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authorThierry Reding <treding@nvidia.com>2015-09-08 09:38:03 (GMT)
committerTom Warren <twarren@nvidia.com>2015-09-16 23:11:31 (GMT)
commitaba11d4476b56eb7712184597eb303ae544f0c69 (patch)
treee9b32cefb1b3a59f06b14fd3b522997dc3bf8ee9 /arch/arm/mach-tegra/tegra124/clock.c
parent20613c9231d53720b35ebe8ae67a9d4cf70a3620 (diff)
downloadu-boot-aba11d4476b56eb7712184597eb303ae544f0c69.tar.xz
ARM: tegra124: Clear IDDQ when enabling PLLC
Enabling a PLL while IDDQ is high. The Linux kernel checks for this condition and warns about it verbosely, so while this seems to work fine, fix it up according to the programming guidelines provided in the Tegra K1 TRM (v02p), Section 5.3.8.1 ("PLLC and PLLC4 Startup Sequence"). Reported-by: Nicolas Chauvet <kwizart@gmail.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Tom Warren <twarren@nvidia.com>
Diffstat (limited to 'arch/arm/mach-tegra/tegra124/clock.c')
-rw-r--r--arch/arm/mach-tegra/tegra124/clock.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/tegra124/clock.c b/arch/arm/mach-tegra/tegra124/clock.c
index aa046e8..1e71146 100644
--- a/arch/arm/mach-tegra/tegra124/clock.c
+++ b/arch/arm/mach-tegra/tegra124/clock.c
@@ -809,6 +809,11 @@ void clock_early_init(void)
tegra30_set_up_pllp();
+ /* clear IDDQ before accessing any other PLLC registers */
+ pllinfo = &tegra_pll_info_table[CLOCK_ID_CGENERAL];
+ clrbits_le32(&clkrst->crc_pll[CLOCK_ID_CGENERAL].pll_misc, PLLC_IDDQ);
+ udelay(2);
+
/*
* PLLC output frequency set to 600Mhz
* PLLD output frequency set to 925Mhz