Use the coroutines framework to scan USB buses in parallel for better
performance. Tested on arm64 QEMU on a somewhat contrived example
(4 USB buses, each with one audio device, one keyboard, one mouse and
one tablet).
$ make qemu_arm64_defconfig
$ make -j$(nproc) CROSS_COMPILE="ccache aarch64-linux-gnu-"
$ qemu-system-aarch64 -M virt -nographic -cpu max -bios u-boot.bin \
$(for i in {1..4}; do echo -device qemu-xhci,id=xhci$i \
-device\ usb-{audio,kbd,mouse,tablet},bus=xhci$i.0; \
done)
The time spent in usb_init() is reported on the console and shows a
significant improvement with COROUTINES enabled.
** Without COROUTINES
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
scanning bus xhci_pci for devices... 6 USB Device(s) found
scanning bus xhci_pci for devices... 6 USB Device(s) found
scanning bus xhci_pci for devices... 6 USB Device(s) found
scanning bus xhci_pci for devices... 6 USB Device(s) found
USB: 4 bus(es) scanned in 5873 ms
** With COROUTINES
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Bus xhci_pci: Register 8001040 NbrPorts 8
Starting the controller
USB XHCI 1.00
Scanning 4 USB bus(es)... done
Bus xhci_pci: 6 USB device(s) found
Bus xhci_pci: 6 USB device(s) found
Bus xhci_pci: 6 USB device(s) found
Bus xhci_pci: 6 USB device(s) found
USB: 4 bus(es) scanned in 2213 ms
Signed-off-by: Jerome Forissier <[email protected]>
---
drivers/usb/host/usb-uclass.c | 152 +++++++++++++++++++++++++++++++++-
1 file changed, 149 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
index bfec303e7af..3104efe7f9e 100644
--- a/drivers/usb/host/usb-uclass.c
+++ b/drivers/usb/host/usb-uclass.c
@@ -9,6 +9,7 @@
#define LOG_CATEGORY UCLASS_USB
#include <bootdev.h>
+#include <coroutines.h>
#include <dm.h>
#include <errno.h>
#include <log.h>
@@ -18,6 +19,8 @@
#include <dm/lists.h>
#include <dm/uclass-internal.h>
+#include <time.h>
+
static bool asynch_allowed;
struct usb_uclass_priv {
@@ -221,6 +224,40 @@ int usb_stop(void)
return err;
}
+static int nbus;
+
+#if CONFIG_IS_ENABLED(COROUTINES)
+static void usb_scan_bus(struct udevice *bus, bool recurse)
+{
+ struct usb_bus_priv *priv;
+ struct udevice *dev;
+ int ret;
+
+ priv = dev_get_uclass_priv(bus);
+
+ assert(recurse); /* TODO: Support non-recusive */
+
+ debug("\n");
+ ret = usb_scan_device(bus, 0, USB_SPEED_FULL, &dev);
+ if (ret)
+ printf("Scanning bus %s failed, error %d\n", bus->name, ret);
+}
+
+static void usb_report_devices(struct uclass *uc)
+{
+ struct usb_bus_priv *priv;
+ struct udevice *bus;
+
+ uclass_foreach_dev(bus, uc) {
+ priv = dev_get_uclass_priv(bus);
+ printf("Bus %s: ", bus->name);
+ if (priv->next_addr == 0)
+ printf("No USB device found\n");
+ else
+ printf("%d USB device(s) found\n", priv->next_addr);
+ }
+}
+#else
static void usb_scan_bus(struct udevice *bus, bool recurse)
{
struct usb_bus_priv *priv;
@@ -240,7 +277,81 @@ static void usb_scan_bus(struct udevice *bus, bool recurse)
printf("No USB Device found\n");
else
printf("%d USB Device(s) found\n", priv->next_addr);
+ nbus++;
}
+#endif
+
+#if CONFIG_IS_ENABLED(COROUTINES)
+extern int udelay_yield;
+
+static void usb_scan_bus_co(void)
+{
+ usb_scan_bus((struct udevice *)co_get_arg(), true);
+ co_exit();
+}
+
+static struct co_stack *stk;
+static struct co *main_co;
+static struct co **co;
+static int co_sz = 8;
+
+static int add_usb_scan_bus_co(struct udevice *bus)
+{
+ if (!co) {
+ co = malloc(co_sz * sizeof(*co));
+ if (!co)
+ return -ENOMEM;
+ }
+ if (nbus == co_sz) {
+ struct co **nco;
+
+ co_sz *= 2;
+ nco = realloc(co, co_sz * sizeof(*co));
+ if (!nco)
+ return -ENOMEM;
+ co = nco;
+ }
+ if (!main_co) {
+ main_co = co_create(NULL, NULL, 0, NULL, NULL);
+ if (!main_co)
+ return -ENOMEM;
+ }
+ if (!stk) {
+ stk = co_stack_new(32768);
+ if (!stk)
+ return -ENOMEM;
+ }
+ co[nbus] = co_create(main_co, stk, 0, usb_scan_bus_co, bus);
+ if (!co[nbus])
+ return -ENOMEM;
+ nbus++;
+ return 0;
+}
+
+static void usb_scan_cleanup(void)
+{
+ int i;
+
+ for (i = 0; i < nbus; i++) {
+ co_destroy(co[i]);
+ co[i] = NULL;
+ }
+ nbus = 0;
+ co_destroy(main_co);
+ main_co = NULL;
+ co_stack_destroy(stk);
+ stk = NULL;
+}
+#else
+static int add_usb_scan_bus_co(struct udevice *bus)
+{
+ return 0;
+}
+
+static void usb_scan_cleanup(void)
+{
+}
+#endif
static void remove_inactive_children(struct uclass *uc, struct udevice *bus)
{
@@ -289,6 +400,7 @@ static int usb_probe_companion(struct udevice *bus)
int usb_init(void)
{
+ unsigned long t0 = timer_get_us();
int controllers_initialized = 0;
struct usb_uclass_priv *uc_priv;
struct usb_bus_priv *priv;
@@ -355,10 +467,40 @@ int usb_init(void)
continue;
priv = dev_get_uclass_priv(bus);
- if (!priv->companion)
- usb_scan_bus(bus, true);
+ if (!priv->companion) {
+ if (CONFIG_IS_ENABLED(COROUTINES)) {
+ ret = add_usb_scan_bus_co(bus);
+ if (ret)
+ goto out;
+ } else {
+ usb_scan_bus(bus, true);
+ }
+ }
}
+#if CONFIG_IS_ENABLED(COROUTINES)
+ {
+ bool done;
+ int i;
+
+ printf("Scanning %d USB bus(es)... ", nbus);
+ udelay_yield = 0xCAFEDECA;
+ do {
+ done = true;
+ for (i = 0; i < nbus; i++) {
+ if (!co[i]->done) {
+ done = false;
+ co_resume(co[i]);
+ }
+ }
+ } while (!done);
+ udelay_yield = 0;
+ printf("done\n");
+
+ usb_report_devices(uc);
+ }
+#endif
+
/*
* Now that the primary controllers have been scanned and have handed
* over any devices they do not understand to their companions, scan
@@ -388,7 +530,11 @@ int usb_init(void)
/* if we were not able to find at least one working bus, bail out */
if (controllers_initialized == 0)
printf("No USB controllers found\n");
-
+out:
+ if (nbus)
+ printf("USB: %d bus(es) scanned in %ld ms\n", nbus,
+ (timer_get_us() - t0) / 1000);
+ usb_scan_cleanup();
return usb_started ? 0 : -ENOENT;
}
--
2.43.0
