[PATCH v3 0/2] brcmstb: initial work on BCM4908

[PATCH v3 0/2] brcmstb: initial work on BCM4908

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

BCM4908 uses very similar hardware to the STB one. It still requires
some tweaks but this initial work allows accessing hardware without:

Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP

Rafał Miłecki (2):
  dt-bindings: PCI: brcmstb: add BCM4908 binding
  PCI: brcmstb: support BCM4908 with external PERST# signal controller

 .../bindings/pci/brcm,stb-pcie.yaml           | 37 ++++++++++++++-----
 drivers/pci/controller/Kconfig                |  2 +-
 drivers/pci/controller/pcie-brcmstb.c         | 32 ++++++++++++++++
 3 files changed, 61 insertions(+), 10 deletions(-)

-- 
2.26.2

[PATCH v3 1/2] dt-bindings: PCI: brcmstb: add BCM4908 binding

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

BCM4908 is a SoC family with PCIe controller sharing design with the one
for STB. BCM4908 has different power management and memory controller so
few tweaks are required.

PERST# signal on BCM4908 is handled by an external MISC block so it
needs specifying a reset phandle.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
---
V3: Drop "reset-names" from the generic "properties" - it's now defined as
    "compatible" specific property
    Drop "$ref" from the "resets" - thanks Rob.
---
 .../bindings/pci/brcm,stb-pcie.yaml           | 37 ++++++++++++++-----
 1 file changed, 28 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml b/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml
index 807694b4f41f..f90557f6deb8 100644
--- a/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/brcm,stb-pcie.yaml
@@ -14,6 +14,7 @@ properties:
     items:
       - enum:
           - brcm,bcm2711-pcie # The Raspberry Pi 4
+          - brcm,bcm4908-pcie
           - brcm,bcm7211-pcie # Broadcom STB version of RPi4
           - brcm,bcm7278-pcie # Broadcom 7278 Arm
           - brcm,bcm7216-pcie # Broadcom 7216 Arm
@@ -63,15 +64,6 @@ properties:
 
   aspm-no-l0s: true
 
-  resets:
-    description: for "brcm,bcm7216-pcie", must be a valid reset
-      phandle pointing to the RESCAL reset controller provider node.
-    $ref: "/schemas/types.yaml#/definitions/phandle"
-
-  reset-names:
-    items:
-      - const: rescal
-
   brcm,scb-sizes:
     description: u64 giving the 64bit PCIe memory
       viewport size of a memory controller.  There may be up to
@@ -98,12 +90,39 @@ required:
 
 allOf:
   - $ref: /schemas/pci/pci-bus.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: brcm,bcm4908-pcie
+    then:
+      properties:
+        resets:
+          items:
+            - description: reset controller handling the PERST# signal
+
+        reset-names:
+          items:
+            - const: perst
+
+      required:
+        - resets
+        - reset-names
   - if:
       properties:
         compatible:
           contains:
             const: brcm,bcm7216-pcie
     then:
+      properties:
+        resets:
+          items:
+            - description: phandle pointing to the RESCAL reset controller
+
+        reset-names:
+          items:
+            - const: rescal
+
       required:
         - resets
         - reset-names
-- 
2.26.2

Re: [PATCH v3 1/2] dt-bindings: PCI: brcmstb: add BCM4908 binding

[Rob Herring]

On Thu, 10 Dec 2020 19:04:20 +0100, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
> 
> BCM4908 is a SoC family with PCIe controller sharing design with the one
> for STB. BCM4908 has different power management and memory controller so
> few tweaks are required.
> 
> PERST# signal on BCM4908 is handled by an external MISC block so it
> needs specifying a reset phandle.
> 
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> Acked-by: Florian Fainelli <f.fainelli@gmail.com>
> ---
> V3: Drop "reset-names" from the generic "properties" - it's now defined as
>     "compatible" specific property
>     Drop "$ref" from the "resets" - thanks Rob.
> ---
>  .../bindings/pci/brcm,stb-pcie.yaml           | 37 ++++++++++++++-----
>  1 file changed, 28 insertions(+), 9 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

[PATCH v3 2/2] PCI: brcmstb: support BCM4908 with external PERST# signal controller

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

BCM4908 uses external MISC block for controlling PERST# signal. Use it
as a reset controller.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
---
V2: Reorder BCM4908 in the enum pcie_type
    Use devm_reset_control_get_optional_exclusive()
    Don't move hw_rev read up in the code
---
 drivers/pci/controller/Kconfig        |  2 +-
 drivers/pci/controller/pcie-brcmstb.c | 32 +++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 64e2f5e379aa..d44c70bb88f6 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -273,7 +273,7 @@ config VMD
 
 config PCIE_BRCMSTB
 	tristate "Broadcom Brcmstb PCIe host controller"
-	depends on ARCH_BRCMSTB || ARCH_BCM2835 || COMPILE_TEST
+	depends on ARCH_BRCMSTB || ARCH_BCM2835 || ARCH_BCM4908 || COMPILE_TEST
 	depends on OF
 	depends on PCI_MSI_IRQ_DOMAIN
 	default ARCH_BRCMSTB
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 9c3d2982248d..98536cf3af58 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -96,6 +96,7 @@
 
 #define PCIE_MISC_REVISION				0x406c
 #define  BRCM_PCIE_HW_REV_33				0x0303
+#define  BRCM_PCIE_HW_REV_3_20				0x0320
 
 #define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT		0x4070
 #define  PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK	0xfff00000
@@ -190,6 +191,7 @@
 struct brcm_pcie;
 static inline void brcm_pcie_bridge_sw_init_set_7278(struct brcm_pcie *pcie, u32 val);
 static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie, u32 val);
+static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val);
 static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val);
 static inline void brcm_pcie_perst_set_generic(struct brcm_pcie *pcie, u32 val);
 
@@ -206,6 +208,7 @@ enum {
 
 enum pcie_type {
 	GENERIC,
+	BCM4908,
 	BCM7278,
 	BCM2711,
 };
@@ -230,6 +233,13 @@ static const struct pcie_cfg_data generic_cfg = {
 	.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
 };
 
+static const struct pcie_cfg_data bcm4908_cfg = {
+	.offsets	= pcie_offsets,
+	.type		= BCM4908,
+	.perst_set	= brcm_pcie_perst_set_4908,
+	.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
+};
+
 static const int pcie_offset_bcm7278[] = {
 	[RGR1_SW_INIT_1] = 0xc010,
 	[EXT_CFG_INDEX] = 0x9000,
@@ -282,6 +292,7 @@ struct brcm_pcie {
 	const int		*reg_offsets;
 	enum pcie_type		type;
 	struct reset_control	*rescal;
+	struct reset_control	*perst_reset;
 	int			num_memc;
 	u64			memc_size[PCIE_BRCM_MAX_MEMC];
 	u32			hw_rev;
@@ -747,6 +758,17 @@ static inline void brcm_pcie_bridge_sw_init_set_7278(struct brcm_pcie *pcie, u32
 	writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
 }
 
+static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val)
+{
+	if (WARN_ONCE(!pcie->perst_reset, "missing PERST# reset controller\n"))
+		return;
+
+	if (val)
+		reset_control_assert(pcie->perst_reset);
+	else
+		reset_control_deassert(pcie->perst_reset);
+}
+
 static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val)
 {
 	u32 tmp;
@@ -1206,6 +1228,7 @@ static int brcm_pcie_remove(struct platform_device *pdev)
 
 static const struct of_device_id brcm_pcie_match[] = {
 	{ .compatible = "brcm,bcm2711-pcie", .data = &bcm2711_cfg },
+	{ .compatible = "brcm,bcm4908-pcie", .data = &bcm4908_cfg },
 	{ .compatible = "brcm,bcm7211-pcie", .data = &generic_cfg },
 	{ .compatible = "brcm,bcm7278-pcie", .data = &bcm7278_cfg },
 	{ .compatible = "brcm,bcm7216-pcie", .data = &bcm7278_cfg },
@@ -1262,6 +1285,11 @@ static int brcm_pcie_probe(struct platform_device *pdev)
 		clk_disable_unprepare(pcie->clk);
 		return PTR_ERR(pcie->rescal);
 	}
+	pcie->perst_reset = devm_reset_control_get_optional_exclusive(&pdev->dev, "perst");
+	if (IS_ERR(pcie->perst_reset)) {
+		clk_disable_unprepare(pcie->clk);
+		return PTR_ERR(pcie->perst_reset);
+	}
 
 	ret = reset_control_deassert(pcie->rescal);
 	if (ret)
@@ -1279,6 +1307,10 @@ static int brcm_pcie_probe(struct platform_device *pdev)
 		goto fail;
 
 	pcie->hw_rev = readl(pcie->base + PCIE_MISC_REVISION);
+	if (pcie->type == BCM4908 && pcie->hw_rev >= BRCM_PCIE_HW_REV_3_20) {
+		dev_err(pcie->dev, "hardware revision with unsupported PERST# setup\n");
+		goto fail;
+	}
 
 	msi_np = of_parse_phandle(pcie->np, "msi-parent", 0);
 	if (pci_msi_enabled() && msi_np == pcie->np) {
-- 
2.26.2

Re: [PATCH v3 0/2] brcmstb: initial work on BCM4908

[Lorenzo Pieralisi]

On Thu, 10 Dec 2020 19:04:19 +0100, Rafał Miłecki wrote:
> BCM4908 uses very similar hardware to the STB one. It still requires
> some tweaks but this initial work allows accessing hardware without:
> 
> Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
> 
> Rafał Miłecki (2):
>   dt-bindings: PCI: brcmstb: add BCM4908 binding
>   PCI: brcmstb: support BCM4908 with external PERST# signal controller
> 
> [...]

Applied to pci/brcmstb, thanks!

[1/2] dt-bindings: PCI: brcmstb: add BCM4908 binding
      https://git.kernel.org/lpieralisi/pci/c/f435ce7ebf
[2/2] PCI: brcmstb: support BCM4908 with external PERST# signal controller
      https://git.kernel.org/lpieralisi/pci/c/0cdfaceb98

Thanks,
Lorenzo