arm: tegra: turn off pll-a/p in LP1

- current code does not turn off pll-a/p in LP1
irrespective of voice call status
- add a new flag to indicate voice call on-going
- use PMC_SCRATCH37 to hold this flag
- if it is set, do not turn-off pll-a/p during LP1
- save-restore PMC_SCRATCH37 if it was used to hold the
voice call on-going flag
- fix few misc formatting issues in tegra3_cpu_clk32k

Bug 924817

Signed-off-by: Mayuresh Kulkarni <[email protected]>
Reviewed-on: http://git-master/r/85768
(cherry picked from commit 7853981c987ae329620bb54d869016cb74a6c054)

Change-Id: Id5348d2eb44a4bacaf00f6d17edceedaef819e29
Reviewed-on: http://git-master/r/94395
Tested-by: Mayuresh Kulkarni <[email protected]>
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Bharat Nihalani <[email protected]>

Author: Mayuresh Kulkarni

arch/arm/mach-tegra/pm.c

@@ -43,6 +43,7 @@
 #include <linux/memblock.h>
 #include <linux/console.h>
 #include <linux/pm_qos_params.h>
+#include <linux/tegra_audio.h>
 
 #include <asm/cacheflush.h>
 #include <asm/cpu_pm.h>
@@ -837,13 +838,25 @@ static void tegra_suspend_check_pwr_stats(void)
 int tegra_suspend_dram(enum tegra_suspend_mode mode, unsigned int flags)
 {
 	int err = 0;
+	u32 scratch37 = 0xDEADBEEF;
 
 	if (WARN_ON(mode <= TEGRA_SUSPEND_NONE ||
 		mode >= TEGRA_MAX_SUSPEND_MODE)) {
 		err = -ENXIO;
 		goto fail;
 	}
 
+	if (tegra_is_voice_call_active()) {
+		u32 reg;
+
+		/* backup the current value of scratch37 */
+		scratch37 = readl(pmc + PMC_SCRATCH37);
+
+		/* If voice call is active, set a flag in PMC_SCRATCH37 */
+		reg = TEGRA_POWER_LP1_AUDIO;
+		pmc_32kwritel(reg, PMC_SCRATCH37);
+	}
+
 	if ((mode == TEGRA_SUSPEND_LP0) && !tegra_pm_irq_lp0_allowed()) {
 		pr_info("LP0 not used due to unsupported wakeup events\n");
 		mode = TEGRA_SUSPEND_LP1;
@@ -899,6 +912,10 @@ int tegra_suspend_dram(enum tegra_suspend_mode mode, unsigned int flags)
 	} else if (mode == TEGRA_SUSPEND_LP1)
 		*iram_cpu_lp1_mask = 0;
 
+	/* if scratch37 was clobbered during LP1, restore it */
+	if (scratch37 != 0xDEADBEEF)
+		pmc_32kwritel(scratch37, PMC_SCRATCH37);
+
 	restore_cpu_complex(flags);
 
 	/* for platforms where the core & CPU power requests are

arch/arm/mach-tegra/sleep-t3.S

@@ -519,7 +519,7 @@ tegra3_cpu_clk32k:
 
 	/* enable PLLM via PMC in LP0 */
 	ldr	r0, [r4, #PMC_PLLP_WB0_OVERRIDE]
-	orr	r0, r0, #((1<<12) | (1 << 11))
+	orr	r0, r0, #((1 << 12) | (1 << 11))
 	str	r0, [r4, #PMC_PLLP_WB0_OVERRIDE]
 	mov	pc, lr
 
@@ -543,29 +543,28 @@ lp1_clocks_prepare:
 	add	r1, r1, #2
 	wait_until r1, r7, r9
 
-#if 1
 	/* switch to CLKS */
 	mov	r0, #0	/* burst policy = 32KHz */
 	str	r0, [r5, #CLK_RESET_SCLK_BURST]
-#endif
 
 	/* disable PLLM via PMC in LP1 */
 	ldr	r0, [r4, #PMC_PLLP_WB0_OVERRIDE]
-	bic	r0, r0, #(1<<12)
+	bic	r0, r0, #(1 << 12)
 	str	r0, [r4, #PMC_PLLP_WB0_OVERRIDE]
 	b	powerdown_pll_pcx
 
 powerdown_pll_pcx:
-	/* disable PLLP, PLLA, PLLC, and PLLX in LP0 and LP1 states */
-	ldr	r0, [r4, #PMC_CTRL]
-	tst	r0, #PMC_CTRL_SIDE_EFFECT_LP0
-	beq	powerdown_pll_cx
+	ldr	r11, [r4, #PMC_SCRATCH37]	@ load the LP1 flags
+	tst	r11, #TEGRA_POWER_LP1_AUDIO	@ check if voice call is going on
+	bne	powerdown_pll_cx		@ if yes, do not turn off pll-p/pll-a
+
 	ldr	r0, [r5, #CLK_RESET_PLLP_BASE]
 	bic	r0, r0, #(1<<30)
 	str	r0, [r5, #CLK_RESET_PLLP_BASE]
 	ldr	r0, [r5, #CLK_RESET_PLLA_BASE]
 	bic	r0, r0, #(1<<30)
 	str	r0, [r5, #CLK_RESET_PLLA_BASE]
+
 powerdown_pll_cx:
 	ldr	r0, [r5, #CLK_RESET_PLLC_BASE]
 	bic	r0, r0, #(1<<30)

arch/arm/mach-tegra/sleep.h

@@ -38,6 +38,7 @@
 #define USE_TEGRA_DIAG_REG_SAVE	0
 #endif
 
+#define TEGRA_POWER_LP1_AUDIO		(1 << 25) /* do not turn off pll-p in LP1 */
 #define TEGRA_POWER_SDRAM_SELFREFRESH	(1 << 26) /* SDRAM is in self-refresh */
 #define TEGRA_POWER_HOTPLUG_SHUTDOWN	(1 << 27) /* Hotplug shutdown */
 #define TEGRA_POWER_CLUSTER_G		(1 << 28) /* G CPU */