clk: tegra: Mark fuse clock as critical - build failed on 4.4-stable tree

clk: tegra: Mark fuse clock as critical - build failed on 4.4-stable tree

[Naresh Kamboju]

This patch caused build failed on stable rc 4.4 branch for arm64
Juno-r2 device and arm beagleboard x15 device

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(-)

(limited to 'drivers/clk/tegra/clk-tegra-periph.c')

diff --git a/drivers/clk/tegra/clk-tegra-periph.c
b/drivers/clk/tegra/clk-tegra-periph.c
index cb6ab83..eb04d99 100644
--- a/drivers/clk/tegra/clk-tegra-periph.c
+++ b/drivers/clk/tegra/clk-tegra-periph.c
@@ -516,7 +516,11 @@ static struct tegra_periph_init_data gate_clks[] = {
  GATE("vcp", "clk_m", 29, 0, tegra_clk_vcp, 0),
  GATE("apbdma", "clk_m", 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),

ref:
https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-4.4/DISTRO=lkft,MACHINE=juno,label=docker-lkft/742/console
https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-4.4/DISTRO=lkft,MACHINE=am57xx-evm,label=docker-lkft/742/console

-- 
Linaro LKFT
https://lkft.linaro.org

Re: clk: tegra: Mark fuse clock as critical - build failed on 4.4-stable tree

[Greg Kroah-Hartman]

On Mon, Feb 10, 2020 at 11:49:52AM +0530, Naresh Kamboju wrote:
> This patch caused build failed on stable rc 4.4 branch for arm64
> Juno-r2 device and arm beagleboard x15 device
> 
> commit bf83b96f87ae2abb1e535306ea53608e8de5dfbb upstream.

THanks for letting me know, I've now dropped it from the tree.

greg k-h