> On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > In order to make the code more readable, move phy and mac reset lines > > assert/de-assert configuration in .power_up callback > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > --- > > drivers/pci/controller/pcie-mediatek-gen3.c | 24 ++++++++++++++++-------- > > 1 file changed, 16 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c > > index 8c8c733a145634cdbfefd339f4a692f25a6e24de..c0127d0fb4f059b9f9e816360130e183e8f0e990 100644 > > --- a/drivers/pci/controller/pcie-mediatek-gen3.c > > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c > > @@ -867,6 +867,13 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie) > > int err; > > u32 val; > > > > + /* > > + * The controller may have been left out of reset by the bootloader > > + * so make sure that we get a clean start by asserting resets here. > > + */ > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > + pcie->phy_resets); > > + reset_control_assert(pcie->mac_reset); > > Add blank line here. ack, I will fix it. > > > /* > > * Wait for the time needed to complete the bulk assert in > > * mtk_pcie_setup for EN7581 SoC. > > @@ -941,6 +948,15 @@ static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie) > > struct device *dev = pcie->dev; > > int err; > > > > + /* > > + * The controller may have been left out of reset by the bootloader > > + * so make sure that we get a clean start by asserting resets here. > > + */ > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > + pcie->phy_resets); > > + reset_control_assert(pcie->mac_reset); > > + usleep_range(10, 20); > > Unrelated to this patch, but since you're moving it, do you know what > this delay is for? Can we add a #define and a spec citation for it? I am not sure about it, this was already there. @Jianjun Wang: any input on it? > > Is there a requirement that the PHY and MAC reset ordering be > different for EN7581 vs other chips? > > EN7581: > > assert PHY reset > assert MAC reset > power on PHY > deassert PHY reset > deassert MAC reset > > others: > > assert PHY reset > assert MAC reset > deassert PHY reset > power on PHY > deassert MAC reset > > Is there one order that would work for both? EN7581 requires to run phy_init()/phy_power_on() before deassert PHY reset lines. Regards, Lorenzo > > > /* PHY power on and enable pipe clock */ > > err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > > if (err) { > > @@ -1013,14 +1029,6 @@ static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie) > > * counter since the bulk is shared. > > */ > > reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > > - /* > > - * The controller may have been left out of reset by the bootloader > > - * so make sure that we get a clean start by asserting resets here. > > - */ > > - reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); > > - > > - reset_control_assert(pcie->mac_reset); > > - usleep_range(10, 20); > > > > /* Don't touch the hardware registers before power up */ > > err = pcie->soc->power_up(pcie); > > > > -- > > 2.47.0 > >
On Thu, Nov 07, 2024 at 05:08:55PM +0100, Lorenzo Bianconi wrote: > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > In order to make the code more readable, move phy and mac reset lines > > > assert/de-assert configuration in .power_up callback > > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > ... > > Is there a requirement that the PHY and MAC reset ordering be > > different for EN7581 vs other chips? > > > > EN7581: > > > > assert PHY reset > > assert MAC reset > > power on PHY > > deassert PHY reset > > deassert MAC reset > > > > others: > > > > assert PHY reset > > assert MAC reset > > deassert PHY reset > > power on PHY > > deassert MAC reset > > > > Is there one order that would work for both? > > EN7581 requires to run phy_init()/phy_power_on() before deassert PHY reset > lines. And the other chips require the PHY power-on to be *after* deasserting PHY reset?
On Nov 07, Bjorn Helgaas wrote: > On Thu, Nov 07, 2024 at 05:08:55PM +0100, Lorenzo Bianconi wrote: > > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > > In order to make the code more readable, move phy and mac reset lines > > > > assert/de-assert configuration in .power_up callback > > > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > ... > > > > Is there a requirement that the PHY and MAC reset ordering be > > > different for EN7581 vs other chips? > > > > > > EN7581: > > > > > > assert PHY reset > > > assert MAC reset > > > power on PHY > > > deassert PHY reset > > > deassert MAC reset > > > > > > others: > > > > > > assert PHY reset > > > assert MAC reset > > > deassert PHY reset > > > power on PHY > > > deassert MAC reset > > > > > > Is there one order that would work for both? > > > > EN7581 requires to run phy_init()/phy_power_on() before deassert PHY reset > > lines. > > And the other chips require the PHY power-on to be *after* deasserting > PHY reset? I am not sure about it, this is the only Airoha device I have. Regards, Lorenzo
On Thu, 2024-11-07 at 17:08 +0100, Lorenzo Bianconi wrote: > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > In order to make the code more readable, move phy and mac reset > > > lines > > > assert/de-assert configuration in .power_up callback > > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > > > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > > --- > > > drivers/pci/controller/pcie-mediatek-gen3.c | 24 > > > ++++++++++++++++-------- > > > 1 file changed, 16 insertions(+), 8 deletions(-) > > > > > > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c > > > b/drivers/pci/controller/pcie-mediatek-gen3.c > > > index > > > 8c8c733a145634cdbfefd339f4a692f25a6e24de..c0127d0fb4f059b9f9e8163 > > > 60130e183e8f0e990 100644 > > > --- a/drivers/pci/controller/pcie-mediatek-gen3.c > > > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c > > > @@ -867,6 +867,13 @@ static int mtk_pcie_en7581_power_up(struct > > > mtk_gen3_pcie *pcie) > > > int err; > > > u32 val; > > > > > > + /* > > > + * The controller may have been left out of reset by the > > > bootloader > > > + * so make sure that we get a clean start by asserting resets > > > here. > > > + */ > > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > + pcie->phy_resets); > > > + reset_control_assert(pcie->mac_reset); > > > > Add blank line here. > > ack, I will fix it. > > > > > > /* > > > * Wait for the time needed to complete the bulk assert in > > > * mtk_pcie_setup for EN7581 SoC. > > > @@ -941,6 +948,15 @@ static int mtk_pcie_power_up(struct > > > mtk_gen3_pcie *pcie) > > > struct device *dev = pcie->dev; > > > int err; > > > > > > + /* > > > + * The controller may have been left out of reset by the > > > bootloader > > > + * so make sure that we get a clean start by asserting resets > > > here. > > > + */ > > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > + pcie->phy_resets); > > > + reset_control_assert(pcie->mac_reset); > > > + usleep_range(10, 20); > > > > Unrelated to this patch, but since you're moving it, do you know > > what > > this delay is for? Can we add a #define and a spec citation for > > it? > > I am not sure about it, this was already there. > @Jianjun Wang: any input on it? This delay is used to ensure the reset is effective. A delay of 10us should be sufficient in this scenario. > > > > > Is there a requirement that the PHY and MAC reset ordering be > > different for EN7581 vs other chips? > > > > EN7581: > > > > assert PHY reset > > assert MAC reset > > power on PHY > > deassert PHY reset > > deassert MAC reset > > > > others: > > > > assert PHY reset > > assert MAC reset > > deassert PHY reset > > power on PHY > > deassert MAC reset > > > > Is there one order that would work for both? > > EN7581 requires to run phy_init()/phy_power_on() before deassert PHY > reset > lines. > > Regards, > Lorenzo > > > > > > /* PHY power on and enable pipe clock */ > > > err = reset_control_bulk_deassert(pcie->soc- > > > >phy_resets.num_resets, pcie->phy_resets); > > > if (err) { > > > @@ -1013,14 +1029,6 @@ static int mtk_pcie_setup(struct > > > mtk_gen3_pcie *pcie) > > > * counter since the bulk is shared. > > > */ > > > reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, > > > pcie->phy_resets); > > > - /* > > > - * The controller may have been left out of reset by the > > > bootloader > > > - * so make sure that we get a clean start by asserting resets > > > here. > > > - */ > > > - reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > pcie->phy_resets); > > > - > > > - reset_control_assert(pcie->mac_reset); > > > - usleep_range(10, 20); > > > > > > /* Don't touch the hardware registers before power up */ > > > err = pcie->soc->power_up(pcie); > > > > > > -- > > > 2.47.0 > > >
On Thu, 2024-11-07 at 10:21 -0600, Bjorn Helgaas wrote: > External email : Please do not click links or open attachments until > you have verified the sender or the content. > > > On Thu, Nov 07, 2024 at 05:08:55PM +0100, Lorenzo Bianconi wrote: > > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > > In order to make the code more readable, move phy and mac reset > > > > lines > > > > assert/de-assert configuration in .power_up callback > > > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > > > ... > > > Is there a requirement that the PHY and MAC reset ordering be > > > different for EN7581 vs other chips? > > > > > > EN7581: > > > > > > assert PHY reset > > > assert MAC reset > > > power on PHY > > > deassert PHY reset > > > deassert MAC reset > > > > > > others: > > > > > > assert PHY reset > > > assert MAC reset > > > deassert PHY reset > > > power on PHY > > > deassert MAC reset > > > > > > Is there one order that would work for both? > > > > EN7581 requires to run phy_init()/phy_power_on() before deassert > > PHY reset > > lines. > > And the other chips require the PHY power-on to be *after* > deasserting > PHY reset? For MediaTek's chips, the reset will clear all register values and reset the hardware state. Therefore, we can only initialize and power- on the MAC and PHY after deasserting their resets. Thanks.
> On Thu, 2024-11-07 at 17:08 +0100, Lorenzo Bianconi wrote: > > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > > In order to make the code more readable, move phy and mac reset > > > > lines > > > > assert/de-assert configuration in .power_up callback > > > > (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > > > > > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > > > --- > > > > drivers/pci/controller/pcie-mediatek-gen3.c | 24 > > > > ++++++++++++++++-------- > > > > 1 file changed, 16 insertions(+), 8 deletions(-) > > > > > > > > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c > > > > b/drivers/pci/controller/pcie-mediatek-gen3.c > > > > index > > > > 8c8c733a145634cdbfefd339f4a692f25a6e24de..c0127d0fb4f059b9f9e8163 > > > > 60130e183e8f0e990 100644 > > > > --- a/drivers/pci/controller/pcie-mediatek-gen3.c > > > > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c > > > > @@ -867,6 +867,13 @@ static int mtk_pcie_en7581_power_up(struct > > > > mtk_gen3_pcie *pcie) > > > > int err; > > > > u32 val; > > > > > > > > + /* > > > > + * The controller may have been left out of reset by the > > > > bootloader > > > > + * so make sure that we get a clean start by asserting resets > > > > here. > > > > + */ > > > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > > + pcie->phy_resets); > > > > + reset_control_assert(pcie->mac_reset); > > > > > > Add blank line here. > > > > ack, I will fix it. > > > > > > > > > /* > > > > * Wait for the time needed to complete the bulk assert in > > > > * mtk_pcie_setup for EN7581 SoC. > > > > @@ -941,6 +948,15 @@ static int mtk_pcie_power_up(struct > > > > mtk_gen3_pcie *pcie) > > > > struct device *dev = pcie->dev; > > > > int err; > > > > > > > > + /* > > > > + * The controller may have been left out of reset by the > > > > bootloader > > > > + * so make sure that we get a clean start by asserting resets > > > > here. > > > > + */ > > > > + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > > + pcie->phy_resets); > > > > + reset_control_assert(pcie->mac_reset); > > > > + usleep_range(10, 20); > > > > > > Unrelated to this patch, but since you're moving it, do you know > > > what > > > this delay is for? Can we add a #define and a spec citation for > > > it? > > > > I am not sure about it, this was already there. > > @Jianjun Wang: any input on it? > > This delay is used to ensure the reset is effective. A delay of 10us > should be sufficient in this scenario. ack, so we can introduce a marco like: #define PCIE_RESET_TIME_US 10 ... usleep_range(PCIE_RESET_TIME_US, 2 * PCIE_RESET_TIME_US); what do you think? Regards, Lorenzo > > > > > > > > > Is there a requirement that the PHY and MAC reset ordering be > > > different for EN7581 vs other chips? > > > > > > EN7581: > > > > > > assert PHY reset > > > assert MAC reset > > > power on PHY > > > deassert PHY reset > > > deassert MAC reset > > > > > > others: > > > > > > assert PHY reset > > > assert MAC reset > > > deassert PHY reset > > > power on PHY > > > deassert MAC reset > > > > > > Is there one order that would work for both? > > > > EN7581 requires to run phy_init()/phy_power_on() before deassert PHY > > reset > > lines. > > > > Regards, > > Lorenzo > > > > > > > > > /* PHY power on and enable pipe clock */ > > > > err = reset_control_bulk_deassert(pcie->soc- > > > > >phy_resets.num_resets, pcie->phy_resets); > > > > if (err) { > > > > @@ -1013,14 +1029,6 @@ static int mtk_pcie_setup(struct > > > > mtk_gen3_pcie *pcie) > > > > * counter since the bulk is shared. > > > > */ > > > > reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, > > > > pcie->phy_resets); > > > > - /* > > > > - * The controller may have been left out of reset by the > > > > bootloader > > > > - * so make sure that we get a clean start by asserting resets > > > > here. > > > > - */ > > > > - reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, > > > > pcie->phy_resets); > > > > - > > > > - reset_control_assert(pcie->mac_reset); > > > > - usleep_range(10, 20); > > > > > > > > /* Don't touch the hardware registers before power up */ > > > > err = pcie->soc->power_up(pcie); > > > > > > > > -- > > > > 2.47.0 > > > >
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 8c8c733a145634cdbfefd339f4a692f25a6e24de..c0127d0fb4f059b9f9e816360130e183e8f0e990 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -867,6 +867,13 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie) int err; u32 val; + /* + * The controller may have been left out of reset by the bootloader + * so make sure that we get a clean start by asserting resets here. + */ + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, + pcie->phy_resets); + reset_control_assert(pcie->mac_reset); /* * Wait for the time needed to complete the bulk assert in * mtk_pcie_setup for EN7581 SoC. @@ -941,6 +948,15 @@ static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie) struct device *dev = pcie->dev; int err; + /* + * The controller may have been left out of reset by the bootloader + * so make sure that we get a clean start by asserting resets here. + */ + reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, + pcie->phy_resets); + reset_control_assert(pcie->mac_reset); + usleep_range(10, 20); + /* PHY power on and enable pipe clock */ err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); if (err) { @@ -1013,14 +1029,6 @@ static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie) * counter since the bulk is shared. */ reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); - /* - * The controller may have been left out of reset by the bootloader - * so make sure that we get a clean start by asserting resets here. - */ - reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, pcie->phy_resets); - - reset_control_assert(pcie->mac_reset); - usleep_range(10, 20); /* Don't touch the hardware registers before power up */ err = pcie->soc->power_up(pcie);
In order to make the code more readable, move phy and mac reset lines assert/de-assert configuration in .power_up callback (mtk_pcie_en7581_power_up/mtk_pcie_power_up). Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- drivers/pci/controller/pcie-mediatek-gen3.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-)