From e4788edc730a0d2b26e1ae1f08fbb3f635b92dbb Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 18 Aug 2021 10:30:18 -0700 Subject: [PATCH] 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: 9df231511bd6 ("usb: ehci: Add new EHCI driver for Broadcom STB SoC's") Cc: Al Cooper Cc: Alan Stern Cc: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org Cc: bcm-kernel-feedback-list@broadcom.com Suggested-by: Arnd Bergmann Acked-by: Alan Stern Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20210818173018.2259231-3-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-brcm.c | 11 ++++------- include/linux/usb/ehci_def.h | 13 ++++++++++--- 2 files changed, 14 insertions(+), 10 deletions(-) diff --git a/drivers/usb/host/ehci-brcm.c b/drivers/usb/host/ehci-brcm.c index 3e0ebe8cc649..d3626bfa966b 100644 --- a/drivers/usb/host/ehci-brcm.c +++ b/drivers/usb/host/ehci-brcm.c @@ -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); diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h index dcbe2b068569..c892c5bc6638 100644 --- a/include/linux/usb/ehci_def.h +++ b/include/linux/usb/ehci_def.h @@ -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]; -- 2.11.0