USB: EHCI: Add alias for Broadcom INSNREG

Refactor struct ehci_regs to avoid accessing beyond the end of
port_status. This change results in no difference in the final
object code.

Avoids several warnings when building with -Warray-bounds:

drivers/usb/host/ehci-brcm.c: In function 'ehci_brcm_reset':
drivers/usb/host/ehci-brcm.c:113:32: warning: array subscript 16 is above array bounds of 'u32[15]' {aka 'unsigned int[15]'} [-Warray-bounds]
  113 |  ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]);
      |                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/usb/host/ehci.h:274,
                 from drivers/usb/host/ehci-brcm.c:15:
./include/linux/usb/ehci_def.h:132:7: note: while referencing 'port_status'
  132 |   u32 port_status[HCS_N_PORTS_MAX];
      |       ^~~~~~~~~~~

Note that the documentation around this proprietary register was
confusing. If "USB_EHCI_INSNREG00" is at port_status[0x0f], its offset
would be 0x80 (not 0x90). The comments have been adjusted to fix this
apparent typo.

Fixes: 9df231511b ("usb: ehci: Add new EHCI driver for Broadcom STB SoC's")
Cc: Al Cooper <alcooperx@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: bcm-kernel-feedback-list@broadcom.com
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210818173018.2259231-3-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kees Cook 2021-08-18 10:30:18 -07:00 committed by Greg Kroah-Hartman
parent 72dd184323
commit e4788edc73
2 changed files with 14 additions and 10 deletions

View File

@ -108,10 +108,9 @@ static int ehci_brcm_reset(struct usb_hcd *hcd)
/*
* SWLINUX-1705: Avoid OUT packet underflows during high memory
* bus usage
* port_status[0x0f] = Broadcom-proprietary USB_EHCI_INSNREG00 @ 0x90
*/
ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]);
ehci_writel(ehci, 0x00000001, &ehci->regs->port_status[0x12]);
ehci_writel(ehci, 0x00800040, &ehci->regs->brcm_insnreg[1]);
ehci_writel(ehci, 0x00000001, &ehci->regs->brcm_insnreg[3]);
return ehci_setup(hcd);
}
@ -223,11 +222,9 @@ static int __maybe_unused ehci_brcm_resume(struct device *dev)
/*
* SWLINUX-1705: Avoid OUT packet underflows during high memory
* bus usage
* port_status[0x0f] = Broadcom-proprietary USB_EHCI_INSNREG00
* @ 0x90
*/
ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]);
ehci_writel(ehci, 0x00000001, &ehci->regs->port_status[0x12]);
ehci_writel(ehci, 0x00800040, &ehci->regs->brcm_insnreg[1]);
ehci_writel(ehci, 0x00000001, &ehci->regs->brcm_insnreg[3]);
ehci_resume(hcd, false);

View File

@ -176,16 +176,23 @@ struct ehci_regs {
#define USBMODE_CM_HC (3<<0) /* host controller mode */
#define USBMODE_CM_IDLE (0<<0) /* idle state */
};
u32 reserved4;
/* Moorestown has some non-standard registers, partially due to the fact that
* its EHCI controller has both TT and LPM support. HOSTPCx are extensions to
* PORTSCx
*/
/* HOSTPC: offset 0x84 */
u32 hostpc[HCS_N_PORTS_MAX];
union {
struct {
u32 reserved4;
/* HOSTPC: offset 0x84 */
u32 hostpc[HCS_N_PORTS_MAX];
#define HOSTPC_PHCD (1<<22) /* Phy clock disable */
#define HOSTPC_PSPD (3<<25) /* Port speed detection */
};
/* Broadcom-proprietary USB_EHCI_INSNREG00 @ 0x80 */
u32 brcm_insnreg[4];
};
u32 reserved5[2];