[PATCH] pci/layerscape: fix MSG TLP drop setting

[PATCH] pci/layerscape: fix MSG TLP drop setting

[Minghuan Lian]

Some kinds of Layerscape PCIe controllers will forward the received
message TLPs to system application address space, which could corrupt
system memory or lead to a system hang. The patch enables the MSG_DROP
to fix this issue.

Signed-off-by: Minghuan Lian <Minghuan.Lian@nxp.com>
---
 drivers/pci/host/pci-layerscape.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
index 3923bed..f39961b 100644
--- a/drivers/pci/host/pci-layerscape.c
+++ b/drivers/pci/host/pci-layerscape.c
@@ -77,6 +77,16 @@ static void ls_pcie_fix_class(struct ls_pcie *pcie)
 	iowrite16(PCI_CLASS_BRIDGE_PCI, pcie->dbi + PCI_CLASS_DEVICE);
 }
 
+/* Drop MSG TLP except for Vendor MSG */
+static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
+{
+	u32 val;
+
+	val = ioread32(pcie->dbi + PCIE_STRFMR1);
+	val &= 0xDFFFFFFF;
+	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
+}
+
 static int ls1021_pcie_link_up(struct pcie_port *pp)
 {
 	u32 state;
@@ -97,7 +107,7 @@ static int ls1021_pcie_link_up(struct pcie_port *pp)
 static void ls1021_pcie_host_init(struct pcie_port *pp)
 {
 	struct ls_pcie *pcie = to_ls_pcie(pp);
-	u32 val, index[2];
+	u32 index[2];
 
 	pcie->scfg = syscon_regmap_lookup_by_phandle(pp->dev->of_node,
 						     "fsl,pcie-scfg");
@@ -116,13 +126,7 @@ static void ls1021_pcie_host_init(struct pcie_port *pp)
 
 	dw_pcie_setup_rc(pp);
 
-	/*
-	 * LS1021A Workaround for internal TKT228622
-	 * to fix the INTx hang issue
-	 */
-	val = ioread32(pcie->dbi + PCIE_STRFMR1);
-	val &= 0xffff;
-	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
+	ls_pcie_drop_msg_tlp(pcie);
 }
 
 static int ls_pcie_link_up(struct pcie_port *pp)
@@ -147,6 +151,7 @@ static void ls_pcie_host_init(struct pcie_port *pp)
 	iowrite32(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
 	ls_pcie_fix_class(pcie);
 	ls_pcie_clear_multifunction(pcie);
+	ls_pcie_drop_msg_tlp(pcie);
 	iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
 }
 
-- 
1.9.1

Re: [PATCH] pci/layerscape: fix MSG TLP drop setting

[Bjorn Helgaas]

On Thu, Feb 25, 2016 at 03:04:30PM +0800, Minghuan Lian wrote:
> Some kinds of Layerscape PCIe controllers will forward the received
> message TLPs to system application address space, which could corrupt
> system memory or lead to a system hang. The patch enables the MSG_DROP
> to fix this issue.
> 
> Signed-off-by: Minghuan Lian <Minghuan.Lian@nxp.com>

Applied to for-linus for v4.5, thanks, Minghuan!

> ---
>  drivers/pci/host/pci-layerscape.c | 21 +++++++++++++--------
>  1 file changed, 13 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
> index 3923bed..f39961b 100644
> --- a/drivers/pci/host/pci-layerscape.c
> +++ b/drivers/pci/host/pci-layerscape.c
> @@ -77,6 +77,16 @@ static void ls_pcie_fix_class(struct ls_pcie *pcie)
>  	iowrite16(PCI_CLASS_BRIDGE_PCI, pcie->dbi + PCI_CLASS_DEVICE);
>  }
>  
> +/* Drop MSG TLP except for Vendor MSG */
> +static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
> +{
> +	u32 val;
> +
> +	val = ioread32(pcie->dbi + PCIE_STRFMR1);
> +	val &= 0xDFFFFFFF;
> +	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
> +}
> +
>  static int ls1021_pcie_link_up(struct pcie_port *pp)
>  {
>  	u32 state;
> @@ -97,7 +107,7 @@ static int ls1021_pcie_link_up(struct pcie_port *pp)
>  static void ls1021_pcie_host_init(struct pcie_port *pp)
>  {
>  	struct ls_pcie *pcie = to_ls_pcie(pp);
> -	u32 val, index[2];
> +	u32 index[2];
>  
>  	pcie->scfg = syscon_regmap_lookup_by_phandle(pp->dev->of_node,
>  						     "fsl,pcie-scfg");
> @@ -116,13 +126,7 @@ static void ls1021_pcie_host_init(struct pcie_port *pp)
>  
>  	dw_pcie_setup_rc(pp);
>  
> -	/*
> -	 * LS1021A Workaround for internal TKT228622
> -	 * to fix the INTx hang issue
> -	 */
> -	val = ioread32(pcie->dbi + PCIE_STRFMR1);
> -	val &= 0xffff;
> -	iowrite32(val, pcie->dbi + PCIE_STRFMR1);
> +	ls_pcie_drop_msg_tlp(pcie);
>  }
>  
>  static int ls_pcie_link_up(struct pcie_port *pp)
> @@ -147,6 +151,7 @@ static void ls_pcie_host_init(struct pcie_port *pp)
>  	iowrite32(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
>  	ls_pcie_fix_class(pcie);
>  	ls_pcie_clear_multifunction(pcie);
> +	ls_pcie_drop_msg_tlp(pcie);
>  	iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
>  }
>  
> -- 
> 1.9.1
> 
> --
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