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Description of DRA7 Errata i932: In rare circumstances DPLL_VIDEO1 and DPLL_VIDEO2 PLL's may not lock on the first attempt during DSS initialization. When this occurs, a subsequent attempt to relock the PLL will result in PLL successfully locking. This patch does the following as per the errata recommendation: - retries locking the PLL upto 20 times. - The time to wait for a PLL lock set to 1000 REFCLK cycles. We use usleep_range to wait for 1000 REFCLK cycles in the us range. This tight constraint is imposed as a lock later than 1000 REFCLK cycles may have high jitter. - Criteria for PLL lock is extended from check on just the PLL_LOCK bit to check on 6 PLL_STATUS bits. Silicon Versions Impacted: DRA71, DRA72, DRA74, DRA76 - All silicon revisions AM57x - All silicon revisions OMAP4/5 are not impacted by this errata Signed-off-by: Venkateswara Rao Mandela <venkat.mandela@ti.com> [tomi.valkeinen@ti.com: ported to v4.14] Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Linux kernel
============
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