Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 05:02:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

clk: samsung: exynos4: Enable VPLL and EPLL clocks for suspend/resume cycle

Browse Source 
Commit 6edfa11cb3 ("clk: samsung: Add enable/disable operation for
PLL36XX clocks") added enable/disable operations to PLL clocks. Prior that
VPLL and EPPL clocks were always enabled because the enable bit was never
touched. Those clocks have to be enabled during suspend/resume cycle,
because otherwise board fails to enter sleep mode. This patch enables them
unconditionally before entering system suspend state. System restore
function will set them to the previous state saved in the register cache
done before that unconditional enable.

Fixes: 6edfa11cb3 ("clk: samsung: Add enable/disable operation for PLL36XX clocks")
CC: stable@vger.kernel.org # v4.13
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This commit is contained in:
Marek Szyprowski 2017-09-19 12:01:08 +02:00 committed by Stephen Boyd
parent 79765e9a3d
commit 5dcbeca615
1 changed files with 15 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
drivers/clk/samsung/clk-exynos4.c
View File

@ -294,6 +294,18 @@ static const struct samsung_clk_reg_dump src_mask_suspend_e4210[] = {
#define PLL_ENABLED (1 << 31)
#define PLL_LOCKED (1 << 29)
static void exynos4_clk_enable_pll(u32 reg)
{
u32 pll_con = readl(reg_base + reg);
pll_con |= PLL_ENABLED;
writel(pll_con, reg_base + reg);
while (!(pll_con & PLL_LOCKED)) {
cpu_relax();
pll_con = readl(reg_base + reg);
}
}
static void exynos4_clk_wait_for_pll(u32 reg)
{
u32 pll_con;
@ -315,6 +327,9 @@ static int exynos4_clk_suspend(void)
samsung_clk_save(reg_base, exynos4_save_pll,
ARRAY_SIZE(exynos4_clk_pll_regs));
exynos4_clk_enable_pll(EPLL_CON0);
exynos4_clk_enable_pll(VPLL_CON0);
if (exynos4_soc == EXYNOS4210) {
samsung_clk_save(reg_base, exynos4_save_soc,
ARRAY_SIZE(exynos4210_clk_save));