libpayload/uhci: Re-write UHCI RH driver w/ generic_hub API

This is a complete rewrite of the UHCI root-hub driver, based on
the xHCI one. We are doing things by the book as far as possible.
One special case is uhci_rh_reset_port() which does the reset se-
quencing that usually the hardware would do.

This abandons some quirks of the old driver:
* Ports are not disabled/re-enabled for every attachment anymore.
* We solely rely on the Connect Status Change bit to track changes.
* Further status changes are now deferred to the next polling round.

The latter fixes endless loops in combination with commit 7faff543da
(libpayload: usb: Detach unused USB devices).

Change-Id: I5211728775eb94dfc23fa82ebf00fe5c99039709
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75504
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
This commit is contained in:
Nico Huber 2023-05-19 20:19:56 +00:00 committed by Felix Held
parent 4c0dc4ee91
commit edcde0ba7a
1 changed files with 96 additions and 157 deletions

View File

@ -1,6 +1,6 @@
/*
*
* Copyright (C) 2008-2010 coresystems GmbH
* Copyright (C) 2013 secunet Security Networks AG
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@ -28,184 +28,123 @@
//#define USB_DEBUG
#include <libpayload.h>
#include "uhci.h"
#include <stdint.h>
#include <stdbool.h>
#include <usb/usb.h>
#include "generic_hub.h"
#include "uhci_private.h"
#include "uhci.h"
typedef struct {
int port[2];
} rh_inst_t;
#define PORTSC(p) (PORTSC1 + ((p) - 1) * sizeof(uint16_t))
#define PORTSC_CCS (1 << 0)
#define PORTSC_CSC (1 << 1)
#define PORTSC_PED (1 << 2)
#define PORTSC_PEDC (1 << 3)
#define PORTSC_LSDA (1 << 8)
#define PORTSC_PR (1 << 9)
#define PORTSC_SUSP (1 << 12)
#define PORTSC_SC_BITS (PORTSC_CSC | PORTSC_PEDC)
#define RH_INST(dev) ((rh_inst_t*)(dev)->data)
static void
uhci_rh_enable_port(usbdev_t *dev, int port)
static int
uhci_rh_port_status_changed(usbdev_t *const dev, const int port)
{
u16 value;
hci_t *controller = dev->controller;
if (port == 1)
port = PORTSC1;
else if (port == 2)
port = PORTSC2;
else {
usb_debug("Invalid port %d\n", port);
return;
}
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port));
const bool changed = portsc & (PORTSC_CSC | PORTSC_PEDC);
uhci_reg_write16(controller, port,
uhci_reg_read16(controller, port) & ~(1 << 12)); /* wakeup */
/* always clear all the status change bits */
uhci_reg_write16(dev->controller, PORTSC(port), portsc);
uhci_reg_write16(controller, port,
uhci_reg_read16(controller, port) | 1 << 9); /* reset */
mdelay(30); // >10ms
uhci_reg_write16(controller, port,
uhci_reg_read16(controller, port) & ~(1 << 9));
mdelay(1); // >5.3us per spec, <3ms because some devices make trouble
uhci_reg_write16(controller, port,
uhci_reg_read16(controller, port) | 1 << 2); /* enable */
/* wait for controller to enable port */
/* TOTEST: how long to wait? 100ms for now */
int timeout = 200; /* time out after 200 * 500us == 100ms */
do {
value = uhci_reg_read16(controller, port);
udelay(500); timeout--;
} while (((value & (1 << 2)) == 0) && (value & 0x01) && timeout);
if (!timeout)
usb_debug("Warning: uhci_rh: port enabling timed out.\n");
}
/* disable root hub */
static void
uhci_rh_disable_port(usbdev_t *dev, int port)
{
hci_t *controller = dev->controller;
if (port == 1)
port = PORTSC1;
else if (port == 2)
port = PORTSC2;
else {
usb_debug("Invalid port %d\n", port);
return;
}
uhci_reg_write16(controller, port,
uhci_reg_read16(controller, port) & ~4);
u16 value;
/* wait for controller to disable port */
/* TOTEST: how long to wait? 100ms for now */
int timeout = 200; /* time out after 200 * 500us == 100ms */
do {
value = uhci_reg_read16(controller, port);
udelay(500); timeout--;
} while (((value & (1 << 2)) != 0) && timeout);
if (!timeout)
usb_debug("Warning: uhci_rh: port disabling timed out.\n");
}
static void
uhci_rh_scanport(usbdev_t *dev, int port)
{
int portsc, offset;
if (port == 1) {
portsc = PORTSC1;
offset = 0;
} else if (port == 2) {
portsc = PORTSC2;
offset = 1;
} else {
usb_debug("Invalid port %d\n", port);
return;
}
int devno = RH_INST(dev)->port[offset];
if ((devno != -1) && (dev->controller->devices[devno] != 0)) {
usb_detach_device(dev->controller, devno);
RH_INST(dev)->port[offset] = -1;
}
uhci_reg_write16(dev->controller, portsc,
uhci_reg_read16(dev->controller, portsc) | (1 << 3) | (1 << 2)); // clear port state change, enable port
mdelay(100); // wait for signal to stabilize
if ((uhci_reg_read16(dev->controller, portsc) & 1) != 0) {
// device attached
uhci_rh_disable_port(dev, port);
uhci_rh_enable_port(dev, port);
usb_speed speed = ((uhci_reg_read16(dev->controller, portsc) >> 8) & 1);
RH_INST(dev)->port[offset] = usb_attach_device(dev->controller, dev->address, portsc, speed);
}
return changed;
}
static int
uhci_rh_report_port_changes(usbdev_t *dev)
uhci_rh_port_connected(usbdev_t *const dev, const int port)
{
u16 stored, real;
stored = (RH_INST(dev)->port[0] == -1);
real = ((uhci_reg_read16(dev->controller, PORTSC1) & 1) == 0);
if (stored != real) {
usb_debug("change on port 1\n");
return 1;
}
stored = (RH_INST(dev)->port[1] == -1);
real = ((uhci_reg_read16(dev->controller, PORTSC2) & 1) == 0);
if (stored != real) {
usb_debug("change on port 2\n");
return 2;
}
// maybe detach+attach happened between two scans?
if ((uhci_reg_read16(dev->controller, PORTSC1) & 2) > 0) {
usb_debug("possibly re-attached on port 1\n");
return 1;
}
if ((uhci_reg_read16(dev->controller, PORTSC2) & 2) > 0) {
usb_debug("possibly re-attached on port 2\n");
return 2;
}
// no change
return -1;
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port));
return !!(portsc & PORTSC_CCS);
}
static void
uhci_rh_destroy(usbdev_t *dev)
static int
uhci_rh_port_enabled(usbdev_t *const dev, const int port)
{
usb_detach_device(dev->controller, 1);
usb_detach_device(dev->controller, 2);
uhci_rh_disable_port(dev, 1);
uhci_rh_disable_port(dev, 2);
free(RH_INST(dev));
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port));
return !(portsc & PORTSC_SUSP) && (portsc & PORTSC_PED);
}
static void
uhci_rh_poll(usbdev_t *dev)
static usb_speed
uhci_rh_port_speed(usbdev_t *const dev, const int port)
{
int port;
while ((port = uhci_rh_report_port_changes(dev)) != -1)
uhci_rh_scanport(dev, port);
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port));
const bool low_speed = portsc & PORTSC_LSDA;
return low_speed ? LOW_SPEED : FULL_SPEED;
}
static int
uhci_rh_enable_port(usbdev_t *const dev, const int port)
{
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port)) & ~PORTSC_SUSP;
uhci_reg_write16(dev->controller, PORTSC(port), portsc & ~(PORTSC_SC_BITS | PORTSC_SUSP));
uhci_reg_write16(dev->controller, PORTSC(port), (portsc & ~PORTSC_SC_BITS) | PORTSC_PED);
return 0;
}
static int
uhci_rh_disable_port(usbdev_t *const dev, const int port)
{
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port));
uhci_reg_write16(dev->controller, PORTSC(port), portsc & ~(PORTSC_SC_BITS | PORTSC_PED));
return 0;
}
static int
uhci_rh_reset_port(usbdev_t *const dev, const int port)
{
const u16 portsc = uhci_reg_read16(dev->controller, PORTSC(port)) & ~PORTSC_PR;
/* Trigger port reset. */
uhci_reg_write16(dev->controller, PORTSC(port), portsc | PORTSC_PR);
/* Wait for 15ms (usb20 spec 11.5.1.5: reset should take 10 to 20ms). */
mdelay(15);
/* Clear port reset. */
uhci_reg_write16(dev->controller, PORTSC(port), portsc & ~PORTSC_PR);
udelay(10); /* Linux waits this long. */
/* Enable port. */
uhci_reg_write16(dev->controller, PORTSC(port), portsc | PORTSC_PED);
/* Clear status-change bits one last time. */
uhci_reg_write16(dev->controller, PORTSC(port), portsc | PORTSC_PED | PORTSC_SC_BITS);
return 0;
}
static const generic_hub_ops_t uhci_rh_ops = {
.hub_status_changed = NULL,
.port_status_changed = uhci_rh_port_status_changed,
.port_connected = uhci_rh_port_connected,
.port_in_reset = NULL,
.port_enabled = uhci_rh_port_enabled,
.port_speed = uhci_rh_port_speed,
.enable_port = uhci_rh_enable_port,
.disable_port = uhci_rh_disable_port,
.start_port_reset = NULL,
.reset_port = uhci_rh_reset_port,
};
void
uhci_rh_init(usbdev_t *dev)
{
dev->destroy = uhci_rh_destroy;
dev->poll = uhci_rh_poll;
uhci_rh_enable_port(dev, 1);
uhci_rh_enable_port(dev, 2);
dev->data = xmalloc(sizeof(rh_inst_t));
RH_INST(dev)->port[0] = -1;
RH_INST(dev)->port[1] = -1;
/* we can set them here because a root hub _really_ shouldn't
appear elsewhere */
/* we can set them here because a root hub _really_ shouldn't appear elsewhere */
dev->address = 0;
dev->hub = -1;
dev->port = -1;
generic_hub_init(dev, 2, &uhci_rh_ops);
usb_debug("UHCI: root hub init done\n");
}