/*
* This file contains code to reset and initialize USB host controllers.
* Some of it includes work-arounds for PCI hardware and BIOS quirks.
* It may need to run early during booting -- before USB would normally
* initialize -- to ensure that Linux doesn't use any legacy modes.
*
* Copyright (c) 1999 Martin Mares <mj@ucw.cz>
* (and others)
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/acpi.h>
#include "pci-quirks.h"
#include "xhci-ext-caps.h"
#define UHCI_USBLEGSUP 0xc0 /* legacy support */
#define UHCI_USBCMD 0 /* command register */
#define UHCI_USBINTR 4 /* interrupt register */
#define UHCI_USBLEGSUP_RWC 0x8f00 /* the R/WC bits */
#define UHCI_USBLEGSUP_RO 0x5040 /* R/O and reserved bits */
#define UHCI_USBCMD_RUN 0x0001 /* RUN/STOP bit */
#define UHCI_USBCMD_HCRESET 0x0002 /* Host Controller reset */
#define UHCI_USBCMD_EGSM 0x0008 /* Global Suspend Mode */
#define UHCI_USBCMD_CONFIGURE 0x0040 /* Config Flag */
#define UHCI_USBINTR_RESUME 0x0002 /* Resume interrupt enable */
#define OHCI_CONTROL 0x04
#define OHCI_CMDSTATUS 0x08
#define OHCI_INTRSTATUS 0x0c
#define OHCI_INTRENABLE 0x10
#define OHCI_INTRDISABLE 0x14
#define OHCI_OCR (1 << 3) /* ownership change request */
#define OHCI_CTRL_RWC (1 << 9) /* remote wakeup connected */
#define OHCI_CTRL_IR (1 << 8) /* interrupt routing */
#define OHCI_INTR_OC (1 << 30) /* ownership change */
#define EHCI_HCC_PARAMS 0x08 /* extended capabilities */
#define EHCI_USBCMD 0 /* command register */
#define EHCI_USBCMD_RUN (1 << 0) /* RUN/STOP bit */
#define EHCI_USBSTS 4 /* status register */
#define EHCI_USBSTS_HALTED (1 << 12) /* HCHalted bit */
#define EHCI_USBINTR 8 /* interrupt register */
#define EHCI_CONFIGFLAG 0x40 /* configured flag register */
#define EHCI_USBLEGSUP 0 /* legacy support register */
#define EHCI_USBLEGSUP_BIOS (1 << 16) /* BIOS semaphore */
#define EHCI_USBLEGSUP_OS (1 << 24) /* OS semaphore */
#define EHCI_USBLEGCTLSTS 4 /* legacy control/status */
#define EHCI_USBLEGCTLSTS_SOOE (1 << 13) /* SMI on ownership change */
/*
* Make sure the controller is completely inactive, unable to
* generate interrupts or do DMA.
*/
void uhci_reset_hc(struct pci_dev *pdev, unsigned long base)
{
/* Turn off PIRQ enable and SMI enable. (This also turns off the
* BIOS's USB Legacy Support.) Turn off all the R/WC bits too.
*/
pci_write_config_word(pdev, UHCI_USBLEGSUP, UHCI_USBLEGSUP_RWC);
/* Reset the HC - this will force us to get a
* new notification of any already connected
* ports due to the virtual disconnect that it
* implies.
*/
outw(UHCI_USBCMD_HCRESET, base + UHCI_USBCMD);
mb();
udelay(5);
if (inw(base + UHCI_USBCMD) & UHCI_USBCMD_HCRESET)
dev_warn(&pdev->dev, "HCRESET not completed yet!\n");
/* Just to be safe, disable interrupt requests and
* make sure the controller is stopped.
*/
outw(0, base + UHCI_USBINTR);
outw(0, base + UHCI_USBCMD);
}
EXPORT_SYMBOL_GPL(uhci_reset_hc);
/*
* Initialize a controller that was newly discovered or has just been
* resumed. In either case we can't be sure of its previous state.
*
* Returns: 1 if the controller was reset, 0 otherwise.
*/
int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base)
{
u16 legsup;
unsigned int cmd, intr;
/*
* When restarting a suspended controller, we expect all the
* settings to be the same as we left them:
*
* PIRQ and SMI disabled, no R/W bits set in USBLEGSUP;
* Controller is stopped and configured with EGSM set;
* No interrupts enabled except possibly Resume Detect.
*
* If any of these conditions are violated we do a complete reset.
*/
pci_read_config_word(pdev, UHCI_USBLEGSUP, &legsup);
if (legsup & ~(UHCI_USBLEGSUP_RO | UHCI_USBLEGSUP_RWC)) {
dev_dbg(&pdev->dev, "%s: legsup = 0x%04x\n",
__func__, legsup);
goto reset_needed;
}
cmd = inw(base + UHCI_USBCMD);
if ((cmd & UHCI_USBCMD_RUN) || !(cmd & UHCI_USBCMD_CONFIGURE) ||
!(cmd & UHCI_USBCMD_EGSM)) {
dev_dbg(&pdev->dev, "%s: cmd = 0x%04x\n",
__func__, cmd);
goto reset_needed;
}
intr = inw(base + UHCI_USBINTR);
if (intr & (~UHCI_USBINTR_RESUME)) {
dev_dbg(&pdev->dev, "%s: intr = 0x%04x\n",
__func__, intr);
goto reset_needed;
}
return 0;
reset_needed:
dev_dbg(&pdev->dev, "Performing full reset\n");
uhci_reset_hc(pdev, base);
return 1;
}
EXPORT_SYMBOL_GPL(uhci_check_and_reset_hc);
static inline int io_type_enabled(struct pci_dev *pdev, unsigned int mask)
{
u16 cmd;
return !pci_read_config_word(pdev, PCI_COMMAND, &cmd) && (cmd & mask);
}
#define pio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_IO)
#define mmio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_MEMORY)
static void __devinit quirk_usb_handoff_uhci(struct pci_dev *pdev)
{
unsigned long base = 0;
int i;
if (!pio_enabled(pdev))
return;
for (i = 0; i < PCI_ROM_RESOURCE; i++)
if ((pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
base = pci_resource_start(pdev, i);
break;
}
if (base)
uhci_check_and_reset_hc(pdev, base);
}
static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
{
return pci_resource_start(pdev, idx) && mmio_enabled(pdev);
}
static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
{
void __iomem *base;
if (!mmio_resource_enabled(pdev, 0))
return;
base = pci_ioremap_bar(pdev, 0);
if (base == NULL)
return;
/* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
#ifndef __hppa__
{
u32 control = readl(base + OHCI_CONTROL);
if (control & OHCI_CTRL_IR) {
int wait_time = 500; /* arbitrary; 5 seconds */
writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
writel(OHCI_OCR, base + OHCI_CMDSTATUS);
while (wait_time > 0 &&
readl(base + OHCI_CONTROL) & OHCI_CTRL_IR) {
wait_time -= 10;
msleep(10);
}
if (wait_time <= 0)
dev_warn(&pdev->dev, "OHCI: BIOS handoff failed"
" (BIOS bug?) %08x\n",
readl(base + OHCI_CONTROL));
/* reset controller, preserving RWC */
writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
}
}
#endif
/*
* disable interrupts
*/
writel(~(u32)0, base + OHCI_INTRDISABLE);
writel(~(u32)0, base + OHCI_INTRSTATUS);
iounmap(base);
}
static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
{
int wait_time, delta;
void __iomem *base, *op_reg_base;
u32 hcc_params, val;
u8 offset, cap_length;
int count = 256/4;
int tried_handoff = 0;
if (!mmio_resource_enabled(pdev, 0))
return;
base = pci_ioremap_bar(pdev, 0);
if (base == NULL)
return;
cap_length = readb(base);
op_reg_base = base + cap_length;
/* EHCI 0.96 and later may have "extended capabilities"
* spec section 5.1 explains the bios handoff, e.g. for
* booting from USB disk or using a usb keyboard
*/
hcc_params = readl(base + EHCI_HCC_PARAMS);
offset = (hcc_params >> 8) & 0xff;
while (offset && --count) {
u32 cap;
int msec;
pci_read_config_dword(pdev, offset, &cap);
switch (cap & 0xff) {
case 1: /* BIOS/SMM/... handoff support */
if ((cap & EHCI_USBLEGSUP_BIOS)) {
dev_dbg(&pdev->dev, "EHCI: BIOS handoff\n");
#if 0
/* aleksey_gorelov@phoenix.com reports that some systems need SMI forced on,
* but that seems dubious in general (the BIOS left it off intentionally)
* and is known to prevent some systems from booting. so we won't do this
* unless maybe we can determine when we're on a system that needs SMI forced.
*/
/* BIOS workaround (?): be sure the
* pre-Linux code receives the SMI
*/
pci_read_config_dword(pdev,
offset + EHCI_USBLEGCTLSTS,
&val);
pci_write_config_dword(pdev,
offset + EHCI_USBLEGCTLSTS,
val | EHCI_USBLEGCTLSTS_SOOE);
#endif
/* some systems get upset if this semaphore is
* set for any other reason than forcing a BIOS
* handoff..
*/
pci_write_config_byte(pdev, offset + 3, 1);
}
/* if boot firmware now owns EHCI, spin till
* it hands it over.
*/
msec = 1000;
while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
tried_handoff = 1;
msleep(10);
msec -= 10;
pci_read_config_dword(pdev, offset, &cap);
}
if (cap & EHCI_USBLEGSUP_BIOS) {
/* well, possibly buggy BIOS... try to shut
* it down, and hope nothing goes too wrong
*/
dev_warn(&pdev->dev, "EHCI: BIOS handoff failed"
" (BIOS bug?) %08x\n", cap);
pci_write_config_byte(pdev, offset + 2, 0);
}
/* just in case, always disable EHCI SMIs */
pci_write_config_dword(pdev,
offset + EHCI_USBLEGCTLSTS,
0);
/* If the BIOS ever owned the controller then we
* can't expect any power sessions to remain intact.
*/
if (tried_handoff)
writel(0, op_reg_base + EHCI_CONFIGFLAG);
break;
case 0: /* illegal reserved capability */
cap = 0;
/* FALLTHROUGH */
default:
dev_warn(&pdev->dev, "EHCI: unrecognized capability "
"%02x\n", cap & 0xff);
break;
}
offset = (cap >> 8) & 0xff;
}
if (!count)
dev_printk(KERN_DEBUG, &pdev->dev, "EHCI: capability loop?\n");
/*
* halt EHCI & disable its interrupts in any case
*/
val = readl(op_reg_base + EHCI_USBSTS);
if ((val & EHCI_USBSTS_HALTED) == 0) {
val = readl(op_reg_base + EHCI_USBCMD);
val &= ~EHCI_USBCMD_RUN;
writel(val, op_reg_base + EHCI_USBCMD);
wait_time = 2000;
delta = 100;
do {
writel(0x3f, op_reg_base + EHCI_USBSTS);
udelay(delta);
wait_time -= delta;
val = readl(op_reg_base + EHCI_USBSTS);
if ((val == ~(u32)0) || (val & EHCI_USBSTS_HALTED)) {
break;
}
} while (wait_time > 0);
}
writel(0, op_reg_base + EHCI_USBINTR);
writel(0x3f, op_reg_base + EHCI_USBSTS);
iounmap(base);
return;
}
/*
* handshake - spin reading a register until handshake completes
* @ptr: address of hc register to be read
* @mask: bits to look at in result of read
* @done: value of those bits when handshake succeeds
* @wait_usec: timeout in microseconds
* @delay_usec: delay in microseconds to wait between polling
*
* Polls a register every delay_usec microseconds.
* Returns 0 when the mask bits have the value done.
* Returns -ETIMEDOUT if this condition is not true after
* wait_usec microseconds have passed.
*/
static int handshake(void __iomem *ptr, u32 mask, u32 done,
int wait_usec, int delay_usec)
{
u32 result;
do {
result = readl(ptr);
result &= mask;
if (result == done)
return 0;
udelay(delay_usec);
wait_usec -= delay_usec;
} while (wait_usec > 0);
return -ETIMEDOUT;
}
/**
* PCI Quirks for xHCI.
*
* Takes care of the handoff between the Pre-OS (i.e. BIOS) and the OS.
* It signals to the BIOS that the OS wants control of the host controller,
* and then waits 5 seconds for the BIOS to hand over control.
* If we timeout, assume the BIOS is broken and take control anyway.
*/
static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)
{
void __iomem *base;
int ext_cap_offset;
void __iomem *op_reg_base;
u32 val;
int timeout;
if (!mmio_resource_enabled(pdev, 0))
return;
base = ioremap_nocache(pci_resource_start(pdev, 0),
pci_resource_len(pdev, 0));
if (base == NULL)
return;
/*
* Find the Legacy Support Capability register -
* this is optional for xHCI host controllers.
*/
ext_cap_offset = xhci_find_next_cap_offset(base, XHCI_HCC_PARAMS_OFFSET);
do {
if (!ext_cap_offset)
/* We've reached the end of the extended capabilities */
goto hc_init;
val = readl(base + ext_cap_offset);
if (XHCI_EXT_CAPS_ID(val) == XHCI_EXT_CAPS_LEGACY)
break;
ext_cap_offset = xhci_find_next_cap_offset(base, ext_cap_offset);
} while (1);
/* If the BIOS owns the HC, signal that the OS wants it, and wait */
if (val & XHCI_HC_BIOS_OWNED) {
writel(val & XHCI_HC_OS_OWNED, base + ext_cap_offset);
/* Wait for 5 seconds with 10 microsecond polling interval */
timeout = handshake(base + ext_cap_offset, XHCI_HC_BIOS_OWNED,
0, 5000, 10);
/* Assume a buggy BIOS and take HC ownership anyway */
if (timeout) {
dev_warn(&pdev->dev, "xHCI BIOS handoff failed"
" (BIOS bug ?) %08x\n", val);
writel(val & ~XHCI_HC_BIOS_OWNED, base + ext_cap_offset);
}
}
/* Disable any BIOS SMIs */
writel(XHCI_LEGACY_DISABLE_SMI,
base + ext_cap_offset + XHCI_LEGACY_CONTROL_OFFSET);
hc_init:
op_reg_base = base + XHCI_HC_LENGTH(readl(base));
/* Wait for the host controller to be ready before writing any
* operational or runtime registers. Wait 5 seconds and no more.
*/
timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_CNR, 0,
5000, 10);
/* Assume a buggy HC and start HC initialization anyway */
if (timeout) {
val = readl(op_reg_base + XHCI_STS_OFFSET);
dev_warn(&pdev->dev,
"xHCI HW not ready after 5 sec (HC bug?) "
"status = 0x%x\n", val);
}
/* Send the halt and disable interrupts command */
val = readl(op_reg_base + XHCI_CMD_OFFSET);
val &= ~(XHCI_CMD_RUN | XHCI_IRQS);
writel(val, op_reg_base + XHCI_CMD_OFFSET);
/* Wait for the HC to halt - poll every 125 usec (one microframe). */
timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_HALT, 1,
XHCI_MAX_HALT_USEC, 125);
if (timeout) {
val = readl(op_reg_base + XHCI_STS_OFFSET);
dev_warn(&pdev->dev,
"xHCI HW did not halt within %d usec "
"status = 0x%x\n", XHCI_MAX_HALT_USEC, val);
}
iounmap(base);
}
static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
{
if (pdev->class == PCI_CLASS_SERIAL_USB_UHCI)
quirk_usb_handoff_uhci(pdev);
else if (pdev->class == PCI_CLASS_SERIAL_USB_OHCI)
quirk_usb_handoff_ohci(pdev);
else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
quirk_usb_disable_ehci(pdev);
else if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI)
quirk_usb_handoff_xhci(pdev);
}
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);
