[PATCH v8 0/2 RESEND] add the Amlogic Meson PCIe controller driver

[PATCH v8 0/2 RESEND] add the Amlogic Meson PCIe controller driver

[Hanjie Lin]

The Amlogic Meson PCIe host controller is based on the Synopsys DesignWare
PCI core. This patchset add the driver and dt-bindings of the controller.

Changes since v7: [6]
 - include files in alphabetical order
 - get rid of unused MACROs and variables
 - optimize meson_pcie_link_up() while loop
 - correct cover-letter version

Changes since v6: [5]
 - fix bad usage of ERR_PTR(ENXIO)
 - fix meson_pcie_rd_own_conf() when read PCI_CLASS_DEVICE reg 

Changes since v5: [4]
 - update MAINTAINER file in alphabetical order
 - remove meaningless comment
 - use ERR_PTR function instead of (void *) cast
 - use is_power_of_2(size) instead of size & (size - 1)
 - add comment for PCI_CLASS_REVISION register operation
 
Changes since v4: [3]
 - fix kbuild test robot and compile warnings

Changes since v3: [2]
 - modify subject format
 - update Kconfig
 - update MAINTAINER file
 - add comment and error handle for meson_pcie_get_mem_shared()
 - drop useless initialization code
 - add comment for meson_size_to_payload()
 - optimize meson_pcie_establish_link() return code
 - optimize meson_pcie_enable_interrupts() redundant function
 - drop device_attch related code
 - drop dw_pcie_ops read_dbi and write_dbi function
 - add error handle for meson_add_pcie_port() when probe

Changes since v2: [1]
 - abandon phy driver, move reset to the controller
 - use devm_add_action_or_reset() to use clock res
 - format correcting

Changes since v1: [0]
 - use gpio lib instead open code
 - move 'apb' and 'port' reset from phy driver
 - format correcting

[0] : https://lkml.kernel.org/r/1534227522-186798-1-git-send-email-hanjie.lin@amlogic.com
[1] : https://lkml.kernel.org/r/1535096165-45827-1-git-send-email-hanjie.lin@amlogic.com
[2] : https://lkml.kernel.org/r/1537509820-52040-1-git-send-email-hanjie.lin@amlogic.com 
[3] : https://lkml.kernel.org/r/1538999834-156423-3-git-send-email-hanjie.lin@amlogic.com
[4] : https://lkml.kernel.org/r/1539049990-30810-1-git-send-email-hanjie.lin@amlogic.com
[5] : https://lkml.kernel.org/r/1542876836-191355-1-git-send-email-hanjie.lin@amlogic.com
[6] : https://lkml.kernel.org/r/1544097760-85834-1-git-send-email-hanjie.lin@amlogic.com

Yue Wang (2):
  dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe
    controller
  PCI: amlogic: Add the Amlogic Meson PCIe controller driver

 .../devicetree/bindings/pci/amlogic,meson-pcie.txt |  70 +++
 MAINTAINERS                                        |   7 +
 drivers/pci/controller/dwc/Kconfig                 |  10 +
 drivers/pci/controller/dwc/Makefile                |   1 +
 drivers/pci/controller/dwc/pci-meson.c             | 595 +++++++++++++++++++++
 5 files changed, 683 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
 create mode 100644 drivers/pci/controller/dwc/pci-meson.c

-- 
2.7.4

[PATCH v8 1/2] dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller

[Hanjie Lin]

From: Yue Wang <yue.wang@amlogic.com>

The Amlogic Meson PCIe host controller is based on the Synopsys DesignWare
PCI core. This patch adds documentation for the DT bindings in Meson PCIe
controller.

Signed-off-by: Yue Wang <yue.wang@amlogic.com>
Signed-off-by: Hanjie Lin <hanjie.lin@amlogic.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/pci/amlogic,meson-pcie.txt | 70 ++++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt

diff --git a/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt b/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
new file mode 100644
index 0000000..12b18f8
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
@@ -0,0 +1,70 @@
+Amlogic Meson AXG DWC PCIE SoC controller
+
+Amlogic Meson PCIe host controller is based on the Synopsys DesignWare PCI core.
+It shares common functions with the PCIe DesignWare core driver and
+inherits common properties defined in
+Documentation/devicetree/bindings/pci/designware-pci.txt.
+
+Additional properties are described here:
+
+Required properties:
+- compatible:
+	should contain "amlogic,axg-pcie" to identify the core.
+- reg:
+	should contain the configuration address space.
+- reg-names: Must be
+	- "elbi"	External local bus interface registers
+	- "cfg"		Meson specific registers
+	- "phy"		Meson PCIE PHY registers
+	- "config"	PCIe configuration space
+- reset-gpios: The GPIO to generate PCIe PERST# assert and deassert signal.
+- clocks: Must contain an entry for each entry in clock-names.
+- clock-names: Must include the following entries:
+	- "pclk"       PCIe GEN 100M PLL clock
+	- "port"       PCIe_x(A or B) RC clock gate
+	- "general"    PCIe Phy clock
+	- "mipi"       PCIe_x(A or B) 100M ref clock gate
+- resets: phandle to the reset lines.
+- reset-names: must contain "phy" "port" and "apb"
+       - "phy"         Share PHY reset
+       - "port"        Port A or B reset
+       - "apb"         Share APB reset
+- device_type:
+	should be "pci". As specified in designware-pcie.txt
+
+
+Example configuration:
+
+	pcie: pcie@f9800000 {
+			compatible = "amlogic,axg-pcie", "snps,dw-pcie";
+			reg = <0x0 0xf9800000 0x0 0x400000
+					0x0 0xff646000 0x0 0x2000
+					0x0 0xff644000 0x0 0x2000
+					0x0 0xf9f00000 0x0 0x100000>;
+			reg-names = "elbi", "cfg", "phy", "config";
+			reset-gpios = <&gpio GPIOX_19 GPIO_ACTIVE_HIGH>;
+			interrupts = <GIC_SPI 177 IRQ_TYPE_EDGE_RISING>;
+			#interrupt-cells = <1>;
+			interrupt-map-mask = <0 0 0 0>;
+			interrupt-map = <0 0 0 0 &gic GIC_SPI 179 IRQ_TYPE_EDGE_RISING>;
+			bus-range = <0x0 0xff>;
+			#address-cells = <3>;
+			#size-cells = <2>;
+			device_type = "pci";
+			ranges = <0x82000000 0 0 0x0 0xf9c00000 0 0x00300000>;
+
+			clocks = <&clkc CLKID_USB
+					&clkc CLKID_MIPI_ENABLE
+					&clkc CLKID_PCIE_A
+					&clkc CLKID_PCIE_CML_EN0>;
+			clock-names = "general",
+					"mipi",
+					"pclk",
+					"port";
+			resets = <&reset RESET_PCIE_PHY>,
+				<&reset RESET_PCIE_A>,
+				<&reset RESET_PCIE_APB>;
+			reset-names = "phy",
+					"port",
+					"apb";
+	};
-- 
2.7.4

Re: [PATCH v8 1/2] dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller

[Martin Blumenstingl]

Hi Rob, Hi Hanjie,

(sorry for being late with my question)

On Tue, Dec 18, 2018 at 9:05 AM Hanjie Lin <hanjie.lin@amlogic.com> wrote:
[...]
> +- reg-names: Must be
> +       - "elbi"        External local bus interface registers
> +       - "cfg"         Meson specific registers
> +       - "phy"         Meson PCIE PHY registers
I have learned that there are two PHY register designs:
- AXG only has a PCIe PHY
- G12A has a PHY which supports PCIe and USB 3.0. The PCIe part of
this PHY design is compatible with AXG, but this design also supports
a USB 3.0 port (it's an exclusive choice: either PCIe *or* USB 3.0)

The PCIe controller itself is identical on both, AXG and G12A.
This patch adds support for the AXG PCIe controller and PHY within one
device-tree node.

For G12A I propose to add a separate "phys" property with a phandle to
the "combo" PCIe and USB3.0 PHY - this can be part of a separate patch
though.
I would like to know whether it's OK that for AXG the PCIe PHY is
described in the same device-tree node as the PCIe controller (in
other words: we're not using a "phys" property here)?


Kind Regards
Martin

Re: [PATCH v8 1/2] dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller

[Hanjie Lin]

On 2018/12/19 7:14, Martin Blumenstingl wrote:
> Hi Rob, Hi Hanjie,
> 
> (sorry for being late with my question)
> 
> On Tue, Dec 18, 2018 at 9:05 AM Hanjie Lin <hanjie.lin@amlogic.com> wrote:
> [...]
>> +- reg-names: Must be
>> +       - "elbi"        External local bus interface registers
>> +       - "cfg"         Meson specific registers
>> +       - "phy"         Meson PCIE PHY registers
> I have learned that there are two PHY register designs:
> - AXG only has a PCIe PHY
> - G12A has a PHY which supports PCIe and USB 3.0. The PCIe part of
> this PHY design is compatible with AXG, but this design also supports
> a USB 3.0 port (it's an exclusive choice: either PCIe *or* USB 3.0)
> 
> The PCIe controller itself is identical on both, AXG and G12A.
> This patch adds support for the AXG PCIe controller and PHY within one
> device-tree node.
> 
> For G12A I propose to add a separate "phys" property with a phandle to
> the "combo" PCIe and USB3.0 PHY - this can be part of a separate patch
> though.
> I would like to know whether it's OK that for AXG the PCIe PHY is
> described in the same device-tree node as the PCIe controller (in
> other words: we're not using a "phys" property here)?
> 
> 
> Kind Regards
> Martin
> 
> .
> 

hi matrin,

We do had a dedicated PHY driver for a time at the begining
of this patch series, but we decided to remove it and integrate
into the controller driver after series reviews and disscussions,
and the main reason is it's too overkill to have a dedicated 
PHY driver which only do the RESET job.

Of course we can consider the dedicated PHY driver for G12A upstream
in future.

thanks
hanjie