From: Stephen Warren swarren@nvidia.com
commit bf83b96f87ae2abb1e535306ea53608e8de5dfbb upstream.
For a little over a year, U-Boot on Tegra124 has configured the flow controller to perform automatic RAM re-repair on off->on power transitions of the CPU rail[1]. This is mandatory for correct operation of Tegra124. However, RAM re-repair relies on certain clocks, which the kernel must enable and leave running. The fuse clock is one of those clocks. Mark this clock as critical so that LP1 power mode (system suspend) operates correctly.
[1] 3cc7942a4ae5 ARM: tegra: implement RAM repair
Reported-by: Jonathan Hunter jonathanh@nvidia.com Cc: stable@vger.kernel.org Signed-off-by: Stephen Warren swarren@nvidia.com Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/clk/tegra/clk-tegra-periph.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/clk/tegra/clk-tegra-periph.c +++ b/drivers/clk/tegra/clk-tegra-periph.c @@ -785,7 +785,11 @@ static struct tegra_periph_init_data gat GATE("ahbdma", "hclk", 33, 0, tegra_clk_ahbdma, 0), GATE("apbdma", "pclk", 34, 0, tegra_clk_apbdma, 0), GATE("kbc", "clk_32k", 36, TEGRA_PERIPH_ON_APB | TEGRA_PERIPH_NO_RESET, tegra_clk_kbc, 0), - GATE("fuse", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse, 0), + /* + * Critical for RAM re-repair operation, which must occur on resume + * from LP1 system suspend and as part of CCPLEX cluster switching. + */ + GATE("fuse", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse, CLK_IS_CRITICAL), GATE("fuse_burn", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse_burn, 0), GATE("kfuse", "clk_m", 40, TEGRA_PERIPH_ON_APB, tegra_clk_kfuse, 0), GATE("apbif", "clk_m", 107, TEGRA_PERIPH_ON_APB, tegra_clk_apbif, 0),