[v4,3/5] PCI: designware-ep: Make dw_pcie_ep_reset_bar() handle 64-bit BARs properly

Message ID 20180308133331.19464-4-niklas.cassel@axis.com
State Superseded
Delegated to: Lorenzo Pieralisi
Headers show
Series
  • PCI endpoint 64-bit BAR fixes
Related show

Commit Message

Niklas Cassel March 8, 2018, 1:33 p.m.
Since a 64-bit BAR consists of a BAR pair, we need to write to both
BARs in the BAR pair to clear the BAR properly.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
---
 drivers/pci/dwc/pcie-designware-ep.c | 7 +++++++
 1 file changed, 7 insertions(+)

Comments

Kishon Vijay Abraham I March 21, 2018, 5:54 a.m. | #1
Hi Niklas,

On Thursday 08 March 2018 07:03 PM, Niklas Cassel wrote:
> Since a 64-bit BAR consists of a BAR pair, we need to write to both
> BARs in the BAR pair to clear the BAR properly.
> 
> Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
> ---
>  drivers/pci/dwc/pcie-designware-ep.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
> index 946bbdf53c4d..b20b2651caf9 100644
> --- a/drivers/pci/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/dwc/pcie-designware-ep.c
> @@ -22,11 +22,18 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
>  void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
>  {
>  	u32 reg;
> +	u32 val;
>  
>  	reg = PCI_BASE_ADDRESS_0 + (4 * bar);
> +	val = dw_pcie_readl_dbi(pci, reg);
>  	dw_pcie_dbi_ro_wr_en(pci);
>  	dw_pcie_writel_dbi2(pci, reg, 0x0);
>  	dw_pcie_writel_dbi(pci, reg, 0x0);
> +	if (!(val & PCI_BASE_ADDRESS_SPACE_IO) &&
> +	    (val & PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> +		dw_pcie_writel_dbi2(pci, reg + 4, 0x0);
> +		dw_pcie_writel_dbi(pci, reg + 4, 0x0);
> +	}

same comment as previous patch apply here too.

Thanks
Kishon

Patch

diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
index 946bbdf53c4d..b20b2651caf9 100644
--- a/drivers/pci/dwc/pcie-designware-ep.c
+++ b/drivers/pci/dwc/pcie-designware-ep.c
@@ -22,11 +22,18 @@  void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
 {
 	u32 reg;
+	u32 val;
 
 	reg = PCI_BASE_ADDRESS_0 + (4 * bar);
+	val = dw_pcie_readl_dbi(pci, reg);
 	dw_pcie_dbi_ro_wr_en(pci);
 	dw_pcie_writel_dbi2(pci, reg, 0x0);
 	dw_pcie_writel_dbi(pci, reg, 0x0);
+	if (!(val & PCI_BASE_ADDRESS_SPACE_IO) &&
+	    (val & PCI_BASE_ADDRESS_MEM_TYPE_64)) {
+		dw_pcie_writel_dbi2(pci, reg + 4, 0x0);
+		dw_pcie_writel_dbi(pci, reg + 4, 0x0);
+	}
 	dw_pcie_dbi_ro_wr_dis(pci);
 }