Add support for the Tegra210 timer that runs at oscillator clock
(TMR10-TMR13). We need these timers to work as clock event device and to
replace the ARMv8 architected timer due to it can't survive across the
power cycle of the CPU core or CPUPORESET signal. So it can't be a wake-up
source when CPU suspends in power down state.

Also convert the original driver to use timer-of API.

Cc: Daniel Lezcano <redacted>
Cc: Thomas Gleixner <redacted>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Joseph Lo <redacted>
Acked-by: Thierry Reding <redacted>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
---
v6:
 * refine the timer defines
 * add ack tag from Jon.
v5:
 * add ack tag from Thierry
v4:
 * merge timer-tegra210.c in previous version into timer-tegra20.c
v3:
 * use timer-of API
v2:
 * add error clean-up code
---
 drivers/clocksource/Kconfig         |   2 +-
 drivers/clocksource/timer-tegra20.c | 371 ++++++++++++++++++++--------
 include/linux/cpuhotplug.h          |   1 +
 3 files changed, 270 insertions(+), 104 deletions(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index a9e26f6a81a1..6af78534a285 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig

@@ -131,7 +131,7 @@ config SUN5I_HSTIMER
 config TEGRA_TIMER
 	bool "Tegra timer driver" if COMPILE_TEST
 	select CLKSRC_MMIO
-	depends on ARM
+	select TIMER_OF
 	help
 	  Enables support for the Tegra driver.
 

diff --git a/drivers/clocksource/timer-tegra20.c b/drivers/clocksource/timer-tegra20.c
index 4293943f4e2b..f66edd63d7f4 100644
--- a/drivers/clocksource/timer-tegra20.c
+++ b/drivers/clocksource/timer-tegra20.c

@@ -15,21 +15,24 @@
  *
  */
 
-#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/delay.h>
 #include <linux/err.h>
-#include <linux/time.h>
 #include <linux/interrupt.h>
-#include <linux/irq.h>
-#include <linux/clockchips.h>
-#include <linux/clocksource.h>
-#include <linux/clk.h>
-#include <linux/io.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
-#include <linux/sched_clock.h>
-#include <linux/delay.h>
+#include <linux/percpu.h>
+#include <linux/syscore_ops.h>
+#include <linux/time.h>
+
+#include "timer-of.h"
 
+#ifdef CONFIG_ARM
 #include <asm/mach/time.h>
+#endif
 
 #define RTC_SECONDS            0x08
 #define RTC_SHADOW_SECONDS     0x0c

@@ -39,74 +42,145 @@
 #define TIMERUS_USEC_CFG 0x14
 #define TIMERUS_CNTR_FREEZE 0x4c
 
-#define TIMER1_BASE 0x0
-#define TIMER2_BASE 0x8
-#define TIMER3_BASE 0x50
-#define TIMER4_BASE 0x58
-
-#define TIMER_PTV 0x0
-#define TIMER_PCR 0x4
-
+#define TIMER_PTV		0x0
+#define TIMER_PTV_EN		BIT(31)
+#define TIMER_PTV_PER		BIT(30)
+#define TIMER_PCR		0x4
+#define TIMER_PCR_INTR_CLR	BIT(30)
+
+#ifdef CONFIG_ARM
+#define TIMER_CPU0		0x50 /* TIMER3 */
+#else
+#define TIMER_CPU0		0x90 /* TIMER10 */
+#define TIMER10_IRQ_IDX		10
+#define IRQ_IDX_FOR_CPU(cpu)	(TIMER10_IRQ_IDX + cpu)
+#endif
+#define TIMER_BASE_FOR_CPU(cpu) (TIMER_CPU0 + (cpu) * 8)