[PATCH v3 0/6] Add SiFive FU740 PCIe host controller driver support

[PATCH v3 0/6] Add SiFive FU740 PCIe host controller driver support

[Greentime Hu]

This patchset includes SiFive FU740 PCIe host controller driver. We also
add pcie_aux clock and pcie_power_on_reset controller to prci driver for
PCIe driver to use it.

This is tested with e1000e: Intel(R) PRO/1000 Network Card, AMD Radeon R5
230 graphics card and SP M.2 PCIe Gen 3 SSD in SiFive Unmatched based on
v5.11 Linux kernel.

Changes in v3:
 - Remove items that has been defined
 - Refine format of sifive,fu740-pcie.yaml
 - Replace perstn-gpios with the common one
 - Change DBI mapping space to 2GB from 4GB
 - Refine drivers/reset/Kconfig

Changes in v2:
 - Refine codes based on reviewers' feedback
 - Remove define and use the common one
 - Replace __raw_writel with writel_relaxed
 - Split fu740_phyregreadwrite to write function
 - Use readl_poll_timeout in stead of while loop checking
 - Use dwc common codes
 - Use gpio descriptors and the gpiod_* api.
 - Replace devm_ioremap_resource with devm_platform_ioremap_resource_byname
 - Replace devm_reset_control_get with devm_reset_control_get_exclusive
 - Add more comments for delay and sleep
 - Remove "phy ? x : y" expressions
 - Refine code logic to remove possible infinite loop
 - Replace magic number with meaningful define
 - Remove fu740_pcie_pm_ops
 - Use builtin_platform_driver

Greentime Hu (5):
  clk: sifive: Add pcie_aux clock in prci driver for PCIe driver
  clk: sifive: Use reset-simple in prci driver for PCIe driver
  MAINTAINERS: Add maintainers for SiFive FU740 PCIe driver
  dt-bindings: PCI: Add SiFive FU740 PCIe host controller
  riscv: dts: Add PCIe support for the SiFive FU740-C000 SoC

Paul Walmsley (1):
  PCI: fu740: Add SiFive FU740 PCIe host controller driver

 .../bindings/pci/sifive,fu740-pcie.yaml       | 109 ++++++
 MAINTAINERS                                   |   8 +
 arch/riscv/boot/dts/sifive/fu740-c000.dtsi    |  33 ++
 drivers/clk/sifive/Kconfig                    |   2 +
 drivers/clk/sifive/fu740-prci.c               |  11 +
 drivers/clk/sifive/fu740-prci.h               |   2 +-
 drivers/clk/sifive/sifive-prci.c              |  54 +++
 drivers/clk/sifive/sifive-prci.h              |  13 +
 drivers/pci/controller/dwc/Kconfig            |   9 +
 drivers/pci/controller/dwc/Makefile           |   1 +
 drivers/pci/controller/dwc/pcie-fu740.c       | 324 ++++++++++++++++++
 drivers/reset/Kconfig                         |   1 +
 include/dt-bindings/clock/sifive-fu740-prci.h |   1 +
 13 files changed, 567 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml
 create mode 100644 drivers/pci/controller/dwc/pcie-fu740.c

-- 
2.30.2

[PATCH v3 1/6] clk: sifive: Add pcie_aux clock in prci driver for PCIe driver

[Greentime Hu]

We add pcie_aux clock in this patch so that pcie driver can use
clk_prepare_enable() and clk_disable_unprepare() to enable and disable
pcie_aux clock.

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 drivers/clk/sifive/fu740-prci.c               | 11 +++++
 drivers/clk/sifive/fu740-prci.h               |  2 +-
 drivers/clk/sifive/sifive-prci.c              | 41 +++++++++++++++++++
 drivers/clk/sifive/sifive-prci.h              |  9 ++++
 include/dt-bindings/clock/sifive-fu740-prci.h |  1 +
 5 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sifive/fu740-prci.c b/drivers/clk/sifive/fu740-prci.c
index 764d1097aa51..53f6e00a03b9 100644
--- a/drivers/clk/sifive/fu740-prci.c
+++ b/drivers/clk/sifive/fu740-prci.c
@@ -72,6 +72,12 @@ static const struct clk_ops sifive_fu740_prci_hfpclkplldiv_clk_ops = {
 	.recalc_rate = sifive_prci_hfpclkplldiv_recalc_rate,
 };
 
+static const struct clk_ops sifive_fu740_prci_pcie_aux_clk_ops = {
+	.enable = sifive_prci_pcie_aux_clock_enable,
+	.disable = sifive_prci_pcie_aux_clock_disable,
+	.is_enabled = sifive_prci_pcie_aux_clock_is_enabled,
+};
+
 /* List of clock controls provided by the PRCI */
 struct __prci_clock __prci_init_clocks_fu740[] = {
 	[PRCI_CLK_COREPLL] = {
@@ -120,4 +126,9 @@ struct __prci_clock __prci_init_clocks_fu740[] = {
 		.parent_name = "hfpclkpll",
 		.ops = &sifive_fu740_prci_hfpclkplldiv_clk_ops,
 	},
+	[PRCI_CLK_PCIE_AUX] = {
+		.name = "pcie_aux",
+		.parent_name = "hfclk",
+		.ops = &sifive_fu740_prci_pcie_aux_clk_ops,
+	},
 };
diff --git a/drivers/clk/sifive/fu740-prci.h b/drivers/clk/sifive/fu740-prci.h
index 13ef971f7764..511a0bf7ba2b 100644
--- a/drivers/clk/sifive/fu740-prci.h
+++ b/drivers/clk/sifive/fu740-prci.h
@@ -9,7 +9,7 @@
 
 #include "sifive-prci.h"
 
-#define NUM_CLOCK_FU740	8
+#define NUM_CLOCK_FU740	9
 
 extern struct __prci_clock __prci_init_clocks_fu740[NUM_CLOCK_FU740];
 
diff --git a/drivers/clk/sifive/sifive-prci.c b/drivers/clk/sifive/sifive-prci.c
index c78b042750e2..baf7313dac92 100644
--- a/drivers/clk/sifive/sifive-prci.c
+++ b/drivers/clk/sifive/sifive-prci.c
@@ -448,6 +448,47 @@ void sifive_prci_hfpclkpllsel_use_hfpclkpll(struct __prci_data *pd)
 	r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET);	/* barrier */
 }
 
+/* PCIE AUX clock APIs for enable, disable. */
+int sifive_prci_pcie_aux_clock_is_enabled(struct clk_hw *hw)
+{
+	struct __prci_clock *pc = clk_hw_to_prci_clock(hw);
+	struct __prci_data *pd = pc->pd;
+	u32 r;
+
+	r = __prci_readl(pd, PRCI_PCIE_AUX_OFFSET);
+
+	if (r & PRCI_PCIE_AUX_EN_MASK)
+		return 1;
+	else
+		return 0;
+}
+
+int sifive_prci_pcie_aux_clock_enable(struct clk_hw *hw)
+{
+	struct __prci_clock *pc = clk_hw_to_prci_clock(hw);
+	struct __prci_data *pd = pc->pd;
+	u32 r;
+
+	if (sifive_prci_pcie_aux_clock_is_enabled(hw))
+		return 0;
+
+	__prci_writel(1, PRCI_PCIE_AUX_OFFSET, pd);
+	r = __prci_readl(pd, PRCI_PCIE_AUX_OFFSET);	/* barrier */
+
+	return 0;
+}
+
+void sifive_prci_pcie_aux_clock_disable(struct clk_hw *hw)
+{
+	struct __prci_clock *pc = clk_hw_to_prci_clock(hw);
+	struct __prci_data *pd = pc->pd;
+	u32 r;
+
+	__prci_writel(0, PRCI_PCIE_AUX_OFFSET, pd);
+	r = __prci_readl(pd, PRCI_PCIE_AUX_OFFSET);	/* barrier */
+
+}
+
 /**
  * __prci_register_clocks() - register clock controls in the PRCI
  * @dev: Linux struct device
diff --git a/drivers/clk/sifive/sifive-prci.h b/drivers/clk/sifive/sifive-prci.h
index dbdbd1722688..022c67cf053c 100644
--- a/drivers/clk/sifive/sifive-prci.h
+++ b/drivers/clk/sifive/sifive-prci.h
@@ -67,6 +67,11 @@
 #define PRCI_DDRPLLCFG1_CKE_SHIFT	31
 #define PRCI_DDRPLLCFG1_CKE_MASK	(0x1 << PRCI_DDRPLLCFG1_CKE_SHIFT)
 
+/* PCIEAUX */
+#define PRCI_PCIE_AUX_OFFSET		0x14
+#define PRCI_PCIE_AUX_EN_SHIFT		0
+#define PRCI_PCIE_AUX_EN_MASK		(0x1 << PRCI_PCIE_AUX_EN_SHIFT)
+
 /* GEMGXLPLLCFG0 */
 #define PRCI_GEMGXLPLLCFG0_OFFSET	0x1c
 #define PRCI_GEMGXLPLLCFG0_DIVR_SHIFT	0
@@ -296,4 +301,8 @@ unsigned long sifive_prci_tlclksel_recalc_rate(struct clk_hw *hw,
 unsigned long sifive_prci_hfpclkplldiv_recalc_rate(struct clk_hw *hw,
 						   unsigned long parent_rate);
 
+int sifive_prci_pcie_aux_clock_is_enabled(struct clk_hw *hw);
+int sifive_prci_pcie_aux_clock_enable(struct clk_hw *hw);
+void sifive_prci_pcie_aux_clock_disable(struct clk_hw *hw);
+
 #endif /* __SIFIVE_CLK_SIFIVE_PRCI_H */
diff --git a/include/dt-bindings/clock/sifive-fu740-prci.h b/include/dt-bindings/clock/sifive-fu740-prci.h
index cd7706ea5677..7899b7fee7db 100644
--- a/include/dt-bindings/clock/sifive-fu740-prci.h
+++ b/include/dt-bindings/clock/sifive-fu740-prci.h
@@ -19,5 +19,6 @@
 #define PRCI_CLK_CLTXPLL	       5
 #define PRCI_CLK_TLCLK		       6
 #define PRCI_CLK_PCLK		       7
+#define PRCI_CLK_PCIE_AUX	       8
 
 #endif	/* __DT_BINDINGS_CLOCK_SIFIVE_FU740_PRCI_H */
-- 
2.30.2

[PATCH v3 2/6] clk: sifive: Use reset-simple in prci driver for PCIe driver

[Greentime Hu]

We use reset-simple in this patch so that pcie driver can use
devm_reset_control_get() to get this reset data structure and use
reset_control_deassert() to deassert pcie_power_up_rst_n.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 drivers/clk/sifive/Kconfig       |  2 ++
 drivers/clk/sifive/sifive-prci.c | 13 +++++++++++++
 drivers/clk/sifive/sifive-prci.h |  4 ++++
 drivers/reset/Kconfig            |  1 +
 4 files changed, 20 insertions(+)

diff --git a/drivers/clk/sifive/Kconfig b/drivers/clk/sifive/Kconfig
index 1c14eb20c066..9132c3c4aa86 100644
--- a/drivers/clk/sifive/Kconfig
+++ b/drivers/clk/sifive/Kconfig
@@ -10,6 +10,8 @@ if CLK_SIFIVE
 
 config CLK_SIFIVE_PRCI
 	bool "PRCI driver for SiFive SoCs"
+	select RESET_CONTROLLER
+	select RESET_SIMPLE
 	select CLK_ANALOGBITS_WRPLL_CLN28HPC
 	help
 	  Supports the Power Reset Clock interface (PRCI) IP block found in
diff --git a/drivers/clk/sifive/sifive-prci.c b/drivers/clk/sifive/sifive-prci.c
index baf7313dac92..871ccb287993 100644
--- a/drivers/clk/sifive/sifive-prci.c
+++ b/drivers/clk/sifive/sifive-prci.c
@@ -583,6 +583,19 @@ static int sifive_prci_probe(struct platform_device *pdev)
 	if (IS_ERR(pd->va))
 		return PTR_ERR(pd->va);
 
+	pd->reset.rcdev.owner = THIS_MODULE;
+	pd->reset.rcdev.nr_resets = PRCI_RST_NR;
+	pd->reset.rcdev.ops = &reset_simple_ops;
+	pd->reset.rcdev.of_node = pdev->dev.of_node;
+	pd->reset.active_low = true;
+	pd->reset.membase = pd->va + PRCI_DEVICESRESETREG_OFFSET;
+	spin_lock_init(&pd->reset.lock);
+
+	r = devm_reset_controller_register(&pdev->dev, &pd->reset.rcdev);
+	if (r) {
+		dev_err(dev, "could not register reset controller: %d\n", r);
+		return r;
+	}
 	r = __prci_register_clocks(dev, pd, desc);
 	if (r) {
 		dev_err(dev, "could not register clocks: %d\n", r);
diff --git a/drivers/clk/sifive/sifive-prci.h b/drivers/clk/sifive/sifive-prci.h
index 022c67cf053c..91658a88af4e 100644
--- a/drivers/clk/sifive/sifive-prci.h
+++ b/drivers/clk/sifive/sifive-prci.h
@@ -11,6 +11,7 @@
 
 #include <linux/clk/analogbits-wrpll-cln28hpc.h>
 #include <linux/clk-provider.h>
+#include <linux/reset/reset-simple.h>
 #include <linux/platform_device.h>
 
 /*
@@ -121,6 +122,8 @@
 #define PRCI_DEVICESRESETREG_CHIPLINK_RST_N_MASK			\
 		(0x1 << PRCI_DEVICESRESETREG_CHIPLINK_RST_N_SHIFT)
 
+#define PRCI_RST_NR						7
+
 /* CLKMUXSTATUSREG */
 #define PRCI_CLKMUXSTATUSREG_OFFSET				0x2c
 #define PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_SHIFT		1
@@ -221,6 +224,7 @@
  */
 struct __prci_data {
 	void __iomem *va;
+	struct reset_simple_data reset;
 	struct clk_hw_onecell_data hw_clks;
 };
 
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 71ab75a46491..d0f5d0afc240 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -187,6 +187,7 @@ config RESET_SIMPLE
 	   - RCC reset controller in STM32 MCUs
 	   - Allwinner SoCs
 	   - ZTE's zx2967 family
+	   - SiFive FU740 SoCs
 
 config RESET_STM32MP157
 	bool "STM32MP157 Reset Driver" if COMPILE_TEST
-- 
2.30.2

[PATCH v3 3/6] MAINTAINERS: Add maintainers for SiFive FU740 PCIe driver

[Greentime Hu]

Here add maintainer information for SiFive FU740 PCIe driver.

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index bfc1b86e3e73..4da888be6e80 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13592,6 +13592,14 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
 F:	drivers/pci/controller/dwc/*imx6*
 
+PCI DRIVER FOR FU740
+M:	Paul Walmsley <paul.walmsley@sifive.com>
+M:	Greentime Hu <greentime.hu@sifive.com>
+L:	linux-pci@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml
+F:	drivers/pci/controller/dwc/pcie-fu740.c
+
 PCI DRIVER FOR INTEL VOLUME MANAGEMENT DEVICE (VMD)
 M:	Jonathan Derrick <jonathan.derrick@intel.com>
 L:	linux-pci@vger.kernel.org
-- 
2.30.2

[PATCH v3 4/6] dt-bindings: PCI: Add SiFive FU740 PCIe host controller

[Greentime Hu]

Add PCIe host controller DT bindings of SiFive FU740.

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 .../bindings/pci/sifive,fu740-pcie.yaml       | 109 ++++++++++++++++++
 1 file changed, 109 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml

diff --git a/Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml b/Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml
new file mode 100644
index 000000000000..ccb58e5f06d4
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/sifive,fu740-pcie.yaml
@@ -0,0 +1,109 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/sifive,fu740-pcie.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive FU740 PCIe host controller
+
+description: |+
+  SiFive FU740 PCIe host controller is based on the Synopsys DesignWare
+  PCI core. It shares common features with the PCIe DesignWare core and
+  inherits common properties defined in
+  Documentation/devicetree/bindings/pci/designware-pcie.txt.
+
+maintainers:
+  - Paul Walmsley <paul.walmsley@sifive.com>
+  - Greentime Hu <greentime.hu@sifive.com>
+
+allOf:
+  - $ref: /schemas/pci/pci-bus.yaml#
+
+properties:
+  compatible:
+    const: sifive,fu740-pcie
+
+  reg:
+    maxItems: 3
+
+  reg-names:
+    items:
+      - const: dbi
+      - const: config
+      - const: mgmt
+
+  num-lanes:
+    const: 8
+
+  msi-parent: true
+
+  interrupt-names:
+    items:
+      - const: msi
+      - const: inta
+      - const: intb
+      - const: intc
+      - const: intd
+
+  resets:
+    description: A phandle to the PCIe power up reset line.
+
+  pwren-gpios:
+    description: Should specify the GPIO for controlling the PCI bus device power on.
+    maxItems: 1
+
+required:
+  - dma-coherent
+  - num-lanes
+  - interrupts
+  - interrupt-names
+  - interrupt-parent
+  - interrupt-map-mask
+  - interrupt-map
+  - clock-names
+  - clocks
+  - resets
+  - pwren-gpios
+  - reset-gpios
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    bus {
+        #address-cells = <2>;
+        #size-cells = <2>;
+        #include <dt-bindings/clock/sifive-fu740-prci.h>
+
+        pcie@e00000000 {
+            compatible = "sifive,fu740-pcie";
+            #address-cells = <3>;
+            #size-cells = <2>;
+            #interrupt-cells = <1>;
+            reg = <0xe 0x00000000 0x0 0x80000000>,
+                  <0xd 0xf0000000 0x0 0x10000000>,
+                  <0x0 0x100d0000 0x0 0x1000>;
+            reg-names = "dbi", "config", "mgmt";
+            device_type = "pci";
+            dma-coherent;
+            bus-range = <0x0 0xff>;
+            ranges = <0x81000000  0x0 0x60080000  0x0 0x60080000 0x0 0x10000>,      /* I/O */
+                     <0x82000000  0x0 0x60090000  0x0 0x60090000 0x0 0xff70000>,    /* mem */
+                     <0x82000000  0x0 0x70000000  0x0 0x70000000 0x0 0x1000000>,    /* mem */
+                     <0xc3000000 0x20 0x00000000 0x20 0x00000000 0x20 0x00000000>;  /* mem prefetchable */
+            num-lanes = <0x8>;
+            interrupts = <56>, <57>, <58>, <59>, <60>, <61>, <62>, <63>, <64>;
+            interrupt-names = "msi", "inta", "intb", "intc", "intd";
+            interrupt-parent = <&plic0>;
+            interrupt-map-mask = <0x0 0x0 0x0 0x7>;
+            interrupt-map = <0x0 0x0 0x0 0x1 &plic0 57>,
+                            <0x0 0x0 0x0 0x2 &plic0 58>,
+                            <0x0 0x0 0x0 0x3 &plic0 59>,
+                            <0x0 0x0 0x0 0x4 &plic0 60>;
+            clock-names = "pcie_aux";
+            clocks = <&prci PRCI_CLK_PCIE_AUX>;
+            resets = <&prci 4>;
+            pwren-gpios = <&gpio 5 0>;
+            reset-gpios = <&gpio 8 0>;
+        };
+    };
-- 
2.30.2

[PATCH v3 5/6] PCI: fu740: Add SiFive FU740 PCIe host controller driver

[Greentime Hu]

From: Paul Walmsley <paul.walmsley@sifive.com>

Add driver for the SiFive FU740 PCIe host controller.
This controller is based on the DesignWare PCIe core.

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Co-developed-by: Henry Styles <hes@sifive.com>
Signed-off-by: Henry Styles <hes@sifive.com>
Co-developed-by: Erik Danie <erik.danie@sifive.com>
Signed-off-by: Erik Danie <erik.danie@sifive.com>
Co-developed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 drivers/pci/controller/dwc/Kconfig      |   9 +
 drivers/pci/controller/dwc/Makefile     |   1 +
 drivers/pci/controller/dwc/pcie-fu740.c | 324 ++++++++++++++++++++++++
 3 files changed, 334 insertions(+)
 create mode 100644 drivers/pci/controller/dwc/pcie-fu740.c

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 22c5529e9a65..0a37d21ed64e 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -318,4 +318,13 @@ config PCIE_AL
 	  required only for DT-based platforms. ACPI platforms with the
 	  Annapurna Labs PCIe controller don't need to enable this.
 
+config PCIE_FU740
+	bool "SiFive FU740 PCIe host controller"
+	depends on PCI_MSI_IRQ_DOMAIN
+	depends on SOC_SIFIVE || COMPILE_TEST
+	select PCIE_DW_HOST
+	help
+	  Say Y here if you want PCIe controller support for the SiFive
+	  FU740.
+
 endmenu
diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
index a751553fa0db..625f6aaeb5b8 100644
--- a/drivers/pci/controller/dwc/Makefile
+++ b/drivers/pci/controller/dwc/Makefile
@@ -5,6 +5,7 @@ obj-$(CONFIG_PCIE_DW_EP) += pcie-designware-ep.o
 obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o
 obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
 obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
+obj-$(CONFIG_PCIE_FU740) += pcie-fu740.o
 obj-$(CONFIG_PCI_IMX6) += pci-imx6.o
 obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
 obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone.o
diff --git a/drivers/pci/controller/dwc/pcie-fu740.c b/drivers/pci/controller/dwc/pcie-fu740.c
new file mode 100644
index 000000000000..ebbcbda97490
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-fu740.c
@@ -0,0 +1,324 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FU740 DesignWare PCIe Controller integration
+ * Copyright (C) 2019-2021 SiFive, Inc.
+ * Paul Walmsley
+ * Greentime Hu
+ *
+ * Based in part on the i.MX6 PCIe host controller shim which is:
+ *
+ * Copyright (C) 2013 Kosagi
+ *		https://www.kosagi.com
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/reset.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include "pcie-designware.h"
+
+#define to_fu740_pcie(x)	dev_get_drvdata((x)->dev)
+
+struct fu740_pcie {
+	struct dw_pcie pci;
+	void __iomem *mgmt_base;
+	struct gpio_desc *reset;
+	struct gpio_desc *pwren;
+	struct clk *pcie_aux;
+	struct reset_control *rst;
+};
+
+#define SIFIVE_DEVICESRESETREG		0x28
+
+#define PCIEX8MGMT_PERST_N		0x0
+#define PCIEX8MGMT_APP_LTSSM_ENABLE	0x10
+#define PCIEX8MGMT_APP_HOLD_PHY_RST	0x18
+#define PCIEX8MGMT_DEVICE_TYPE		0x708
+#define PCIEX8MGMT_PHY0_CR_PARA_ADDR	0x860
+#define PCIEX8MGMT_PHY0_CR_PARA_RD_EN	0x870
+#define PCIEX8MGMT_PHY0_CR_PARA_RD_DATA	0x878
+#define PCIEX8MGMT_PHY0_CR_PARA_SEL	0x880
+#define PCIEX8MGMT_PHY0_CR_PARA_WR_DATA	0x888
+#define PCIEX8MGMT_PHY0_CR_PARA_WR_EN	0x890
+#define PCIEX8MGMT_PHY0_CR_PARA_ACK	0x898
+#define PCIEX8MGMT_PHY1_CR_PARA_ADDR	0x8a0
+#define PCIEX8MGMT_PHY1_CR_PARA_RD_EN	0x8b0
+#define PCIEX8MGMT_PHY1_CR_PARA_RD_DATA	0x8b8
+#define PCIEX8MGMT_PHY1_CR_PARA_SEL	0x8c0
+#define PCIEX8MGMT_PHY1_CR_PARA_WR_DATA	0x8c8
+#define PCIEX8MGMT_PHY1_CR_PARA_WR_EN	0x8d0
+#define PCIEX8MGMT_PHY1_CR_PARA_ACK	0x8d8
+
+#define PCIEX8MGMT_PHY_CDR_TRACK_EN	BIT(0)
+#define PCIEX8MGMT_PHY_LOS_THRSHLD	BIT(5)
+#define PCIEX8MGMT_PHY_TERM_EN		BIT(9)
+#define PCIEX8MGMT_PHY_TERM_ACDC	BIT(10)
+#define PCIEX8MGMT_PHY_EN		BIT(11)
+#define PCIEX8MGMT_PHY_INIT_VAL		(PCIEX8MGMT_PHY_CDR_TRACK_EN|\
+					 PCIEX8MGMT_PHY_LOS_THRSHLD|\
+					 PCIEX8MGMT_PHY_TERM_EN|\
+					 PCIEX8MGMT_PHY_TERM_ACDC|\
+					 PCIEX8MGMT_PHY_EN)
+
+#define PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3	0x1008
+#define PCIEX8MGMT_PHY_LANE_OFF		0x100
+#define PCIEX8MGMT_PHY_LANE0_BASE	(PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 0)
+#define PCIEX8MGMT_PHY_LANE1_BASE	(PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 1)
+#define PCIEX8MGMT_PHY_LANE2_BASE	(PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 2)
+#define PCIEX8MGMT_PHY_LANE3_BASE	(PCIEX8MGMT_PHY_LANEN_DIG_ASIC_RX_OVRD_IN_3 + 0x100 * 3)
+
+static void fu740_pcie_assert_reset(struct fu740_pcie *afp)
+{
+	/* Assert PERST_N GPIO */
+	gpiod_set_value_cansleep(afp->reset, 0);
+	/* Assert controller PERST_N */
+	writel_relaxed(0x0, afp->mgmt_base + PCIEX8MGMT_PERST_N);
+}
+
+static void fu740_pcie_deassert_reset(struct fu740_pcie *afp)
+{
+	/* Deassert controller PERST_N */
+	writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PERST_N);
+	/* Deassert PERST_N GPIO */
+	gpiod_set_value_cansleep(afp->reset, 1);
+}
+
+static void fu740_pcie_power_on(struct fu740_pcie *afp)
+{
+	gpiod_set_value_cansleep(afp->pwren, 1);
+	/*
+	 * Ensure that PERST has been asserted for at least 100 ms.
+	 * Section 2.2 of PCI Express Card Electromechanical Specification
+	 * Revision 3.0
+	 */
+	msleep(100);
+}
+
+static void fu740_pcie_drive_reset(struct fu740_pcie *afp)
+{
+	fu740_pcie_assert_reset(afp);
+	fu740_pcie_power_on(afp);
+	fu740_pcie_deassert_reset(afp);
+}
+
+static void fu740_phyregwrite(const uint8_t phy, const uint16_t addr,
+			      const uint16_t wrdata, struct fu740_pcie *afp)
+{
+	struct device *dev = afp->pci.dev;
+	void __iomem *phy_cr_para_addr;
+	void __iomem *phy_cr_para_wr_data;
+	void __iomem *phy_cr_para_wr_en;
+	void __iomem *phy_cr_para_ack;
+	int ret, val;
+
+	/* Setup */
+	if (phy) {
+		phy_cr_para_addr = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_ADDR;
+		phy_cr_para_wr_data = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_WR_DATA;
+		phy_cr_para_wr_en = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_WR_EN;
+		phy_cr_para_ack = afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_ACK;
+	} else {
+		phy_cr_para_addr = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_ADDR;
+		phy_cr_para_wr_data = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_WR_DATA;
+		phy_cr_para_wr_en = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_WR_EN;
+		phy_cr_para_ack = afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_ACK;
+	}
+
+	writel_relaxed(addr, phy_cr_para_addr);
+	writel_relaxed(wrdata, phy_cr_para_wr_data);
+	writel_relaxed(1, phy_cr_para_wr_en);
+
+	/* Wait for wait_idle */
+	ret = readl_poll_timeout(phy_cr_para_ack, val, val, 10, 5000);
+	if (ret)
+		dev_err(dev, "Wait for wait_ilde state failed!\n");
+
+	/* Clear */
+	writel_relaxed(0, phy_cr_para_wr_en);
+
+	/* Wait for ~wait_idle */
+	ret = readl_poll_timeout(phy_cr_para_ack, val, !val, 10, 5000);
+	if (ret)
+		dev_err(dev, "Wait for !wait_ilde state failed!\n");
+}
+
+static void fu740_pcie_init_phy(struct fu740_pcie *afp)
+{
+	/* Enable phy cr_para_sel interfaces */
+	writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PHY0_CR_PARA_SEL);
+	writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_PHY1_CR_PARA_SEL);
+
+	/*
+	 * Wait 10 cr_para cycles to guarantee that the registers are ready
+	 * to be edited.
+	 */
+	ndelay(10);
+
+	/* Set PHY AC termination mode */
+	fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE0_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE1_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE2_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(0, PCIEX8MGMT_PHY_LANE3_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE0_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE1_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE2_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+	fu740_phyregwrite(1, PCIEX8MGMT_PHY_LANE3_BASE, PCIEX8MGMT_PHY_INIT_VAL, afp);
+}
+
+static void fu740_pcie_ltssm_enable(struct device *dev)
+{
+	struct fu740_pcie *afp = dev_get_drvdata(dev);
+
+	/* Enable LTSSM */
+	writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_APP_LTSSM_ENABLE);
+}
+
+static int fu740_pcie_start_link(struct dw_pcie *pci)
+{
+	struct device *dev = pci->dev;
+
+	/* Start LTSSM. */
+	fu740_pcie_ltssm_enable(dev);
+	return 0;
+}
+
+static int fu740_pcie_host_init(struct pcie_port *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct fu740_pcie *afp = to_fu740_pcie(pci);
+	struct device *dev = pci->dev;
+	int ret;
+
+	/* Power on reset */
+	fu740_pcie_drive_reset(afp);
+
+	/* Enable pcieauxclk */
+	ret = clk_prepare_enable(afp->pcie_aux);
+	if (ret)
+		dev_err(dev, "unable to enable pcie_aux clock\n");
+
+	/*
+	 * Assert hold_phy_rst (hold the controller LTSSM in reset after
+	 * power_up_rst_n for register programming with cr_para)
+	 */
+	writel_relaxed(0x1, afp->mgmt_base + PCIEX8MGMT_APP_HOLD_PHY_RST);
+
+	/* Deassert power_up_rst_n */
+	ret = reset_control_deassert(afp->rst);
+	if (ret)
+		dev_err(dev, "unable to deassert pcie_power_up_rst_n\n");
+
+	fu740_pcie_init_phy(afp);
+
+	/* Disable pcieauxclk */
+	clk_disable_unprepare(afp->pcie_aux);
+	/* Clear hold_phy_rst */
+	writel_relaxed(0x0, afp->mgmt_base + PCIEX8MGMT_APP_HOLD_PHY_RST);
+	/* Enable pcieauxclk */
+	ret = clk_prepare_enable(afp->pcie_aux);
+	/* Set RC mode */
+	writel_relaxed(0x4, afp->mgmt_base + PCIEX8MGMT_DEVICE_TYPE);
+
+	return 0;
+}
+
+static const struct dw_pcie_host_ops fu740_pcie_host_ops = {
+	.host_init = fu740_pcie_host_init,
+};
+
+static const struct dw_pcie_ops dw_pcie_ops = {
+	.start_link = fu740_pcie_start_link,
+};
+
+static int fu740_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dw_pcie *pci;
+	struct fu740_pcie *afp;
+	int ret;
+
+	afp = devm_kzalloc(dev, sizeof(*afp), GFP_KERNEL);
+	if (!afp)
+		return -ENOMEM;
+	pci = &afp->pci;
+	pci->dev = dev;
+	pci->ops = &dw_pcie_ops;
+	pci->pp.ops = &fu740_pcie_host_ops;
+
+	/* SiFive specific region: mgmt */
+	afp->mgmt_base = devm_platform_ioremap_resource_byname(pdev, "mgmt");
+	if (IS_ERR(afp->mgmt_base))
+		return PTR_ERR(afp->mgmt_base);
+
+	/* Fetch GPIOs */
+	afp->reset = devm_gpiod_get_optional(dev, "reset-gpios", GPIOD_OUT_LOW);
+	if (IS_ERR(afp->reset)) {
+		dev_err(dev, "unable to get reset-gpios\n");
+		return ret;
+	}
+	afp->pwren = devm_gpiod_get_optional(dev, "pwren-gpios", GPIOD_OUT_LOW);
+	if (IS_ERR(afp->pwren)) {
+		dev_err(dev, "unable to get pwren-gpios\n");
+		return ret;
+	}
+
+	/* Fetch clocks */
+	afp->pcie_aux = devm_clk_get(dev, "pcie_aux");
+	if (IS_ERR(afp->pcie_aux))
+		return dev_err_probe(dev, PTR_ERR(afp->pcie_aux),
+					     "pcie_aux clock source missing or invalid\n");
+
+	/* Fetch reset */
+	afp->rst = devm_reset_control_get_exclusive(dev, NULL);
+	if (IS_ERR(afp->rst))
+		return dev_err_probe(dev, PTR_ERR(afp->rst), "unable to get reset\n");
+
+	platform_set_drvdata(pdev, afp);
+
+	ret = dw_pcie_host_init(&pci->pp);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void fu740_pcie_shutdown(struct platform_device *pdev)
+{
+	struct fu740_pcie *afp = platform_get_drvdata(pdev);
+
+	/* Bring down link, so bootloader gets clean state in case of reboot */
+	fu740_pcie_assert_reset(afp);
+}
+
+static const struct of_device_id fu740_pcie_of_match[] = {
+	{ .compatible = "sifive,fu740-pcie", },
+	{},
+};
+
+static struct platform_driver fu740_pcie_driver = {
+	.driver = {
+		   .name = "fu740-pcie",
+		   .of_match_table = fu740_pcie_of_match,
+		   .suppress_bind_attrs = true,
+	},
+	.probe = fu740_pcie_probe,
+	.shutdown = fu740_pcie_shutdown,
+};
+
+builtin_platform_driver(fu740_pcie_driver);
-- 
2.30.2

[PATCH v3 6/6] riscv: dts: Add PCIe support for the SiFive FU740-C000 SoC

[Greentime Hu]

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
---
 arch/riscv/boot/dts/sifive/fu740-c000.dtsi | 33 ++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/arch/riscv/boot/dts/sifive/fu740-c000.dtsi b/arch/riscv/boot/dts/sifive/fu740-c000.dtsi
index d1bb22b11920..b2317c8e3a80 100644
--- a/arch/riscv/boot/dts/sifive/fu740-c000.dtsi
+++ b/arch/riscv/boot/dts/sifive/fu740-c000.dtsi
@@ -158,6 +158,7 @@ prci: clock-controller@10000000 {
 			reg = <0x0 0x10000000 0x0 0x1000>;
 			clocks = <&hfclk>, <&rtcclk>;
 			#clock-cells = <1>;
+			#reset-cells = <1>;
 		};
 		uart0: serial@10010000 {
 			compatible = "sifive,fu740-c000-uart", "sifive,uart0";
@@ -288,5 +289,37 @@ gpio: gpio@10060000 {
 			clocks = <&prci PRCI_CLK_PCLK>;
 			status = "disabled";
 		};
+		pcie@e00000000 {
+			compatible = "sifive,fu740-pcie";
+			#address-cells = <3>;
+			#size-cells = <2>;
+			#interrupt-cells = <1>;
+			reg = <0xe 0x00000000 0x0 0x80000000>,
+			      <0xd 0xf0000000 0x0 0x10000000>,
+			      <0x0 0x100d0000 0x0 0x1000>;
+			reg-names = "dbi", "config", "mgmt";
+			device_type = "pci";
+			dma-coherent;
+			bus-range = <0x0 0xff>;
+			ranges = <0x81000000  0x0 0x60080000  0x0 0x60080000 0x0 0x10000>,      /* I/O */
+				 <0x82000000  0x0 0x60090000  0x0 0x60090000 0x0 0xff70000>,    /* mem */
+				 <0x82000000  0x0 0x70000000  0x0 0x70000000 0x0 0x1000000>,    /* mem */
+				 <0xc3000000 0x20 0x00000000 0x20 0x00000000 0x20 0x00000000>;  /* mem prefetchable */
+			num-lanes = <0x8>;
+			interrupts = <56>, <57>, <58>, <59>, <60>, <61>, <62>, <63>, <64>;
+			interrupt-names = "msi", "inta", "intb", "intc", "intd";
+			interrupt-parent = <&plic0>;
+			interrupt-map-mask = <0x0 0x0 0x0 0x7>;
+			interrupt-map = <0x0 0x0 0x0 0x1 &plic0 57>,
+					<0x0 0x0 0x0 0x2 &plic0 58>,
+					<0x0 0x0 0x0 0x3 &plic0 59>,
+					<0x0 0x0 0x0 0x4 &plic0 60>;
+			clock-names = "pcie_aux";
+			clocks = <&prci PRCI_CLK_PCIE_AUX>;
+			pwren-gpios = <&gpio 5 0>;
+			reset-gpios = <&gpio 8 0>;
+			resets = <&prci 4>;
+			status = "okay";
+		};
 	};
 };
-- 
2.30.2

Re: [PATCH v3 1/6] clk: sifive: Add pcie_aux clock in prci driver for PCIe driver

[Stephen Boyd]

Quoting Greentime Hu (2021-03-31 02:26:00)
> We add pcie_aux clock in this patch so that pcie driver can use
> clk_prepare_enable() and clk_disable_unprepare() to enable and disable
> pcie_aux clock.
> 
> Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
> ---

With robot fix

Acked-by: Stephen Boyd <sboyd@kernel.org>

Re: [PATCH v3 2/6] clk: sifive: Use reset-simple in prci driver for PCIe driver

[Stephen Boyd]

Quoting Greentime Hu (2021-03-31 02:26:01)
> We use reset-simple in this patch so that pcie driver can use
> devm_reset_control_get() to get this reset data structure and use
> reset_control_deassert() to deassert pcie_power_up_rst_n.
> 
> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
> Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
> ---

Acked-by: Stephen Boyd <sboyd@kernel.org>