This patch series documents the Xilinx Versal DWC3 controller. This also
adds a new Xilinx specific driver for adding new features in the future.
Changes in v2:
- Addressed review comments from v1
- merged normal and runtime suspend resume functions as they are
same
- Improved description of some register operations to avoid
confusion
- Updated commit log for patch 2/2 for better clarity.
Changes in v3:
- Removed snps,enable-hibernation property from the devicetree
binding.
Manish Narani (2):
dt-bindings: usb: dwc3-xilinx: Add documentation for Versal DWC3
Controller
usb: dwc3: Add driver for Xilinx platforms
.../devicetree/bindings/usb/dwc3-xilinx.txt | 17 +-
drivers/usb/dwc3/Kconfig | 9 +
drivers/usb/dwc3/Makefile | 1 +
drivers/usb/dwc3/dwc3-of-simple.c | 1 -
drivers/usb/dwc3/dwc3-xilinx.c | 334 ++++++++++++++++++
5 files changed, 359 insertions(+), 3 deletions(-)
create mode 100644 drivers/usb/dwc3/dwc3-xilinx.c
--
2.17.1
Add a new driver for supporting Xilinx platforms. This driver is used
for some sequence of operations required for Xilinx USB controllers.
This driver is also used to choose between PIPE clock coming from SerDes
and the Suspend Clock. Before the controller is out of reset, the clock
selection should be changed to PIPE clock in order to make the USB
controller work. There is a register added in Xilinx USB controller
register space for the same.
Signed-off-by: Manish Narani <[email protected]>
---
drivers/usb/dwc3/Kconfig | 9 +
drivers/usb/dwc3/Makefile | 1 +
drivers/usb/dwc3/dwc3-of-simple.c | 1 -
drivers/usb/dwc3/dwc3-xilinx.c | 334 ++++++++++++++++++++++++++++++
4 files changed, 344 insertions(+), 1 deletion(-)
create mode 100644 drivers/usb/dwc3/dwc3-xilinx.c
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index 7a2304565a73..0e00e6dfccd8 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -139,4 +139,13 @@ config USB_DWC3_QCOM
for peripheral mode support.
Say 'Y' or 'M' if you have one such device.
+config USB_DWC3_XILINX
+ tristate "Xilinx Platforms"
+ depends on (ARCH_ZYNQMP || ARCH_VERSAL) && OF
+ default USB_DWC3
+ help
+ Support Xilinx SoCs with DesignWare Core USB3 IP.
+ This driver handles both ZynqMP and Versal SoC operations.
+ Say 'Y' or 'M' if you have one such device.
+
endif
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index ae86da0dc5bd..add567578b1f 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -51,3 +51,4 @@ obj-$(CONFIG_USB_DWC3_MESON_G12A) += dwc3-meson-g12a.o
obj-$(CONFIG_USB_DWC3_OF_SIMPLE) += dwc3-of-simple.o
obj-$(CONFIG_USB_DWC3_ST) += dwc3-st.o
obj-$(CONFIG_USB_DWC3_QCOM) += dwc3-qcom.o
+obj-$(CONFIG_USB_DWC3_XILINX) += dwc3-xilinx.o
diff --git a/drivers/usb/dwc3/dwc3-of-simple.c b/drivers/usb/dwc3/dwc3-of-simple.c
index e62ecd22b3ed..71fd620c5161 100644
--- a/drivers/usb/dwc3/dwc3-of-simple.c
+++ b/drivers/usb/dwc3/dwc3-of-simple.c
@@ -172,7 +172,6 @@ static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
static const struct of_device_id of_dwc3_simple_match[] = {
{ .compatible = "rockchip,rk3399-dwc3" },
- { .compatible = "xlnx,zynqmp-dwc3" },
{ .compatible = "cavium,octeon-7130-usb-uctl" },
{ .compatible = "sprd,sc9860-dwc3" },
{ .compatible = "allwinner,sun50i-h6-dwc3" },
diff --git a/drivers/usb/dwc3/dwc3-xilinx.c b/drivers/usb/dwc3/dwc3-xilinx.c
new file mode 100644
index 000000000000..7e485951d2f7
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-xilinx.c
@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * dwc3-xilinx.c - Xilinx DWC3 controller specific glue driver
+ *
+ * Authors: Manish Narani <[email protected]>
+ * Anurag Kumar Vulisha <[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <linux/of_address.h>
+#include <linux/delay.h>
+#include <linux/firmware/xlnx-zynqmp.h>
+#include <linux/io.h>
+
+#include <linux/phy/phy.h>
+
+/* USB phy reset mask register */
+#define XLNX_USB_PHY_RST_EN 0x001C
+#define XLNX_PHY_RST_MASK 0x1
+
+/* Xilinx USB 3.0 IP Register */
+#define XLNX_USB_TRAFFIC_ROUTE_CONFIG 0x005C
+#define XLNX_USB_TRAFFIC_ROUTE_FPD 0x1
+
+/* Versal USB Reset ID */
+#define VERSAL_USB_RESET_ID 0xC104036
+
+#define XLNX_USB_FPD_PIPE_CLK 0x7c
+#define PIPE_CLK_DESELECT 1
+#define PIPE_CLK_SELECT 0
+#define XLNX_USB_FPD_POWER_PRSNT 0x80
+#define PIPE_POWER_ON 1
+#define PIPE_POWER_OFF 0
+
+struct dwc3_xlnx {
+ int num_clocks;
+ struct clk_bulk_data *clks;
+ struct device *dev;
+ void __iomem *regs;
+ int (*pltfm_init)(struct dwc3_xlnx *data);
+};
+
+static void dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx *priv_data, bool mask)
+{
+ u32 reg;
+
+ /*
+ * Enable or disable ULPI PHY reset from USB Controller.
+ * This does not actually reset the phy, but just controls
+ * whether USB controller can or cannot reset ULPI PHY.
+ */
+ reg = readl(priv_data->regs + XLNX_USB_PHY_RST_EN);
+
+ if (mask)
+ reg &= ~XLNX_PHY_RST_MASK;
+ else
+ reg |= XLNX_PHY_RST_MASK;
+
+ writel(reg, priv_data->regs + XLNX_USB_PHY_RST_EN);
+}
+
+static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
+{
+ struct device *dev = priv_data->dev;
+ int ret;
+
+ dwc3_xlnx_mask_phy_rst(priv_data, false);
+
+ /* Assert and De-assert reset */
+ ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
+ PM_RESET_ACTION_ASSERT);
+ if (ret < 0) {
+ dev_err_probe(dev, ret, "failed to assert Reset\n");
+ return ret;
+ }
+
+ ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
+ PM_RESET_ACTION_RELEASE);
+ if (ret < 0) {
+ dev_err_probe(dev, ret, "failed to De-assert Reset\n");
+ return ret;
+ }
+
+ dwc3_xlnx_mask_phy_rst(priv_data, true);
+
+ return 0;
+}
+
+static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
+{
+ struct device *dev = priv_data->dev;
+ struct reset_control *crst, *hibrst, *apbrst;
+ struct phy *usb3_phy;
+ int ret;
+ u32 reg;
+
+ crst = devm_reset_control_get_exclusive(dev, "usb_crst");
+ if (IS_ERR(crst)) {
+ ret = PTR_ERR(crst);
+ dev_err_probe(dev, ret,
+ "failed to get core reset signal\n");
+ goto err;
+ }
+
+ hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
+ if (IS_ERR(hibrst)) {
+ ret = PTR_ERR(hibrst);
+ dev_err_probe(dev, ret,
+ "failed to get hibernation reset signal\n");
+ goto err;
+ }
+
+ apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
+ if (IS_ERR(apbrst)) {
+ ret = PTR_ERR(apbrst);
+ dev_err_probe(dev, ret,
+ "failed to get APB reset signal\n");
+ goto err;
+ }
+
+ ret = reset_control_assert(crst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to assert core reset\n");
+ goto err;
+ }
+
+ ret = reset_control_assert(hibrst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to assert hibernation reset\n");
+ goto err;
+ }
+
+ ret = reset_control_assert(apbrst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to assert APB reset\n");
+ goto err;
+ }
+
+ usb3_phy = devm_phy_get(dev, "usb3-phy");
+
+ ret = phy_init(usb3_phy);
+ if (ret < 0) {
+ phy_exit(usb3_phy);
+ goto err;
+ }
+
+ ret = reset_control_deassert(apbrst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to release APB reset\n");
+ goto err;
+ }
+
+ /* Set PIPE Power Present signal in FPD Power Present Register*/
+ writel(PIPE_POWER_ON, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
+
+ /* Set the PIPE Clock Select bit in FPD PIPE Clock register */
+ writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
+
+ ret = reset_control_deassert(crst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to release core reset\n");
+ goto err;
+ }
+
+ ret = reset_control_deassert(hibrst);
+ if (ret < 0) {
+ dev_err(dev, "Failed to release hibernation reset\n");
+ goto err;
+ }
+
+ ret = phy_power_on(usb3_phy);
+ if (ret < 0) {
+ phy_exit(usb3_phy);
+ goto err;
+ }
+
+ /*
+ * This routes the USB DMA traffic to go through FPD path instead
+ * of reaching DDR directly. This traffic routing is needed to
+ * make SMMU and CCI work with USB DMA.
+ */
+ if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
+ reg = readl(priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
+ reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
+ writel(reg, priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
+ }
+
+err:
+ return ret;
+}
+
+static const struct of_device_id dwc3_xlnx_of_match[] = {
+ {
+ .compatible = "xlnx,zynqmp-dwc3",
+ .data = &dwc3_xlnx_init_zynqmp,
+ },
+ {
+ .compatible = "xlnx,versal-dwc3",
+ .data = &dwc3_xlnx_init_versal,
+ },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
+
+static int dwc3_xlnx_probe(struct platform_device *pdev)
+{
+ struct dwc3_xlnx *priv_data;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ const struct of_device_id *match;
+ void __iomem *regs;
+ int ret;
+
+ priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
+ if (!priv_data)
+ return -ENOMEM;
+
+ regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(regs)) {
+ ret = PTR_ERR(regs);
+ dev_err_probe(dev, ret, "failed to map registers\n");
+ return ret;
+ }
+
+ match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
+
+ priv_data->pltfm_init = match->data;
+ priv_data->regs = regs;
+ priv_data->dev = dev;
+
+ platform_set_drvdata(pdev, priv_data);
+
+ ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
+ if (ret < 0)
+ return ret;
+
+ priv_data->num_clocks = ret;
+
+ ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
+ if (ret)
+ return ret;
+
+ ret = priv_data->pltfm_init(priv_data);
+ if (ret)
+ goto err_clk_put;
+
+ ret = of_platform_populate(np, NULL, NULL, dev);
+ if (ret)
+ goto err_clk_put;
+
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ pm_suspend_ignore_children(dev, false);
+ pm_runtime_get_sync(dev);
+
+ return 0;
+
+err_clk_put:
+ clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
+ clk_bulk_put_all(priv_data->num_clocks, priv_data->clks);
+
+ return ret;
+}
+
+static int dwc3_xlnx_remove(struct platform_device *pdev)
+{
+ struct dwc3_xlnx *priv_data = platform_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+
+ of_platform_depopulate(dev);
+
+ clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
+ clk_bulk_put_all(priv_data->num_clocks, priv_data->clks);
+ priv_data->num_clocks = 0;
+
+ pm_runtime_disable(dev);
+ pm_runtime_put_noidle(dev);
+ pm_runtime_set_suspended(dev);
+
+ return 0;
+}
+
+static int __maybe_unused dwc3_xlnx_suspend_common(struct device *dev)
+{
+ struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
+
+ clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
+
+ return 0;
+}
+
+static int __maybe_unused dwc3_xlnx_resume_common(struct device *dev)
+{
+ struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
+
+ return clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
+}
+
+static int __maybe_unused dwc3_xlnx_runtime_idle(struct device *dev)
+{
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_autosuspend(dev);
+
+ return 0;
+}
+
+static UNIVERSAL_DEV_PM_OPS(dwc3_xlnx_dev_pm_ops, dwc3_xlnx_suspend_common,
+ dwc3_xlnx_resume_common, dwc3_xlnx_runtime_idle);
+
+static struct platform_driver dwc3_xlnx_driver = {
+ .probe = dwc3_xlnx_probe,
+ .remove = dwc3_xlnx_remove,
+ .driver = {
+ .name = "dwc3-xilinx",
+ .of_match_table = dwc3_xlnx_of_match,
+ .pm = &dwc3_xlnx_dev_pm_ops,
+ },
+};
+
+module_platform_driver(dwc3_xlnx_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Xilinx DWC3 controller specific glue driver");
+MODULE_AUTHOR("Manish Narani <[email protected]>");
+MODULE_AUTHOR("Anurag Kumar Vulisha <[email protected]>");
--
2.17.1
Hi,
Michael Grzeschik <[email protected]> writes:
> On Tue, Dec 15, 2020 at 12:24:51PM +0530, Manish Narani wrote:
>>Add a new driver for supporting Xilinx platforms. This driver is used
>>for some sequence of operations required for Xilinx USB controllers.
>>This driver is also used to choose between PIPE clock coming from SerDes
>>and the Suspend Clock. Before the controller is out of reset, the clock
>>selection should be changed to PIPE clock in order to make the USB
>>controller work. There is a register added in Xilinx USB controller
>>register space for the same.
>
> I tried out this driver with the vanilla kernel on an zynqmp. Without
> this patch the USB-Gadget is already acting buggy. In the gadget mode,
> some iterations of plug/unplug results to an stalled gadget which will
> never come back without a reboot.
>
> With the corresponding code of this driver (reset assert, clk modify,
> reset deassert) in the downstream kernels phy driver we found out it is
> totaly stable. But using this exact glue driver which should do the same
> as the downstream code, the gadget still was buggy the way described
> above.
>
> I suspect the difference lays in the different order of operations.
> While the downstream code is runing the resets inside the phy driver
> which is powered and initialized in the dwc3-core itself. With this glue
> layser approach of this patch the whole phy init is done before even
> touching dwc3-core in any way. It seems not to have the same effect,
> though.
>
> If really the order of operations is limiting us, we probably need
> another solution than this glue layer. Any Ideas?
might be a good idea to collect dwc3 trace events. Can you do that?
--
balbi