Hi Samuel, On Tue, Apr 26, 2011 at 3:43 PM, Samuel Ortiz <sameo@xxxxxxxxxxxxxxx> wrote: > Hi Lesly, > > On Thu, Apr 14, 2011 at 05:57:54PM +0530, Lesly A M wrote: >> Workaround for TWL5030 Silicon Errata 27 & 28: >> 27 - VDD1, VDD2, may have glitches when their output value is updated. >> 28 - VDD1 and / or VDD2 DCDC clock may stop working when internal clock >> is switched from internal to external. >> >> Erratum 27: >> If the DCDC regulators is running on their internal oscillator, >> negative glitches may occur on VDD1, VDD2 output when voltage is changed. >> The OMAP device may reboot if the VDD1 or VDD2 go below the >> core minimum operating voltage. >> >> WORKAROUND >> Set up the TWL5030 DC-DC power supplies to use the HFCLKIN instead of >> the internal oscillator. >> >> Erratum 28: >> VDD1/VDD2 clock system may hang during switching the clock source from >> internal oscillator to external. VDD1/VDD2 output voltages may collapse >> if clock stops. >> >> WORKAROUND >> If HFCLK is disabled in OFFMODE, modify the sleep/wakeup sequence and >> setuptimes to make sure the switching will happen only when HFCLKIN is stable. >> Also use the TWL5030 watchdog to safeguard the first switching from >> internal oscillator to HFCLKIN during the TWL5030 init. >> >> IMPACT >> power sequence is changed. >> sleep/wakeup time values will be changed. >> >> The workaround changes are called from twl4030_power_init(), since we have to >> make some i2c_read calls to check the TWL4030 version & the i2c will not be >> initialized in the early stage. >> >> This workaround is required for TWL5030 Silicon version less than ES1.2 >> The power script & setup time changes are recommended by TI HW team. >> >> http://omapedia.org/wiki/TWL4030_power_scripts >> >> Changes taken from TWL4030 Erratum 27 workaround patch by Nishanth Menon. > This patch and the following one depend on patch#4. Please re-send it once you > agreed with Tony about where it should go. > I will make the changes for Tony's comments and repost the patches. Thanks & Regards, Lesly A M -- 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
