From 8d053c79f22462f55c02c8083580730b922cf7b4 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 Aug 2009 15:39:54 -0500 Subject: [PATCH] USB: ehci-dbgp,ehci: Allow early or late use of the dbgp device If the EHCI debug port is initialized and in use, the EHCI host controller driver must follow two rules. 1) If the EHCI host driver issues a controller reset, the debug controller driver re-initialization must get called after the reset is completed. 2) The EHCI host driver should ignore any requests to the physical EHCI debug port when the EHCI debug port is in use. The code to check for the debug port was moved from ehci_pci_reinit() to ehci_pci_setup because it must get called prior to ehci_reset() which will clear the debug port registers. Signed-off-by: Jason Wessel Cc: Alan Stern Cc: dbrownell@users.sourceforge.net Cc: Ingo Molnar Cc: Andrew Morton Cc: Yinghai Lu Cc: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman --- drivers/usb/early/ehci-dbgp.c | 23 +++++++++++++++++++++ drivers/usb/host/ehci-hcd.c | 8 +++++++ drivers/usb/host/ehci-hub.c | 10 +++++++++ drivers/usb/host/ehci-pci.c | 39 +++++++++++++++++------------------ include/linux/usb/ehci_def.h | 10 +++++++++ 5 files changed, 70 insertions(+), 20 deletions(-) diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c index 06e05ea17871..b88cb65b64e0 100644 --- a/drivers/usb/early/ehci-dbgp.c +++ b/drivers/usb/early/ehci-dbgp.c @@ -933,3 +933,26 @@ struct console early_dbgp_console = { .flags = CON_PRINTBUFFER, .index = -1, }; + +int dbgp_reset_prep(void) +{ + u32 ctrl; + + dbgp_not_safe = 1; + if (!ehci_debug) + return 0; + + if (early_dbgp_console.index != -1 && + !(early_dbgp_console.flags & CON_BOOT)) + return 1; + /* This means the console is not initialized, or should get + * shutdown so as to allow for reuse of the usb device, which + * means it is time to shutdown the usb debug port. */ + ctrl = readl(&ehci_debug->control); + if (ctrl & DBGP_ENABLED) { + ctrl &= ~(DBGP_CLAIM); + writel(ctrl, &ehci_debug->control); + } + return 0; +} +EXPORT_SYMBOL_GPL(dbgp_reset_prep); diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 4f89d7ffd53a..9835e0713943 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -240,6 +240,11 @@ static int ehci_reset (struct ehci_hcd *ehci) int retval; u32 command = ehci_readl(ehci, &ehci->regs->command); + /* If the EHCI debug controller is active, special care must be + * taken before and after a host controller reset */ + if (ehci->debug && !dbgp_reset_prep()) + ehci->debug = NULL; + command |= CMD_RESET; dbg_cmd (ehci, "reset", command); ehci_writel(ehci, command, &ehci->regs->command); @@ -260,6 +265,9 @@ static int ehci_reset (struct ehci_hcd *ehci) if (ehci_is_TDI(ehci)) tdi_reset (ehci); + if (ehci->debug) + dbgp_external_startup(); + return retval; } diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index 818647c33da8..6b5e4d18d4bf 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -855,6 +855,15 @@ static int ehci_hub_control ( case SetPortFeature: selector = wIndex >> 8; wIndex &= 0xff; + if (unlikely(ehci->debug)) { + /* If the debug port is active any port + * feature requests should get denied */ + if (wIndex == HCS_DEBUG_PORT(ehci->hcs_params) && + (readl(&ehci->debug->control) & DBGP_ENABLED)) { + retval = -ENODEV; + goto error_exit; + } + } if (!wIndex || wIndex > ports) goto error; wIndex--; @@ -951,6 +960,7 @@ static int ehci_hub_control ( /* "stall" on error */ retval = -EPIPE; } +error_exit: spin_unlock_irqrestore (&ehci->lock, flags); return retval; } diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c index a88ad517ec5c..378861b9d79a 100644 --- a/drivers/usb/host/ehci-pci.c +++ b/drivers/usb/host/ehci-pci.c @@ -27,28 +27,8 @@ /* called after powerup, by probe or system-pm "wakeup" */ static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev) { - u32 temp; int retval; - /* optional debug port, normally in the first BAR */ - temp = pci_find_capability(pdev, 0x0a); - if (temp) { - pci_read_config_dword(pdev, temp, &temp); - temp >>= 16; - if ((temp & (3 << 13)) == (1 << 13)) { - temp &= 0x1fff; - ehci->debug = ehci_to_hcd(ehci)->regs + temp; - temp = ehci_readl(ehci, &ehci->debug->control); - ehci_info(ehci, "debug port %d%s\n", - HCS_DEBUG_PORT(ehci->hcs_params), - (temp & DBGP_ENABLED) - ? " IN USE" - : ""); - if (!(temp & DBGP_ENABLED)) - ehci->debug = NULL; - } - } - /* we expect static quirk code to handle the "extended capabilities" * (currently just BIOS handoff) allowed starting with EHCI 0.96 */ @@ -195,6 +175,25 @@ static int ehci_pci_setup(struct usb_hcd *hcd) break; } + /* optional debug port, normally in the first BAR */ + temp = pci_find_capability(pdev, 0x0a); + if (temp) { + pci_read_config_dword(pdev, temp, &temp); + temp >>= 16; + if ((temp & (3 << 13)) == (1 << 13)) { + temp &= 0x1fff; + ehci->debug = ehci_to_hcd(ehci)->regs + temp; + temp = ehci_readl(ehci, &ehci->debug->control); + ehci_info(ehci, "debug port %d%s\n", + HCS_DEBUG_PORT(ehci->hcs_params), + (temp & DBGP_ENABLED) + ? " IN USE" + : ""); + if (!(temp & DBGP_ENABLED)) + ehci->debug = NULL; + } + } + ehci_reset(ehci); /* at least the Genesys GL880S needs fixup here */ diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h index 07851e05d763..1909d924f816 100644 --- a/include/linux/usb/ehci_def.h +++ b/include/linux/usb/ehci_def.h @@ -179,6 +179,16 @@ extern struct console early_dbgp_console; #ifdef CONFIG_EARLY_PRINTK_DBGP /* Call backs from ehci host driver to ehci debug driver */ extern int dbgp_external_startup(void); +extern int dbgp_reset_prep(void); +#else +static inline int dbgp_reset_prep(void) +{ + return 1; +} +static inline int dbgp_external_startup(void) +{ + return -1; +} #endif #endif /* __LINUX_USB_EHCI_DEF_H */ -- GitLab