Michael, On 12/02/2013 11:51 AM, Michael Trimarchi wrote: > Hi Roger > > On Mon, Dec 2, 2013 at 10:39 AM, Roger Quadros <rogerq@xxxxxx> wrote: >> +Benoit, Tony, Paul. >> >> Hi Michael, >> >> On 11/30/2013 06:48 AM, Michael Trimarchi wrote: >>> Hi Roger >>> >>> On Fri, Nov 29, 2013 at 2:01 PM, Roger Quadros <rogerq@xxxxxx> wrote: >>>> With u-boot 2013.10, USB devices are sometimes not detected >>>> on OMAP4 Panda. To make us independent of what bootloader does >>>> with the USB Host module, we must RESET it to get it to a known >>>> good state. This patch Soft RESETs the USB Host module. >>>> >>>> Reported-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx> >>>> Cc: <stable@xxxxxxxxxxxxxxx> # 3.10+ >>>> Signed-off-by: Roger Quadros <rogerq@xxxxxx> >>>> --- >>>> drivers/mfd/omap-usb-host.c | 115 +++++++++++++++++++++++++++++++++++++++++--- >>>> 1 file changed, 109 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/drivers/mfd/omap-usb-host.c b/drivers/mfd/omap-usb-host.c >>>> index 142650f..d4bd464 100644 >>>> --- a/drivers/mfd/omap-usb-host.c >>>> +++ b/drivers/mfd/omap-usb-host.c >>>> @@ -43,14 +43,18 @@ >>>> /* UHH Register Set */ >>>> #define OMAP_UHH_REVISION (0x00) >>>> #define OMAP_UHH_SYSCONFIG (0x10) >>>> -#define OMAP_UHH_SYSCONFIG_MIDLEMODE (1 << 12) >>>> +#define OMAP_UHH_SYSCONFIG_MIDLEMASK (3 << 12) >>>> +#define OMAP_UHH_SYSCONFIG_MIDLESHIFT (12) >>>> #define OMAP_UHH_SYSCONFIG_CACTIVITY (1 << 8) >>>> -#define OMAP_UHH_SYSCONFIG_SIDLEMODE (1 << 3) >>>> +#define OMAP_UHH_SYSCONFIG_SIDLEMASK (3 << 3) >>>> +#define OMAP_UHH_SYSCONFIG_SIDLESHIFT (3) >>>> #define OMAP_UHH_SYSCONFIG_ENAWAKEUP (1 << 2) >>>> #define OMAP_UHH_SYSCONFIG_SOFTRESET (1 << 1) >>>> #define OMAP_UHH_SYSCONFIG_AUTOIDLE (1 << 0) >>>> >>>> #define OMAP_UHH_SYSSTATUS (0x14) >>>> +#define OMAP_UHH_SYSSTATUS_RESETDONE (1 << 0) >>>> + >>>> #define OMAP_UHH_HOSTCONFIG (0x40) >>>> #define OMAP_UHH_HOSTCONFIG_ULPI_BYPASS (1 << 0) >>>> #define OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS (1 << 0) >>>> @@ -66,10 +70,10 @@ >>>> #define OMAP4_UHH_HOSTCONFIG_APP_START_CLK (1 << 31) >>>> >>>> /* OMAP4-specific defines */ >>>> -#define OMAP4_UHH_SYSCONFIG_IDLEMODE_CLEAR (3 << 2) >>>> -#define OMAP4_UHH_SYSCONFIG_NOIDLE (1 << 2) >>>> -#define OMAP4_UHH_SYSCONFIG_STDBYMODE_CLEAR (3 << 4) >>>> -#define OMAP4_UHH_SYSCONFIG_NOSTDBY (1 << 4) >>>> +#define OMAP4_UHH_SYSCONFIG_MIDLEMASK (3 << 2) >>>> +#define OMAP4_UHH_SYSCONFIG_MIDLESHIFT (2) >>>> +#define OMAP4_UHH_SYSCONFIG_SIDLEMASK (3 << 4) >>>> +#define OMAP4_UHH_SYSCONFIG_SIDLESHIFT (4) >>>> #define OMAP4_UHH_SYSCONFIG_SOFTRESET (1 << 0) >>>> >>>> #define OMAP4_P1_MODE_CLEAR (3 << 16) >>>> @@ -81,6 +85,12 @@ >>>> >>>> #define OMAP_UHH_DEBUG_CSR (0x44) >>>> >>>> +/* MIDLE modes */ >>>> +#define OMAP_UHH_SYSCONFIG_MIDLE_NOSTANDBY (1) >>>> + >>>> +/* SIDLE modes */ >>>> +#define OMAP_UHH_SYSCONFIG_SIDLE_NOIDLE (1) >>>> + >>>> /* Values of UHH_REVISION - Note: these are not given in the TRM */ >>>> #define OMAP_USBHS_REV1 0x00000010 /* OMAP3 */ >>>> #define OMAP_USBHS_REV2 0x50700100 /* OMAP4 */ >>>> @@ -474,6 +484,97 @@ static unsigned omap_usbhs_rev2_hostconfig(struct usbhs_hcd_omap *omap, >>>> return reg; >>>> } >>>> >>> >>> I'm digging in the code but as I understand this should be done by >>> omap_hwmod and >>> i660 avoid reset of the ehci module. This is done by ocp_softreset? >>> >> >> It won't be done by omap_hwmod as we set HWMOD_INIT_NO_RESET flag in the hwmod data [1]. >> >> Question is do we do it in the driver of leave it to hwmod? >> >> The other concern about i660 is in this comment [1] >> > > I don't find any description of this errata for omap4. Is this errata valid? I can't say for sure. You might have to try it out without those flags and see if it works reliably. > > My change was to remove the NO_INIT and add 2uS as you have done The 2uS delay that I added was my mistake and I don't think it is required. Just removing HWMOD_INIT_NO_RESET should work. cheers, -roger > >> /* >> * During system oot; If the hwmod framework resets the module >> * the module will have smart idle settings; which can lead to deadlock >> * (above Errata Id:i660); so, dont reset the module during boot; >> * Use HWMOD_INIT_NO_RESET. >> */ >> >> But if you look at the errata document [2], Advisory 1.108, it doesn't say that we can't be in smart-idle, but >> only that we should put the module in force-idle, before cutting the module's functional clock. It also states >> that the only way to recover from a lockup condition is to soft reset the module. So I'm not sure if the above comment >> in the code is really valid. What if the lockup happens in the bootloader? In that case we will have to reset the module in >> the kernel. > > Michael > >> >> Doing the reset in probe does solve a problem for now i.e. eliminates dependency on bootloader. >> >> [1] - http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c#n2024 >> [2] - http://www.ti.com/litv/pdf/sprz318e >> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html