[PATCH 4.14 092/178] clk: tegra: Use readl_relaxed_poll_timeout_atomic() in tegra210_clock_init()

From: Greg Kroah-Hartman
Date: Mon Dec 18 2017 - 11:14:47 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Nicolin Chen <nicoleotsuka@xxxxxxxxx>


[ Upstream commit 22ef01a203d27fee8b7694020b7e722db7efd2a7 ]

Below is the call trace of tegra210_init_pllu() function:
start_kernel()
-> time_init()
--> of_clk_init()
---> tegra210_clock_init()
----> tegra210_pll_init()
-----> tegra210_init_pllu()

Because the preemption is disabled in the start_kernel before calling
time_init, tegra210_init_pllu is actually in an atomic context while
it includes a readl_relaxed_poll_timeout that might sleep.

So this patch just changes this readl_relaxed_poll_timeout() to its
atomic version.

Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
Acked-By: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/clk/tegra/clk-tegra210.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -2566,8 +2566,8 @@ static int tegra210_enable_pllu(void)
reg |= PLL_ENABLE;
writel(reg, clk_base + PLLU_BASE);

- readl_relaxed_poll_timeout(clk_base + PLLU_BASE, reg,
- reg & PLL_BASE_LOCK, 2, 1000);
+ readl_relaxed_poll_timeout_atomic(clk_base + PLLU_BASE, reg,
+ reg & PLL_BASE_LOCK, 2, 1000);
if (!(reg & PLL_BASE_LOCK)) {
pr_err("Timed out waiting for PLL_U to lock\n");
return -ETIMEDOUT;