From: Balaji Selvanathan Date: Wed, 3 Dec 2025 11:07:33 +0000 (+0530) Subject: arch: arm: mach-snapdragon: Auto-detect USB SSPHY driver support X-Git-Tag: v2026.07-rc1~8^2~21 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5ebc47d984c4d510ceec4748e7d86451b72b6577;p=thirdparty%2Fu-boot.git arch: arm: mach-snapdragon: Auto-detect USB SSPHY driver support Automatically detect super-speed USB PHY driver availability and skip the USB speed fixup if driver is available, eliminating the need for manual configuration. Previously, U-Boot unconditionally limited USB to high-speed mode on all Qualcomm platforms because most lacked super-speed PHY drivers. This change implements runtime detection that checks if a PHY driver exists for the super-speed PHY node referenced by the DWC3 controller. The fixup is automatically skipped when a compatible driver is found, allowing the hardware to operate at full capability. Platforms without super-speed PHY drivers continue to receive the fixup automatically. Signed-off-by: Balaji Selvanathan [casey: rebased on flat-dwc3 dt support + fix Balaji's signoff] [casey: make erroneous printf() a debug() again] Link: https://patch.msgid.link/20251203110735.1959862-5-balaji.selvanathan@oss.qualcomm.com Signed-off-by: Casey Connolly --- diff --git a/arch/arm/mach-snapdragon/of_fixup.c b/arch/arm/mach-snapdragon/of_fixup.c index 286541c8edc..1298b774c1e 100644 --- a/arch/arm/mach-snapdragon/of_fixup.c +++ b/arch/arm/mach-snapdragon/of_fixup.c @@ -4,7 +4,7 @@ * * This file implements runtime fixups for Qualcomm DT to improve * compatibility with U-Boot. This includes adjusting the USB nodes - * to only use USB high-speed. + * to only use USB high-speed if SSPHY driver is not available. * * We use OF_LIVE for this rather than early FDT fixup for a couple * of reasons: it has a much nicer API, is most likely more efficient, @@ -21,26 +21,107 @@ #include #include #include +#include +#include #include #include #include +#include #include #include -/* U-Boot only supports USB high-speed mode on Qualcomm platforms with DWC3 - * USB controllers. Rather than requiring source level DT changes, we fix up - * DT here. This improves compatibility with upstream DT and simplifies the - * porting process for new devices. +/** + * find_ssphy_node() - Find the super-speed PHY node referenced by DWC3 + * @dwc3: DWC3 device node + * + * Returns: Pointer to SS-PHY node if found, NULL otherwise + */ +static struct device_node *find_ssphy_node(struct device_node *dwc3) +{ + const __be32 *phandles; + const char *phy_name; + int len, i, ret; + + phandles = of_get_property(dwc3, "phys", &len); + if (!phandles) + return NULL; + + len /= sizeof(*phandles); + + /* Iterate through PHY phandles to find the SS-PHY */ + for (i = 0; i < len; i++) { + ret = of_property_read_string_index(dwc3, "phy-names", i, &phy_name); + if (ret) + continue; + + /* Check if this is the super-speed PHY */ + if (!strncmp("usb3-phy", phy_name, strlen("usb3-phy")) || + !strncmp("usb3_phy", phy_name, strlen("usb3_phy"))) { + return of_find_node_by_phandle(NULL, be32_to_cpu(phandles[i])); + } + } + + return NULL; +} + +/** + * has_driver_for_node() - Check if any PHY driver can bind to this node + * @np: Device node to check + * + * Returns: true if a PHY driver with matching compatible string exists, false otherwise */ +static bool has_driver_for_node(struct device_node *np) +{ + struct driver *driver = ll_entry_start(struct driver, driver); + const int n_ents = ll_entry_count(struct driver, driver); + const char *compat_list, *compat; + int compat_length, i; + struct driver *entry; + + if (!np) + return false; + + /* Get compatible strings from the node */ + compat_list = of_get_property(np, "compatible", &compat_length); + if (!compat_list) + return false; + + /* Check each compatible string against PHY drivers only */ + for (i = 0; i < compat_length; i += strlen(compat) + 1) { + compat = compat_list + i; + + /* Iterate through all registered drivers */ + for (entry = driver; entry != driver + n_ents; entry++) { + const struct udevice_id *of_match = entry->of_match; + + /* Skip non-PHY drivers to improve performance */ + if (entry->id != UCLASS_PHY) + continue; + + if (!of_match) + continue; + + while (of_match->compatible) { + if (!strcmp(of_match->compatible, compat)) { + debug("Found PHY driver '%s' for SS-PHY compatible '%s'\n", + entry->name, compat); + return true; + } + of_match++; + } + } + } + + return false; +} + static int fixup_qcom_dwc3(struct device_node *root, struct device_node *glue_np, bool flat) { - struct device_node *dwc3; + struct device_node *dwc3, *ssphy_np; int ret, len, hsphy_idx = 1; const __be32 *phandles; const char *second_phy_name; - debug("Fixing up %s\n", glue_np->name); - /* New DT flattens the glue and controller into a single node. */ if (flat) { dwc3 = glue_np; @@ -54,30 +135,43 @@ static int fixup_qcom_dwc3(struct device_node *root, struct device_node *glue_np } } - /* Tell the glue driver to configure the wrapper for high-speed only operation */ - ret = of_write_prop(glue_np, "qcom,select-utmi-as-pipe-clk", 0, NULL); - if (ret) { - log_err("Failed to add property 'qcom,select-utmi-as-pipe-clk': %d\n", ret); - return ret; - } + debug("Checking USB configuration for %s\n", dwc3->name); phandles = of_get_property(dwc3, "phys", &len); len /= sizeof(*phandles); if (len == 1) { - log_debug("Only one phy, not a superspeed controller\n"); + debug("Only one phy, not a superspeed controller\n"); return 0; } - /* Figure out if the superspeed phy is present and if so then which phy is it? */ + /* Figure out if the superspeed phy is present */ ret = of_property_read_string_index(dwc3, "phy-names", 1, &second_phy_name); if (ret == -ENODATA) { - log_debug("Only one phy, not a super-speed controller\n"); + debug("Only one phy, not a super-speed controller\n"); return 0; } else if (ret) { log_err("Failed to read second phy name: %d\n", ret); return ret; } + /* Find the super-speed PHY node and check if a driver is available */ + ssphy_np = find_ssphy_node(dwc3); + if (ssphy_np && has_driver_for_node(ssphy_np)) { + debug("Skipping USB fixup for %s (SS-PHY driver available)\n", + dwc3->name); + return 0; + } + + /* No driver available - apply the fixup */ + debug("Applying USB high-speed fixup to %s\n", dwc3->name); + + /* Tell the glue driver to configure the wrapper for high-speed only operation */ + ret = of_write_prop(dwc3, "qcom,select-utmi-as-pipe-clk", 0, NULL); + if (ret) { + log_err("Failed to add property 'qcom,select-utmi-as-pipe-clk': %d\n", ret); + return ret; + } + /* * Determine which phy is the superspeed phy by checking the name of the second phy * since it is typically the superspeed one.