Re: [PATCH v4] usb: dwc3: enable CCI support for AMD-xilinx DWC3 controller
From: Thinh Nguyen
Date: Mon Jul 08 2024 - 19:10:23 EST
Hi,
On Mon, Jul 08, 2024, Radhey Shyam Pandey wrote:
> The GSBUSCFG0 register bits [31:16] are used to configure the cache type
> settings of the descriptor and data write/read transfers (Cacheable,
> Bufferable/Posted). When CCI is enabled in the design, DWC3 core GSBUSCFG0
> cache bits must be updated to support CCI enabled transfers in USB.
>
> To program GSBUSCFG0 cache bits create a software node property
> in AMD-xilinx dwc3 glue driver and pass it to dwc3 core. The core
> then reads this property value and configures it in dwc3_core_init()
> sequence.
>
> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxx>
> ---
> Changes for v4:
>
> - Pass swnode GSBUSCFG0 cache property from glue driver based on
> dma-coherent flag.
> - Introduce function dwc3_get_software_properties().
> - Rename DWC3_GSBUSCFG0_REQINFO_MASK.
> - Use DWC3_GSBUSCFG0_REQINFO(n) and get rid of mask shift define.
> - Rename dwc3 member gsbuscfg0_reqinfo and change it type to u32
> and define 0xffffffff as unspecified.
> - In comment dwc3_get_software_properties() description also mention
> "non-DT (non-ABI) properties".
>
> Changes for v3:
> - In v2 review as suggested by Thinh Nguyen, switch to swnode
> implementation for passing GSBUSCFG0 cache bits from AMD-xilinx
> dwc3 glue driver to core driver.
>
> Changes for v2:
> - Make GSBUSCFG0 configuration specific to AMD-xilinx platform.
> Taken reference from existing commit ec5eb43813a4 ("usb: dwc3: core:
> add support for realtek SoCs custom's global register start address")
>
> v1 link:
> https://urldefense.com/v3/__https://lore.kernel.org/all/20231013053448.11056-1-piyush.mehta@amd.com__;!!A4F2R9G_pg!am1D9hRrSGeDKIL_gkCMiaw4qKGYni_j2_GzjGvdkTuJCqUcX2OQtJKtrvZKdQ6DLvT6uu7FEIf1OiB8-vjozf7E-SlrKQ$
> ---
> drivers/usb/dwc3/core.c | 38 ++++++++++++++++++++++++++++++++++
> drivers/usb/dwc3/core.h | 8 +++++++
> drivers/usb/dwc3/dwc3-xilinx.c | 29 ++++++++++++++++++++++++++
> 3 files changed, 75 insertions(+)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index cb82557678dd..fe216a6ff652 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -23,6 +23,7 @@
> #include <linux/delay.h>
> #include <linux/dma-mapping.h>
> #include <linux/of.h>
> +#include <linux/of_address.h>
We no long need to include this in core.c right?
> #include <linux/of_graph.h>
> #include <linux/acpi.h>
> #include <linux/pinctrl/consumer.h>
> @@ -599,6 +600,18 @@ static void dwc3_cache_hwparams(struct dwc3 *dwc)
> parms->hwparams9 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS9);
> }
>
> +static void dwc3_config_soc_bus(struct dwc3 *dwc)
> +{
> + if (dwc->gsbuscfg0_reqinfo != DWC3_GSBUSCFG0_REQINFO_DEF) {
> + u32 reg;
> +
> + reg = dwc3_readl(dwc->regs, DWC3_GSBUSCFG0);
> + reg &= ~DWC3_GSBUSCFG0_REQINFO(~0);
> + reg |= DWC3_GSBUSCFG0_REQINFO(dwc->gsbuscfg0_reqinfo);
> + dwc3_writel(dwc->regs, DWC3_GSBUSCFG0, reg);
> + }
> +}
> +
> static int dwc3_core_ulpi_init(struct dwc3 *dwc)
> {
> int intf;
> @@ -1338,6 +1351,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
>
> dwc3_set_incr_burst_type(dwc);
>
> + dwc3_config_soc_bus(dwc);
> +
> ret = dwc3_phy_power_on(dwc);
> if (ret)
> goto err_exit_phy;
> @@ -1756,6 +1771,27 @@ static void dwc3_get_properties(struct dwc3 *dwc)
> dwc->tx_fifo_resize_max_num = tx_fifo_resize_max_num;
> }
>
> +static void dwc3_get_software_properties(struct dwc3 *dwc)
Can we move this above dwc3_get_properties(). I'd call this within
dwc3_get_properties(), but it's fine even if you leave it separate for
now. That'll help reduce the code footprint when we refactor and move
the other software properties in here.
> +{
> + struct device *tmpdev;
> + u16 gsbuscfg0_reqinfo;
> + int ret;
> +
> + dwc->gsbuscfg0_reqinfo = DWC3_GSBUSCFG0_REQINFO_DEF;
> +
> + /*
> + * Iterate over all parent nodes for finding swnode properties
> + * and non-DT (non-ABI) properties.
> + */
> + for (tmpdev = dwc->dev; tmpdev; tmpdev = tmpdev->parent) {
> + ret = device_property_read_u16(tmpdev,
> + "snps,gsbuscfg0-reqinfo",
> + &gsbuscfg0_reqinfo);
> + if (!ret)
> + dwc->gsbuscfg0_reqinfo = gsbuscfg0_reqinfo;
> + }
> +}
> +
> /* check whether the core supports IMOD */
> bool dwc3_has_imod(struct dwc3 *dwc)
> {
> @@ -2090,6 +2126,8 @@ static int dwc3_probe(struct platform_device *pdev)
>
> dwc3_get_properties(dwc);
>
> + dwc3_get_software_properties(dwc);
> +
> dwc->reset = devm_reset_control_array_get_optional_shared(dev);
> if (IS_ERR(dwc->reset)) {
> ret = PTR_ERR(dwc->reset);
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 3781c736c1a1..e04640662d36 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -194,6 +194,10 @@
> #define DWC3_GSBUSCFG0_INCRBRSTENA (1 << 0) /* undefined length enable */
> #define DWC3_GSBUSCFG0_INCRBRST_MASK 0xff
>
> +/* Global SoC Bus Configuration Register: AHB-prot/AXI-cache/OCP-ReqInfo */
> +#define DWC3_GSBUSCFG0_REQINFO(n) (((n) & 0xffff) << 16)
> +#define DWC3_GSBUSCFG0_REQINFO_DEF 0xffffffff
Can we rename this to DWC3_GSBUSCFG0_REQINFO_UNSPECIFIED. "DEF" implies
a valid default value.
> +
> /* Global Debug LSP MUX Select */
> #define DWC3_GDBGLSPMUX_ENDBC BIT(15) /* Host only */
> #define DWC3_GDBGLSPMUX_HOSTSELECT(n) ((n) & 0x3fff)
> @@ -1153,6 +1157,9 @@ struct dwc3_scratchpad_array {
> * @num_ep_resized: carries the current number endpoints which have had its tx
> * fifo resized.
> * @debug_root: root debugfs directory for this device to put its files in.
> + * @gsbuscfg0_reqinfo: store GSBUSCFG0.DATRDREQINFO, DESRDREQINFO,
> + * DATWRREQINFO, and DESWRREQINFO value passed from
> + * glue driver.
> */
> struct dwc3 {
> struct work_struct drd_work;
> @@ -1380,6 +1387,7 @@ struct dwc3 {
> int last_fifo_depth;
> int num_ep_resized;
> struct dentry *debug_root;
> + u32 gsbuscfg0_reqinfo;
> };
>
> #define INCRX_BURST_MODE 0
> diff --git a/drivers/usb/dwc3/dwc3-xilinx.c b/drivers/usb/dwc3/dwc3-xilinx.c
> index 6095f4dee6ce..bb4d894c16e9 100644
> --- a/drivers/usb/dwc3/dwc3-xilinx.c
> +++ b/drivers/usb/dwc3/dwc3-xilinx.c
> @@ -246,6 +246,31 @@ static const struct of_device_id dwc3_xlnx_of_match[] = {
> };
> MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
>
> +static int dwc3_set_swnode(struct device *dev)
> +{
> + struct device_node *np = dev->of_node, *dwc3_np;
> + struct property_entry props[2];
> + int prop_idx = 0, ret = 0;
> +
> + dwc3_np = of_get_compatible_child(np, "snps,dwc3");
> + if (!dwc3_np) {
> + ret = -ENODEV;
> + dev_err(dev, "failed to find dwc3 core child\n");
> + return ret;
> + }
> +
> + memset(props, 0, sizeof(struct property_entry) * ARRAY_SIZE(props));
> + if (of_dma_is_coherent(dwc3_np))
> + props[prop_idx++] = PROPERTY_ENTRY_U16("snps,gsbuscfg0-reqinfo",
> + 0xffff);
> + of_node_put(dwc3_np);
> +
> + if (prop_idx)
> + ret = device_create_managed_software_node(dev, props, NULL);
> +
> + return ret;
> +}
> +
> static int dwc3_xlnx_probe(struct platform_device *pdev)
> {
> struct dwc3_xlnx *priv_data;
> @@ -288,6 +313,10 @@ static int dwc3_xlnx_probe(struct platform_device *pdev)
> if (ret)
> goto err_clk_put;
>
> + ret = dwc3_set_swnode(dev);
> + if (ret)
> + goto err_clk_put;
> +
> ret = of_platform_populate(np, NULL, NULL, dev);
> if (ret)
> goto err_clk_put;
>
> base-commit: 0b58e108042b0ed28a71cd7edf5175999955b233
> --
> 2.34.1
>
Beside a couple very minor comments, this looks great to me!
I'll be on vacation in a couple of days, can you send v5 soon?
Thanks!
Thinh