[PATCH v3] PCI: xilinx-nwl: Remove unnecessary code which updates primary, secondary and sub-ordinate bus numbers

[PATCH v3] PCI: xilinx-nwl: Remove unnecessary code which updates primary, secondary and sub-ordinate bus numbers

[Thippeswamy Havalige]

The primary,secondary and sub-ordinate bus number registers are updated by
Linux PCI core, so remove code which updates respective fields of type 1
header.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@amd.com>
---
changes in v4:
- None
changes in v3:
- Remove unnecessary period at end of subject line.
- Updated commit message.
changes in v2:
- Code increasing ECAM Size value is added into a seperate patch.
- Modified commit messages.
changes in v1:
- Modified commit messages.
---
 drivers/pci/controller/pcie-xilinx-nwl.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
index 176686bdb15c..d8a3a08be1d5 100644
--- a/drivers/pci/controller/pcie-xilinx-nwl.c
+++ b/drivers/pci/controller/pcie-xilinx-nwl.c
@@ -166,7 +166,6 @@ struct nwl_pcie {
 	int irq_intx;
 	int irq_misc;
 	u32 ecam_value;
-	u8 last_busno;
 	struct nwl_msi msi;
 	struct irq_domain *legacy_irq_domain;
 	struct clk *clk;
@@ -625,7 +624,7 @@ static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
 {
 	struct device *dev = pcie->dev;
 	struct platform_device *pdev = to_platform_device(dev);
-	u32 breg_val, ecam_val, first_busno = 0;
+	u32 breg_val, ecam_val;
 	int err;
 
 	breg_val = nwl_bridge_readl(pcie, E_BREG_CAPABILITIES) & BREG_PRESENT;
@@ -683,15 +682,6 @@ static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
 	nwl_bridge_writel(pcie, upper_32_bits(pcie->phys_ecam_base),
 			  E_ECAM_BASE_HI);
 
-	/* Get bus range */
-	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CONTROL);
-	pcie->last_busno = (ecam_val & E_ECAM_SIZE_LOC) >> E_ECAM_SIZE_SHIFT;
-	/* Write primary, secondary and subordinate bus numbers */
-	ecam_val = first_busno;
-	ecam_val |= (first_busno + 1) << 8;
-	ecam_val |= (pcie->last_busno << E_ECAM_SIZE_SHIFT);
-	writel(ecam_val, (pcie->ecam_base + PCI_PRIMARY_BUS));
-
 	if (nwl_pcie_link_up(pcie))
 		dev_info(dev, "Link is UP\n");
 	else
-- 
2.17.1

[PATCH v4 0/3] Fix ecam size value to discover 256 buses during

[Thippeswamy Havalige]

Current driver is supports up to 16 buses. The following code fixes 
to support up to 256 buses.

update "NWL_ECAM_VALUE_DEFAULT " to 16  can access up to 256MB ECAM
region to detect 256 buses.

Update ecam size to 256MB in device tree binding example.


 Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml | 2 +-
 drivers/pci/controller/pcie-xilinx-nwl.c                 | 6 ++----
 2 files changed, 3 insertions(+), 5 deletions(-)

-- 
2.17.1

[PATCH v4 1/3] dt-bindings: PCI: xilinx-nwl: Modify ECAM size in example

[Thippeswamy Havalige]

Update ECAM size in example to discover up to 256 buses.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@amd.com>
Acked-by: Rob Herring <robh@kernel.org>
---
changes in v4:
None
changes in v3:
None
changes in v2:
None.
changes in v1:
None.
---
 Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml b/Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml
index 897602559b37..426f90a47f35 100644
--- a/Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/xlnx,nwl-pcie.yaml
@@ -118,7 +118,7 @@ examples:
             compatible = "xlnx,nwl-pcie-2.11";
             reg = <0x0 0xfd0e0000 0x0 0x1000>,
                   <0x0 0xfd480000 0x0 0x1000>,
-                  <0x80 0x00000000 0x0 0x1000000>;
+                  <0x80 0x00000000 0x0 0x10000000>;
             reg-names = "breg", "pcireg", "cfg";
             ranges = <0x02000000 0x0 0xe0000000 0x0 0xe0000000 0x0 0x10000000>,
                      <0x43000000 0x00000006 0x0 0x00000006 0x0 0x00000002 0x0>;
-- 
2.17.1

[PATCH v4 2/3] PCI: xilinx-nwl: Rename ECAM size default macro.

[Thippeswamy Havalige]

Rename "NWL_ECAM_VALUE_DEFAULT" to a suitable macro name and remove
redundant code.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@amd.com>
---
changes in v4:
- Rename macro
changes in v3:
- Remove periods at end of subject line
- Update commit logs
changes in v2:
- Update this changes in a seperate patch.
---
 drivers/pci/controller/pcie-xilinx-nwl.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
index d8a3a08be1d5..8fe0e8a325b0 100644
--- a/drivers/pci/controller/pcie-xilinx-nwl.c
+++ b/drivers/pci/controller/pcie-xilinx-nwl.c
@@ -126,7 +126,7 @@
 #define E_ECAM_CR_ENABLE		BIT(0)
 #define E_ECAM_SIZE_LOC			GENMASK(20, 16)
 #define E_ECAM_SIZE_SHIFT		16
-#define NWL_ECAM_VALUE_DEFAULT		12
+#define NWL_ECAM_MAX_SIZE		12
 
 #define CFG_DMA_REG_BAR			GENMASK(2, 0)
 #define CFG_PCIE_CACHE			GENMASK(7, 0)
@@ -165,7 +165,6 @@ struct nwl_pcie {
 	u32 ecam_size;
 	int irq_intx;
 	int irq_misc;
-	u32 ecam_value;
 	struct nwl_msi msi;
 	struct irq_domain *legacy_irq_domain;
 	struct clk *clk;
@@ -674,7 +673,7 @@ static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
 			  E_ECAM_CR_ENABLE, E_ECAM_CONTROL);
 
 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
-			  (pcie->ecam_value << E_ECAM_SIZE_SHIFT),
+			  (NWL_ECAM_MAX_SIZE << E_ECAM_SIZE_SHIFT),
 			  E_ECAM_CONTROL);
 
 	nwl_bridge_writel(pcie, lower_32_bits(pcie->phys_ecam_base),
@@ -782,7 +781,6 @@ static int nwl_pcie_probe(struct platform_device *pdev)
 	pcie = pci_host_bridge_priv(bridge);
 
 	pcie->dev = dev;
-	pcie->ecam_value = NWL_ECAM_VALUE_DEFAULT;
 
 	err = nwl_pcie_parse_dt(pcie, pdev);
 	if (err) {
-- 
2.17.1

[PATCH v4 3/3] PCI: xilinx-nwl: Increase ECAM size to accommodate 256 buses

[Thippeswamy Havalige]

Our controller is expecting ECAM size to be programmed by software. By
programming "NWL_ECAM_VALUE_DEFAULT  12" controller can access up to 16MB
ECAM region which is used to detect 16 buses, so by updating
"NWL_ECAM_VALUE_DEFAULT" to 16 so that controller can access up to 256MB
ECAM region to detect 256 buses.

Nothing will break, when having a DT with the smaller ECAM size and boot a
kernel that includes this change,but the kernel will only be able to use 16
buses.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
---
Changes in v4:
Move modified ECAM max size macro into a seperate patch.
 drivers/pci/controller/pcie-xilinx-nwl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
index 8fe0e8a325b0..e307aceba5c9 100644
--- a/drivers/pci/controller/pcie-xilinx-nwl.c
+++ b/drivers/pci/controller/pcie-xilinx-nwl.c
@@ -126,7 +126,7 @@
 #define E_ECAM_CR_ENABLE		BIT(0)
 #define E_ECAM_SIZE_LOC			GENMASK(20, 16)
 #define E_ECAM_SIZE_SHIFT		16
-#define NWL_ECAM_MAX_SIZE		12
+#define NWL_ECAM_MAX_SIZE		16
 
 #define CFG_DMA_REG_BAR			GENMASK(2, 0)
 #define CFG_PCIE_CACHE			GENMASK(7, 0)
-- 
2.17.1