clk: tegra: Fix warning caused by pll_u failing to lock
If the pll_u is not configured by the bootloader, then on kernel boot the following warning is seen: clk_pll_wait_for_lock: Timed out waiting for pll pll_u_vco lock tegra_init_from_table: Failed to enable pll_u_out1 ------------[ cut here ]------------ WARNING: at drivers/clk/tegra/clk.c:269 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-rc4-next-20151214+ #1 Hardware name: NVIDIA Tegra210 P2371 reference board (E.1) (DT) task: ffffffc0bc0a0000 ti: ffffffc0bc0a8000 task.ti: ffffffc0bc0a8000 PC is at tegra_init_from_table+0x140/0x164 LR is at tegra_init_from_table+0x140/0x164 pc : [<ffffffc0008fee78>] lr : [<ffffffc0008fee78>] pstate: 80000045 sp : ffffffc0bc0abd50 x29: ffffffc0bc0abd50 x28: ffffffc00090b8a8 x27: ffffffc000a06000 x26: ffffffc0bc019780 x25: ffffffc00086a708 x24: ffffffc00086a790 x23: ffffffc0006d7188 x22: ffffffc0bc010000 x21: 000000000000016e x20: ffffffc0bc00d100 x19: ffffffc000944178 x18: 0000000000000007 x17: 000000000000000e x16: 0000000000000001 x15: 0000000000000007 x14: 000000000000000e x13: 0000000000000013 x12: 000000000000001a x11: 000000000000004d x10: 0000000000000750 x9 : ffffffc0bc0a8000 x8 : ffffffc0bc0a07b0 x7 : 0000000000000001 x6 : 0000000002d5f0f8 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000002 x2 : ffffffc000996724 x1 : 0000000000000000 x0 : 0000000000000032 ---[ end trace cbd20ae519e92ced ]--- Call trace: [<ffffffc0008fee78>] tegra_init_from_table+0x140/0x164 [<ffffffc000900ac8>] tegra210_clock_apply_init_table+0x20/0x28 [<ffffffc0008fec40>] tegra_clocks_apply_init_table+0x18/0x24 [<ffffffc00008291c>] do_one_initcall+0x90/0x194 [<ffffffc0008cfab0>] kernel_init_freeable+0x148/0x1e8 [<ffffffc000636bb0>] kernel_init+0x10/0xdc [<ffffffc000085cd0>] ret_from_fork+0x10/0x40 clk_pll_wait_for_lock: Timed out waiting for pll pll_u_vco lock tegra_init_from_table: Failed to enable pll_u_out2 ------------[ cut here ]------------ pll_u can be either controlled by software or hardware and this is selected via the OVERRIDE bit in the pll_u base register. In the function tegra210_pll_init(), the OVERRIDE bit for pll_u is cleared, which selects hardware control of the pll. However, at the same time the pll_u clocks are populated in the init_table for tegra210 and so software will try to configure the pll_u if it is not already configured and hence, the above warning is seen when the pll fails to lock. Remove the pll_u clocks from the init_table so that software does not try to configure this pll on boot. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Rhyland Klein <rklein@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com>
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