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? My change was to remove the NO_INIT and add 2uS as you have done > /* > * 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 > >> >>> +static void omap_usbhs_rev1_reset(struct device *dev) >>> +{ >>> + struct usbhs_hcd_omap *omap = dev_get_drvdata(dev); >>> + u32 reg; >>> + unsigned long timeout; >>> + >>> + reg = usbhs_read(omap->uhh_base, OMAP_UHH_SYSCONFIG); >>> + >>> + /* Soft Reset */ >>> + usbhs_write(omap->uhh_base, OMAP_UHH_SYSCONFIG, >>> + reg | OMAP_UHH_SYSCONFIG_SOFTRESET); >>> + >>> + timeout = jiffies + msecs_to_jiffies(100); >>> + while (!(usbhs_read(omap->uhh_base, OMAP_UHH_SYSSTATUS) >>> + & OMAP_UHH_SYSSTATUS_RESETDONE)) { >>> + cpu_relax(); >>> + >>> + if (time_after(jiffies, timeout)) { >>> + dev_err(dev, "Soft RESET operation timed out\n"); >>> + break; >>> + } >>> + } >>> + >>> + /* Set No-Standby */ >>> + reg &= ~OMAP_UHH_SYSCONFIG_MIDLEMASK; >>> + reg |= OMAP_UHH_SYSCONFIG_MIDLE_NOSTANDBY >>> + << OMAP_UHH_SYSCONFIG_MIDLESHIFT; >>> + >>> + /* Set No-Idle */ >>> + reg &= ~OMAP_UHH_SYSCONFIG_SIDLEMASK; >>> + reg |= OMAP_UHH_SYSCONFIG_SIDLE_NOIDLE >>> + << OMAP_UHH_SYSCONFIG_SIDLESHIFT; >>> + >>> + usbhs_write(omap->uhh_base, OMAP_UHH_SYSCONFIG, reg); >>> +} >>> + >>> +static void omap_usbhs_rev2_reset(struct device *dev) >>> +{ >>> + struct usbhs_hcd_omap *omap = dev_get_drvdata(dev); >>> + u32 reg; >>> + unsigned long timeout; >>> + >>> + reg = usbhs_read(omap->uhh_base, OMAP_UHH_SYSCONFIG); >>> + >>> + /* Soft Reset */ >>> + usbhs_write(omap->uhh_base, OMAP_UHH_SYSCONFIG, >>> + reg | OMAP4_UHH_SYSCONFIG_SOFTRESET); >>> + >>> + /* OMAP4: Need to wait before SYSCONFIG can be accessed */ >>> + udelay(2); >> >> is this the srst_udelay? > > It was supposed to be, but it doesn't seem to be necessary for the UHH module. So I'll get rid of that. > Ok > cheers, > -roger > Michael -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
