[PATCH 09/18] ARM: vf610: clk: add suspend/resume support

Stefan Agner
2016-03-10T02:16:50Z

The clock register are lost when enterying LPSTOPx, hence provide
suspend/resume functions restoring them. The clock gates get
restored by the individual driver, hence we do not need to restore
them here.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
drivers/clk/imx/clk-vf610.c | 49 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)

diff --git a/drivers/clk/imx/clk-vf610.c b/drivers/clk/imx/clk-vf610.c
index 610a724..e2e2c43 100644
--- a/drivers/clk/imx/clk-vf610.c
+++ b/drivers/clk/imx/clk-vf610.c
@@ -10,6 +10,7 @@

#include <linux/of_address.h>
#include <linux/clk.h>
+#include <linux/syscore_ops.h>
#include <dt-bindings/clock/vf610-clock.h>

#include "clk.h"
@@ -40,6 +41,7 @@
#define CCM_CCGR9 (ccm_base + 0x64)
#define CCM_CCGR10 (ccm_base + 0x68)
#define CCM_CCGR11 (ccm_base + 0x6c)
+#define CCM_CCGRx(x) (CCM_CCGR0 + (x) * 4)
#define CCM_CMEOR0 (ccm_base + 0x70)
#define CCM_CMEOR1 (ccm_base + 0x74)
#define CCM_CMEOR2 (ccm_base + 0x78)
@@ -115,6 +117,13 @@ static struct clk_div_table pll4_audio_div_table[] = {
static struct clk *clk[VF610_CLK_END];
static struct clk_onecell_data clk_data;

+static u32 cscmr1;
+static u32 cscmr2;
+static u32 cscdr1;
+static u32 cscdr2;
+static u32 cscdr3;
+static u32 ccgr[12];
+
static unsigned int const clks_init_on[] __initconst = {
VF610_CLK_SYS_BUS,
VF610_CLK_DDR_SEL,
@@ -134,6 +143,43 @@ static struct clk * __init vf610_get_fixed_clock(
return clk;
};

+static int vf610_clk_suspend(void)
+{
+ int i;
+
+ cscmr1 = readl_relaxed(CCM_CSCMR1);
+ cscmr2 = readl_relaxed(CCM_CSCMR2);
+
+ cscdr1 = readl_relaxed(CCM_CSCDR1);
+ cscdr2 = readl_relaxed(CCM_CSCDR2);
+ cscdr3 = readl_relaxed(CCM_CSCDR3);
+
+ for (i = 0; i < 12; i++)
+ ccgr[i] = readl_relaxed(CCM_CCGRx(i));
+
+ return 0;
+}
+
+static void vf610_clk_resume(void)
+{
+ int i;
+
+ writel_relaxed(cscmr1, CCM_CSCMR1);
+ writel_relaxed(cscmr2, CCM_CSCMR2);
+
+ writel_relaxed(cscdr1, CCM_CSCDR1);
+ writel_relaxed(cscdr2, CCM_CSCDR2);
+ writel_relaxed(cscdr3, CCM_CSCDR3);
+
+ for (i = 0; i < 12; i++)
+ writel_relaxed(ccgr[i], CCM_CCGRx(i));
+}
+
+static struct syscore_ops vf610_clk_syscore_ops = {
+ .suspend = vf610_clk_suspend,
+ .resume = vf610_clk_resume,
+};
+
static void __init vf610_clocks_init(struct device_node *ccm_node)
{
struct device_node *np;
@@ -414,9 +460,12 @@ static void __init vf610_clocks_init(struct device_node *ccm_node)
for (i = 0; i < ARRAY_SIZE(clks_init_on); i++)
clk_prepare_enable(clk[clks_init_on[i]]);

+ register_syscore_ops(&vf610_clk_syscore_ops);
+
/* Add the clocks to provider list */
clk_data.clks = clk;
clk_data.clk_num = ARRAY_SIZE(clk);
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
}
CLK_OF_DECLARE(vf610, "fsl,vf610-ccm", vf610_clocks_init);
+
--
2.7.2