u-boot/common/usb_kbd.c
Thomas Watson 96991e652f console: usb: kbd: Limit poll frequency to improve performance
Using the XHCI driver, the function `usb_kbd_poll_for_event` takes
30-40ms to run. The exact time is dependent on the polling interval the
keyboard requests in its descriptor, and likely cannot be significantly
reduced without major rework to the XHCI driver.

The U-Boot EFI console service sets a timer to poll the keyboard every 5
microseconds, and this timer is checked every time a block is read off
disk. The net effect is that, on my system, loading a ~40MiB kernel and
initrd takes about 62 seconds with a slower keyboard and 53 seconds
with a faster one, with the vast majority of the time spent polling the
keyboard.

To solve this problem, this patch adds a 20ms delay between consecutive
calls to `usb_kbd_poll_for_event`. This is sufficient to reduce the
total loading time to under half a second for both keyboards, and does
not impact the perceived keystroke latency.

Signed-off-by: Thomas Watson <twatson52@icloud.com>
2022-02-11 00:03:48 +01:00

738 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2001
* Denis Peter, MPL AG Switzerland
*
* Part of this source has been derived from the Linux USB
* project.
*/
#include <common.h>
#include <console.h>
#include <dm.h>
#include <env.h>
#include <errno.h>
#include <log.h>
#include <malloc.h>
#include <memalign.h>
#include <stdio_dev.h>
#include <watchdog.h>
#include <asm/byteorder.h>
#ifdef CONFIG_SANDBOX
#include <asm/state.h>
#endif
#include <usb.h>
/*
* If overwrite_console returns 1, the stdin, stderr and stdout
* are switched to the serial port, else the settings in the
* environment are used
*/
#ifdef CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
extern int overwrite_console(void);
#else
int overwrite_console(void)
{
return 0;
}
#endif
/* Keyboard sampling rate */
#define REPEAT_RATE 40 /* 40msec -> 25cps */
#define REPEAT_DELAY 10 /* 10 x REPEAT_RATE = 400msec */
#define NUM_LOCK 0x53
#define CAPS_LOCK 0x39
#define SCROLL_LOCK 0x47
/* Modifier bits */
#define LEFT_CNTR (1 << 0)
#define LEFT_SHIFT (1 << 1)
#define LEFT_ALT (1 << 2)
#define LEFT_GUI (1 << 3)
#define RIGHT_CNTR (1 << 4)
#define RIGHT_SHIFT (1 << 5)
#define RIGHT_ALT (1 << 6)
#define RIGHT_GUI (1 << 7)
/* Size of the keyboard buffer */
#define USB_KBD_BUFFER_LEN 0x20
/* Device name */
#define DEVNAME "usbkbd"
/* Keyboard maps */
static const unsigned char usb_kbd_numkey[] = {
'1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
'\r', 0x1b, '\b', '\t', ' ', '-', '=', '[', ']',
'\\', '#', ';', '\'', '`', ',', '.', '/'
};
static const unsigned char usb_kbd_numkey_shifted[] = {
'!', '@', '#', '$', '%', '^', '&', '*', '(', ')',
'\r', 0x1b, '\b', '\t', ' ', '_', '+', '{', '}',
'|', '~', ':', '"', '~', '<', '>', '?'
};
static const unsigned char usb_kbd_num_keypad[] = {
'/', '*', '-', '+', '\r',
'1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
'.', 0, 0, 0, '='
};
static const u8 usb_special_keys[] = {
#ifdef CONFIG_USB_KEYBOARD_FN_KEYS
'2', 'H', '5', '3', 'F', '6', 'C', 'D', 'B', 'A'
#else
'C', 'D', 'B', 'A'
#endif
};
/*
* NOTE: It's important for the NUM, CAPS, SCROLL-lock bits to be in this
* order. See usb_kbd_setled() function!
*/
#define USB_KBD_NUMLOCK (1 << 0)
#define USB_KBD_CAPSLOCK (1 << 1)
#define USB_KBD_SCROLLLOCK (1 << 2)
#define USB_KBD_CTRL (1 << 3)
#define USB_KBD_LEDMASK \
(USB_KBD_NUMLOCK | USB_KBD_CAPSLOCK | USB_KBD_SCROLLLOCK)
struct usb_kbd_pdata {
unsigned long intpipe;
int intpktsize;
int intinterval;
unsigned long last_report;
struct int_queue *intq;
uint32_t repeat_delay;
uint32_t usb_in_pointer;
uint32_t usb_out_pointer;
uint8_t usb_kbd_buffer[USB_KBD_BUFFER_LEN];
uint8_t *new;
uint8_t old[USB_KBD_BOOT_REPORT_SIZE];
uint8_t flags;
};
extern int __maybe_unused net_busy_flag;
/* The period of time between two calls of usb_kbd_testc(). */
static unsigned long kbd_testc_tms;
/* Puts character in the queue and sets up the in and out pointer. */
static void usb_kbd_put_queue(struct usb_kbd_pdata *data, u8 c)
{
if (data->usb_in_pointer == USB_KBD_BUFFER_LEN - 1) {
/* Check for buffer full. */
if (data->usb_out_pointer == 0)
return;
data->usb_in_pointer = 0;
} else {
/* Check for buffer full. */
if (data->usb_in_pointer == data->usb_out_pointer - 1)
return;
data->usb_in_pointer++;
}
data->usb_kbd_buffer[data->usb_in_pointer] = c;
}
/*
* Set the LEDs. Since this is used in the irq routine, the control job is
* issued with a timeout of 0. This means, that the job is queued without
* waiting for job completion.
*/
static void usb_kbd_setled(struct usb_device *dev)
{
struct usb_interface *iface = &dev->config.if_desc[0];
struct usb_kbd_pdata *data = dev->privptr;
ALLOC_ALIGN_BUFFER(uint32_t, leds, 1, USB_DMA_MINALIGN);
*leds = data->flags & USB_KBD_LEDMASK;
usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_REPORT, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0x200, iface->desc.bInterfaceNumber, leds, 1, 0);
}
#define CAPITAL_MASK 0x20
/* Translate the scancode in ASCII */
static int usb_kbd_translate(struct usb_kbd_pdata *data, unsigned char scancode,
unsigned char modifier, int pressed)
{
uint8_t keycode = 0;
/* Key released */
if (pressed == 0) {
data->repeat_delay = 0;
return 0;
}
if (pressed == 2) {
data->repeat_delay++;
if (data->repeat_delay < REPEAT_DELAY)
return 0;
data->repeat_delay = REPEAT_DELAY;
}
/* Alphanumeric values */
if ((scancode > 3) && (scancode <= 0x1d)) {
keycode = scancode - 4 + 'a';
if (data->flags & USB_KBD_CAPSLOCK)
keycode &= ~CAPITAL_MASK;
if (modifier & (LEFT_SHIFT | RIGHT_SHIFT)) {
/* Handle CAPSLock + Shift pressed simultaneously */
if (keycode & CAPITAL_MASK)
keycode &= ~CAPITAL_MASK;
else
keycode |= CAPITAL_MASK;
}
}
if ((scancode > 0x1d) && (scancode < 0x39)) {
/* Shift pressed */
if (modifier & (LEFT_SHIFT | RIGHT_SHIFT))
keycode = usb_kbd_numkey_shifted[scancode - 0x1e];
else
keycode = usb_kbd_numkey[scancode - 0x1e];
}
/* Numeric keypad */
if ((scancode >= 0x54) && (scancode <= 0x67))
keycode = usb_kbd_num_keypad[scancode - 0x54];
if (data->flags & USB_KBD_CTRL)
keycode = scancode - 0x3;
if (pressed == 1) {
if (scancode == NUM_LOCK) {
data->flags ^= USB_KBD_NUMLOCK;
return 1;
}
if (scancode == CAPS_LOCK) {
data->flags ^= USB_KBD_CAPSLOCK;
return 1;
}
if (scancode == SCROLL_LOCK) {
data->flags ^= USB_KBD_SCROLLLOCK;
return 1;
}
}
/* Report keycode if any */
if (keycode) {
debug("%c", keycode);
usb_kbd_put_queue(data, keycode);
return 0;
}
#ifdef CONFIG_USB_KEYBOARD_FN_KEYS
if (scancode < 0x3a || scancode > 0x52 ||
scancode == 0x46 || scancode == 0x47)
return 1;
usb_kbd_put_queue(data, 0x1b);
if (scancode < 0x3e) {
/* F1 - F4 */
usb_kbd_put_queue(data, 0x4f);
usb_kbd_put_queue(data, scancode - 0x3a + 'P');
return 0;
}
usb_kbd_put_queue(data, '[');
if (scancode < 0x42) {
/* F5 - F8 */
usb_kbd_put_queue(data, '1');
if (scancode == 0x3e)
--scancode;
keycode = scancode - 0x3f + '7';
} else if (scancode < 0x49) {
/* F9 - F12 */
usb_kbd_put_queue(data, '2');
if (scancode > 0x43)
++scancode;
keycode = scancode - 0x42 + '0';
} else {
/*
* INSERT, HOME, PAGE UP, DELETE, END, PAGE DOWN,
* RIGHT, LEFT, DOWN, UP
*/
keycode = usb_special_keys[scancode - 0x49];
}
usb_kbd_put_queue(data, keycode);
if (scancode < 0x4f && scancode != 0x4a && scancode != 0x4d)
usb_kbd_put_queue(data, '~');
return 0;
#else
/* Left, Right, Up, Down */
if (scancode > 0x4e && scancode < 0x53) {
usb_kbd_put_queue(data, 0x1b);
usb_kbd_put_queue(data, '[');
usb_kbd_put_queue(data, usb_special_keys[scancode - 0x4f]);
return 0;
}
return 1;
#endif /* CONFIG_USB_KEYBOARD_FN_KEYS */
}
static uint32_t usb_kbd_service_key(struct usb_device *dev, int i, int up)
{
uint32_t res = 0;
struct usb_kbd_pdata *data = dev->privptr;
uint8_t *new;
uint8_t *old;
if (up) {
new = data->old;
old = data->new;
} else {
new = data->new;
old = data->old;
}
if ((old[i] > 3) &&
(memscan(new + 2, old[i], USB_KBD_BOOT_REPORT_SIZE - 2) ==
new + USB_KBD_BOOT_REPORT_SIZE)) {
res |= usb_kbd_translate(data, old[i], data->new[0], up);
}
return res;
}
/* Interrupt service routine */
static int usb_kbd_irq_worker(struct usb_device *dev)
{
struct usb_kbd_pdata *data = dev->privptr;
int i, res = 0;
/* No combo key pressed */
if (data->new[0] == 0x00)
data->flags &= ~USB_KBD_CTRL;
/* Left or Right Ctrl pressed */
else if ((data->new[0] == LEFT_CNTR) || (data->new[0] == RIGHT_CNTR))
data->flags |= USB_KBD_CTRL;
for (i = 2; i < USB_KBD_BOOT_REPORT_SIZE; i++) {
res |= usb_kbd_service_key(dev, i, 0);
res |= usb_kbd_service_key(dev, i, 1);
}
/* Key is still pressed */
if ((data->new[2] > 3) && (data->old[2] == data->new[2]))
res |= usb_kbd_translate(data, data->new[2], data->new[0], 2);
if (res == 1)
usb_kbd_setled(dev);
memcpy(data->old, data->new, USB_KBD_BOOT_REPORT_SIZE);
return 1;
}
/* Keyboard interrupt handler */
static int usb_kbd_irq(struct usb_device *dev)
{
if ((dev->irq_status != 0) ||
(dev->irq_act_len != USB_KBD_BOOT_REPORT_SIZE)) {
debug("USB KBD: Error %lX, len %d\n",
dev->irq_status, dev->irq_act_len);
return 1;
}
return usb_kbd_irq_worker(dev);
}
/* Interrupt polling */
static inline void usb_kbd_poll_for_event(struct usb_device *dev)
{
#if defined(CONFIG_SYS_USB_EVENT_POLL)
struct usb_kbd_pdata *data = dev->privptr;
/* Submit an interrupt transfer request */
if (usb_int_msg(dev, data->intpipe, &data->new[0],
data->intpktsize, data->intinterval, true) >= 0)
usb_kbd_irq_worker(dev);
#elif defined(CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP) || \
defined(CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE)
#if defined(CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP)
struct usb_interface *iface;
struct usb_kbd_pdata *data = dev->privptr;
iface = &dev->config.if_desc[0];
usb_get_report(dev, iface->desc.bInterfaceNumber,
1, 0, data->new, USB_KBD_BOOT_REPORT_SIZE);
if (memcmp(data->old, data->new, USB_KBD_BOOT_REPORT_SIZE)) {
usb_kbd_irq_worker(dev);
#else
struct usb_kbd_pdata *data = dev->privptr;
if (poll_int_queue(dev, data->intq)) {
usb_kbd_irq_worker(dev);
/* We've consumed all queued int packets, create new */
destroy_int_queue(dev, data->intq);
data->intq = create_int_queue(dev, data->intpipe, 1,
USB_KBD_BOOT_REPORT_SIZE, data->new,
data->intinterval);
#endif
data->last_report = get_timer(0);
/* Repeat last usb hid report every REPEAT_RATE ms for keyrepeat */
} else if (data->last_report != -1 &&
get_timer(data->last_report) > REPEAT_RATE) {
usb_kbd_irq_worker(dev);
data->last_report = get_timer(0);
}
#endif
}
/* test if a character is in the queue */
static int usb_kbd_testc(struct stdio_dev *sdev)
{
struct stdio_dev *dev;
struct usb_device *usb_kbd_dev;
struct usb_kbd_pdata *data;
/*
* Polling the keyboard for an event can take dozens of milliseconds.
* Add a delay between polls to avoid blocking activity which polls
* rapidly, like the UEFI console timer.
*/
unsigned long poll_delay = CONFIG_SYS_HZ / 50;
#ifdef CONFIG_CMD_NET
/*
* If net_busy_flag is 1, NET transfer is running,
* then we check key-pressed every second (first check may be
* less than 1 second) to improve TFTP booting performance.
*/
if (net_busy_flag)
poll_delay = CONFIG_SYS_HZ;
#endif
#ifdef CONFIG_SANDBOX
/*
* Skip delaying polls if a test requests it.
*/
if (state_get_skip_delays())
poll_delay = 0;
#endif
dev = stdio_get_by_name(sdev->name);
usb_kbd_dev = (struct usb_device *)dev->priv;
data = usb_kbd_dev->privptr;
if (get_timer(kbd_testc_tms) >= poll_delay) {
usb_kbd_poll_for_event(usb_kbd_dev);
kbd_testc_tms = get_timer(0);
}
return !(data->usb_in_pointer == data->usb_out_pointer);
}
/* gets the character from the queue */
static int usb_kbd_getc(struct stdio_dev *sdev)
{
struct stdio_dev *dev;
struct usb_device *usb_kbd_dev;
struct usb_kbd_pdata *data;
dev = stdio_get_by_name(sdev->name);
usb_kbd_dev = (struct usb_device *)dev->priv;
data = usb_kbd_dev->privptr;
while (data->usb_in_pointer == data->usb_out_pointer) {
WATCHDOG_RESET();
usb_kbd_poll_for_event(usb_kbd_dev);
}
if (data->usb_out_pointer == USB_KBD_BUFFER_LEN - 1)
data->usb_out_pointer = 0;
else
data->usb_out_pointer++;
return data->usb_kbd_buffer[data->usb_out_pointer];
}
/* probes the USB device dev for keyboard type. */
static int usb_kbd_probe_dev(struct usb_device *dev, unsigned int ifnum)
{
struct usb_interface *iface;
struct usb_endpoint_descriptor *ep;
struct usb_kbd_pdata *data;
int epNum;
if (dev->descriptor.bNumConfigurations != 1)
return 0;
iface = &dev->config.if_desc[ifnum];
if (iface->desc.bInterfaceClass != USB_CLASS_HID)
return 0;
if (iface->desc.bInterfaceSubClass != USB_SUB_HID_BOOT)
return 0;
if (iface->desc.bInterfaceProtocol != USB_PROT_HID_KEYBOARD)
return 0;
for (epNum = 0; epNum < iface->desc.bNumEndpoints; epNum++) {
ep = &iface->ep_desc[epNum];
/* Check if endpoint is interrupt IN endpoint */
if ((ep->bmAttributes & 3) != 3)
continue;
if (ep->bEndpointAddress & 0x80)
break;
}
if (epNum == iface->desc.bNumEndpoints)
return 0;
debug("USB KBD: found interrupt EP: 0x%x\n", ep->bEndpointAddress);
data = malloc(sizeof(struct usb_kbd_pdata));
if (!data) {
printf("USB KBD: Error allocating private data\n");
return 0;
}
/* Clear private data */
memset(data, 0, sizeof(struct usb_kbd_pdata));
/* allocate input buffer aligned and sized to USB DMA alignment */
data->new = memalign(USB_DMA_MINALIGN,
roundup(USB_KBD_BOOT_REPORT_SIZE, USB_DMA_MINALIGN));
/* Insert private data into USB device structure */
dev->privptr = data;
/* Set IRQ handler */
dev->irq_handle = usb_kbd_irq;
data->intpipe = usb_rcvintpipe(dev, ep->bEndpointAddress);
data->intpktsize = min(usb_maxpacket(dev, data->intpipe),
USB_KBD_BOOT_REPORT_SIZE);
data->intinterval = ep->bInterval;
data->last_report = -1;
/* We found a USB Keyboard, install it. */
debug("USB KBD: set boot protocol\n");
usb_set_protocol(dev, iface->desc.bInterfaceNumber, 0);
#if !defined(CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP) && \
!defined(CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE)
debug("USB KBD: set idle interval...\n");
usb_set_idle(dev, iface->desc.bInterfaceNumber, REPEAT_RATE / 4, 0);
#else
debug("USB KBD: set idle interval=0...\n");
usb_set_idle(dev, iface->desc.bInterfaceNumber, 0, 0);
#endif
debug("USB KBD: enable interrupt pipe...\n");
#ifdef CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE
data->intq = create_int_queue(dev, data->intpipe, 1,
USB_KBD_BOOT_REPORT_SIZE, data->new,
data->intinterval);
if (!data->intq) {
#elif defined(CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP)
if (usb_get_report(dev, iface->desc.bInterfaceNumber,
1, 0, data->new, USB_KBD_BOOT_REPORT_SIZE) < 0) {
#else
if (usb_int_msg(dev, data->intpipe, data->new, data->intpktsize,
data->intinterval, false) < 0) {
#endif
printf("Failed to get keyboard state from device %04x:%04x\n",
dev->descriptor.idVendor, dev->descriptor.idProduct);
/* Abort, we don't want to use that non-functional keyboard. */
return 0;
}
/* Success. */
return 1;
}
static int probe_usb_keyboard(struct usb_device *dev)
{
char *stdinname;
struct stdio_dev usb_kbd_dev;
int error;
/* Try probing the keyboard */
if (usb_kbd_probe_dev(dev, 0) != 1)
return -ENOENT;
/* Register the keyboard */
debug("USB KBD: register.\n");
memset(&usb_kbd_dev, 0, sizeof(struct stdio_dev));
strcpy(usb_kbd_dev.name, DEVNAME);
usb_kbd_dev.flags = DEV_FLAGS_INPUT;
usb_kbd_dev.getc = usb_kbd_getc;
usb_kbd_dev.tstc = usb_kbd_testc;
usb_kbd_dev.priv = (void *)dev;
error = stdio_register(&usb_kbd_dev);
if (error)
return error;
stdinname = env_get("stdin");
#if CONFIG_IS_ENABLED(CONSOLE_MUX)
error = iomux_doenv(stdin, stdinname);
if (error)
return error;
#else
/* Check if this is the standard input device. */
if (strcmp(stdinname, DEVNAME))
return 1;
/* Reassign the console */
if (overwrite_console())
return 1;
error = console_assign(stdin, DEVNAME);
if (error)
return error;
#endif
return 0;
}
#if !CONFIG_IS_ENABLED(DM_USB)
/* Search for keyboard and register it if found. */
int drv_usb_kbd_init(void)
{
int error, i;
debug("%s: Probing for keyboard\n", __func__);
/* Scan all USB Devices */
for (i = 0; i < USB_MAX_DEVICE; i++) {
struct usb_device *dev;
/* Get USB device. */
dev = usb_get_dev_index(i);
if (!dev)
break;
if (dev->devnum == -1)
continue;
error = probe_usb_keyboard(dev);
if (!error)
return 1;
if (error && error != -ENOENT)
return error;
}
/* No USB Keyboard found */
return -1;
}
/* Deregister the keyboard. */
int usb_kbd_deregister(int force)
{
#if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
struct stdio_dev *dev;
struct usb_device *usb_kbd_dev;
struct usb_kbd_pdata *data;
dev = stdio_get_by_name(DEVNAME);
if (dev) {
usb_kbd_dev = (struct usb_device *)dev->priv;
data = usb_kbd_dev->privptr;
#if CONFIG_IS_ENABLED(CONSOLE_MUX)
if (iomux_replace_device(stdin, DEVNAME, force ? "nulldev" : ""))
return 1;
#endif
if (stdio_deregister_dev(dev, force) != 0)
return 1;
#ifdef CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE
destroy_int_queue(usb_kbd_dev, data->intq);
#endif
free(data->new);
free(data);
}
return 0;
#else
return 1;
#endif
}
#endif
#if CONFIG_IS_ENABLED(DM_USB)
static int usb_kbd_probe(struct udevice *dev)
{
struct usb_device *udev = dev_get_parent_priv(dev);
return probe_usb_keyboard(udev);
}
static int usb_kbd_remove(struct udevice *dev)
{
struct usb_device *udev = dev_get_parent_priv(dev);
struct usb_kbd_pdata *data;
struct stdio_dev *sdev;
int ret;
sdev = stdio_get_by_name(DEVNAME);
if (!sdev) {
ret = -ENXIO;
goto err;
}
data = udev->privptr;
#if CONFIG_IS_ENABLED(CONSOLE_MUX)
if (iomux_replace_device(stdin, DEVNAME, "nulldev")) {
ret = -ENOLINK;
goto err;
}
#endif
if (stdio_deregister_dev(sdev, true)) {
ret = -EPERM;
goto err;
}
#ifdef CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE
destroy_int_queue(udev, data->intq);
#endif
free(data->new);
free(data);
return 0;
err:
printf("%s: warning, ret=%d", __func__, ret);
return ret;
}
static const struct udevice_id usb_kbd_ids[] = {
{ .compatible = "usb-keyboard" },
{ }
};
U_BOOT_DRIVER(usb_kbd) = {
.name = "usb_kbd",
.id = UCLASS_KEYBOARD,
.of_match = usb_kbd_ids,
.probe = usb_kbd_probe,
.remove = usb_kbd_remove,
};
static const struct usb_device_id kbd_id_table[] = {
{
.match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
USB_DEVICE_ID_MATCH_INT_SUBCLASS |
USB_DEVICE_ID_MATCH_INT_PROTOCOL,
.bInterfaceClass = USB_CLASS_HID,
.bInterfaceSubClass = USB_SUB_HID_BOOT,
.bInterfaceProtocol = USB_PROT_HID_KEYBOARD,
},
{ } /* Terminating entry */
};
U_BOOT_USB_DEVICE(usb_kbd, kbd_id_table);
#endif