| Message ID | 20240224-pci-dbi-rework-v8-3-64c7fd0cfe64@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: dwc: ep: Fix DBI access failure for drivers requiring refclk from host | expand |
On Sat, Feb 24, 2024 at 12:24:09PM +0530, Manivannan Sadhasivam wrote: > For DWC glue drivers supporting PERST# (currently Qcom and Tegra194), some > of the DWC resources like eDMA should be cleaned up during the PERST# > assert time. > > So let's introduce a dw_pcie_ep_cleanup() API that could be called by these > drivers to cleanup the DWC specific resources. Currently, it just removes > eDMA. > > Reported-by: Niklas Cassel <cassel@kernel.org> > Closes: https://lore.kernel.org/linux-pci/ZWYmX8Y%2F7Q9WMxES@x1-carbon > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Reviewed-by: Frank Li <Frank.Li@nxp.com> > --- > drivers/pci/controller/dwc/pcie-designware-ep.c | 11 +++++++++-- > drivers/pci/controller/dwc/pcie-designware.h | 5 +++++ > drivers/pci/controller/dwc/pcie-qcom-ep.c | 1 + > drivers/pci/controller/dwc/pcie-tegra194.c | 2 ++ > 4 files changed, 17 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c > index 2b11290aab4c..1205bfba8310 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > @@ -564,12 +564,19 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no, > return 0; > } > > -void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) > { > struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > - struct pci_epc *epc = ep->epc; > > dw_pcie_edma_remove(pci); > +} > +EXPORT_SYMBOL_GPL(dw_pcie_ep_cleanup); > + > +void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > +{ > + struct pci_epc *epc = ep->epc; > + > + dw_pcie_ep_cleanup(ep); > > pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem, > epc->mem->window.page_size); > diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h > index 61465203bb60..351d2fe3ea4d 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.h > +++ b/drivers/pci/controller/dwc/pcie-designware.h > @@ -672,6 +672,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep); > int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep); > void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep); > void dw_pcie_ep_deinit(struct dw_pcie_ep *ep); > +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep); > int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no); > int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no, > u8 interrupt_num); > @@ -705,6 +706,10 @@ static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > { > } > > +static inline void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) > +{ > +} > + > static inline int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no) > { > return 0; > diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c > index 36e5e80cd22f..59b1c0110288 100644 > --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c > +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c > @@ -507,6 +507,7 @@ static void qcom_pcie_perst_assert(struct dw_pcie *pci) > return; > } > > + dw_pcie_ep_cleanup(&pci->ep); > qcom_pcie_disable_resources(pcie_ep); > pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED; > } > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c > index 7afa9e9aabe2..68bfeed3429b 100644 > --- a/drivers/pci/controller/dwc/pcie-tegra194.c > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c > @@ -1715,6 +1715,8 @@ static void pex_ep_event_pex_rst_assert(struct tegra_pcie_dw *pcie) > if (ret) > dev_err(pcie->dev, "Failed to go Detect state: %d\n", ret); > > + dw_pcie_ep_cleanup(&pcie->pci.ep); > + > reset_control_assert(pcie->core_rst); > > tegra_pcie_disable_phy(pcie); > > -- > 2.25.1 >
On Sat, Feb 24, 2024 at 12:24:09PM +0530, Manivannan Sadhasivam wrote: > For DWC glue drivers supporting PERST# (currently Qcom and Tegra194), some > of the DWC resources like eDMA should be cleaned up during the PERST# > assert time. > > So let's introduce a dw_pcie_ep_cleanup() API that could be called by these > drivers to cleanup the DWC specific resources. Currently, it just removes > eDMA. > > Reported-by: Niklas Cassel <cassel@kernel.org> > Closes: https://lore.kernel.org/linux-pci/ZWYmX8Y%2F7Q9WMxES@x1-carbon > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > --- > drivers/pci/controller/dwc/pcie-designware-ep.c | 11 +++++++++-- > drivers/pci/controller/dwc/pcie-designware.h | 5 +++++ > drivers/pci/controller/dwc/pcie-qcom-ep.c | 1 + > drivers/pci/controller/dwc/pcie-tegra194.c | 2 ++ > 4 files changed, 17 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c > index 2b11290aab4c..1205bfba8310 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > @@ -564,12 +564,19 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no, > return 0; > } > > -void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) > { > struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > - struct pci_epc *epc = ep->epc; > > dw_pcie_edma_remove(pci); Hello Mani, In this message: https://lore.kernel.org/linux-pci/20240130062938.GB32821@thinkpad/ You mentioned that you were going to clean up the BARs. (Like I wrote in that thread, I really think that we should merge a fix for the broken "do we have a saved value from find_first_zero_bit() in the array", by using a "if (!saved_value[bar])", when find_first_zero_bit() returns zero.) However, regardless of that, I do not see that this series (neither dw_pcie_ep_cleanup(), nor dw_pcie_ep_linkdown()), calls any function which will clean up the BARs. Since e.g. qcom-ep.c does a reset_control_assert() during perst assert/deassert, which should clear sticky registers, I think that you should let dw_pcie_ep_cleanup() clean up the BARs using dw_pcie_ep_clear_bar(). Kind regards, Niklas > +} > +EXPORT_SYMBOL_GPL(dw_pcie_ep_cleanup); > + > +void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > +{ > + struct pci_epc *epc = ep->epc; > + > + dw_pcie_ep_cleanup(ep); > > pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem, > epc->mem->window.page_size); > diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h > index 61465203bb60..351d2fe3ea4d 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.h > +++ b/drivers/pci/controller/dwc/pcie-designware.h > @@ -672,6 +672,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep); > int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep); > void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep); > void dw_pcie_ep_deinit(struct dw_pcie_ep *ep); > +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep); > int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no); > int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no, > u8 interrupt_num); > @@ -705,6 +706,10 @@ static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > { > } > > +static inline void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) > +{ > +} > + > static inline int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no) > { > return 0; > diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c > index 36e5e80cd22f..59b1c0110288 100644 > --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c > +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c > @@ -507,6 +507,7 @@ static void qcom_pcie_perst_assert(struct dw_pcie *pci) > return; > } > > + dw_pcie_ep_cleanup(&pci->ep); > qcom_pcie_disable_resources(pcie_ep); > pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED; > } > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c > index 7afa9e9aabe2..68bfeed3429b 100644 > --- a/drivers/pci/controller/dwc/pcie-tegra194.c > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c > @@ -1715,6 +1715,8 @@ static void pex_ep_event_pex_rst_assert(struct tegra_pcie_dw *pcie) > if (ret) > dev_err(pcie->dev, "Failed to go Detect state: %d\n", ret); > > + dw_pcie_ep_cleanup(&pcie->pci.ep); > + > reset_control_assert(pcie->core_rst); > > tegra_pcie_disable_phy(pcie); > > -- > 2.25.1 >
On Thu, Feb 29, 2024 at 01:40:29PM +0100, Niklas Cassel wrote: > On Sat, Feb 24, 2024 at 12:24:09PM +0530, Manivannan Sadhasivam wrote: > > For DWC glue drivers supporting PERST# (currently Qcom and Tegra194), some > > of the DWC resources like eDMA should be cleaned up during the PERST# > > assert time. > > > > So let's introduce a dw_pcie_ep_cleanup() API that could be called by these > > drivers to cleanup the DWC specific resources. Currently, it just removes > > eDMA. > > > > Reported-by: Niklas Cassel <cassel@kernel.org> > > Closes: https://lore.kernel.org/linux-pci/ZWYmX8Y%2F7Q9WMxES@x1-carbon > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > > --- > > drivers/pci/controller/dwc/pcie-designware-ep.c | 11 +++++++++-- > > drivers/pci/controller/dwc/pcie-designware.h | 5 +++++ > > drivers/pci/controller/dwc/pcie-qcom-ep.c | 1 + > > drivers/pci/controller/dwc/pcie-tegra194.c | 2 ++ > > 4 files changed, 17 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c > > index 2b11290aab4c..1205bfba8310 100644 > > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c > > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > > @@ -564,12 +564,19 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no, > > return 0; > > } > > > > -void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) > > +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) > > { > > struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > > - struct pci_epc *epc = ep->epc; > > > > dw_pcie_edma_remove(pci); > > Hello Mani, > > In this message: > https://lore.kernel.org/linux-pci/20240130062938.GB32821@thinkpad/ > > You mentioned that you were going to clean up the BARs. Yes, I did and it is still in my queue. > (Like I wrote in that thread, I really think that we should merge a fix for > the broken "do we have a saved value from find_first_zero_bit() in the array", > by using a "if (!saved_value[bar])", when find_first_zero_bit() returns zero.) > Hmm, yeah that logic is flawed. Let me take another look. > However, regardless of that, I do not see that this series (neither > dw_pcie_ep_cleanup(), nor dw_pcie_ep_linkdown()), calls any function which > will clean up the BARs. > > Since e.g. qcom-ep.c does a reset_control_assert() during perst > assert/deassert, which should clear sticky registers, I think that > you should let dw_pcie_ep_cleanup() clean up the BARs using > dw_pcie_ep_clear_bar(). > As I mentioned earlier, it is the job of the EPF drivers to clear the BARs since they allocate them. I'm trying to reduce the implicit resetting wherever we could. The proper fix is to add the LINK_DOWN callback to EPF drivers and do cleanup. I'm planning to submit a series for that after this one. - Mani
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 2b11290aab4c..1205bfba8310 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -564,12 +564,19 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no, return 0; } -void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) { struct dw_pcie *pci = to_dw_pcie_from_ep(ep); - struct pci_epc *epc = ep->epc; dw_pcie_edma_remove(pci); +} +EXPORT_SYMBOL_GPL(dw_pcie_ep_cleanup); + +void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) +{ + struct pci_epc *epc = ep->epc; + + dw_pcie_ep_cleanup(ep); pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem, epc->mem->window.page_size); diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 61465203bb60..351d2fe3ea4d 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -672,6 +672,7 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep); int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep); void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep); void dw_pcie_ep_deinit(struct dw_pcie_ep *ep); +void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep); int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no); int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no, u8 interrupt_num); @@ -705,6 +706,10 @@ static inline void dw_pcie_ep_deinit(struct dw_pcie_ep *ep) { } +static inline void dw_pcie_ep_cleanup(struct dw_pcie_ep *ep) +{ +} + static inline int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no) { return 0; diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c index 36e5e80cd22f..59b1c0110288 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c @@ -507,6 +507,7 @@ static void qcom_pcie_perst_assert(struct dw_pcie *pci) return; } + dw_pcie_ep_cleanup(&pci->ep); qcom_pcie_disable_resources(pcie_ep); pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED; } diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c index 7afa9e9aabe2..68bfeed3429b 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -1715,6 +1715,8 @@ static void pex_ep_event_pex_rst_assert(struct tegra_pcie_dw *pcie) if (ret) dev_err(pcie->dev, "Failed to go Detect state: %d\n", ret); + dw_pcie_ep_cleanup(&pcie->pci.ep); + reset_control_assert(pcie->core_rst); tegra_pcie_disable_phy(pcie);
For DWC glue drivers supporting PERST# (currently Qcom and Tegra194), some of the DWC resources like eDMA should be cleaned up during the PERST# assert time. So let's introduce a dw_pcie_ep_cleanup() API that could be called by these drivers to cleanup the DWC specific resources. Currently, it just removes eDMA. Reported-by: Niklas Cassel <cassel@kernel.org> Closes: https://lore.kernel.org/linux-pci/ZWYmX8Y%2F7Q9WMxES@x1-carbon Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> --- drivers/pci/controller/dwc/pcie-designware-ep.c | 11 +++++++++-- drivers/pci/controller/dwc/pcie-designware.h | 5 +++++ drivers/pci/controller/dwc/pcie-qcom-ep.c | 1 + drivers/pci/controller/dwc/pcie-tegra194.c | 2 ++ 4 files changed, 17 insertions(+), 2 deletions(-)