dm: timer: normalise SPL and TPL support

To fully support DM timer in SPL and TPL, we need a few things cleaned
up and normalised:
- inclusion of the uclass and drivers should be an all-or-nothing
  decision for each stage and under control of $(SPL_TPL_)TIMER
  instead of having the two-level configuration with TIMER and
  $(SPL_TPL_)TIMER_SUPPORT
- when $(SPL_TPL_)TIMER is enabled, the ARMv8 generic timer code can
  not be compiled in

This normalises configuration to $(SPL_TPL_)TIMER and moves the config
options to drivers/timer/Kconfig (and cleans up the collateral damage
to some defconfigs that had SPL_TIMER_SUPPORT enabled).

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/arm/cpu/armv8/Makefile

@@ -8,7 +8,9 @@
 extra-y	:= start.o
 
 obj-y	+= cpu.o
+ifndef CONFIG_$(SPL_TPL_)TIMER
 obj-y	+= generic_timer.o
+endif
 obj-y	+= cache_v8.o
 obj-y	+= exceptions.o
 obj-y	+= cache.o

common/spl/Kconfig

@@ -603,14 +603,6 @@ config SPL_SPI_SUPPORT
 	  enable SPI drivers that are needed for other purposes also, such
 	  as a SPI PMIC.
 
-config SPL_TIMER_SUPPORT
-	bool "Support timer drivers"
-	help
-	  Enable support for timer drivers in SPL. These can be used to get
-	  a timer value when in SPL, or perhaps for implementing a delay
-	  function. This enables the drivers in drivers/timer as part of an
-	  SPL build.
-
 config SPL_USB_HOST_SUPPORT
 	bool "Support USB host drivers"
 	help

configs/chromebook_link64_defconfig

@@ -27,7 +27,7 @@ CONFIG_SPL_NET_SUPPORT=y
 CONFIG_SPL_PCI_SUPPORT=y
 CONFIG_SPL_PCH_SUPPORT=y
 CONFIG_SPL_RTC_SUPPORT=y
-CONFIG_SPL_TIMER_SUPPORT=y
+CONFIG_SPL_TIMER=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_CPU=y
 # CONFIG_CMD_BOOTEFI_HELLO_COMPILE is not set

configs/qemu-x86_64_defconfig

@@ -26,7 +26,7 @@ CONFIG_SPL_NET_SUPPORT=y
 CONFIG_SPL_PCI_SUPPORT=y
 CONFIG_SPL_PCH_SUPPORT=y
 CONFIG_SPL_RTC_SUPPORT=y
-CONFIG_SPL_TIMER_SUPPORT=y
+CONFIG_SPL_TIMER=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_CPU=y
 # CONFIG_CMD_BOOTEFI_HELLO_COMPILE is not set

drivers/Makefile

@@ -15,6 +15,7 @@ obj-$(CONFIG_$(SPL_TPL_)RAM) += ram/
 obj-$(CONFIG_$(SPL_TPL_)SERIAL_SUPPORT) += serial/
 obj-$(CONFIG_$(SPL_TPL_)SPI_FLASH_SUPPORT) += mtd/spi/
 obj-$(CONFIG_$(SPL_TPL_)SPI_SUPPORT) += spi/
+obj-$(CONFIG_$(SPL_TPL_)TIMER) += timer/
 
 ifndef CONFIG_TPL_BUILD
 ifdef CONFIG_SPL_BUILD
@@ -38,7 +39,6 @@ obj-$(CONFIG_SPL_USBETH_SUPPORT) += net/phy/
 obj-$(CONFIG_SPL_PCI_SUPPORT) += pci/
 obj-$(CONFIG_SPL_PCH_SUPPORT) += pch/
 obj-$(CONFIG_SPL_RTC_SUPPORT) += rtc/
-obj-$(CONFIG_SPL_TIMER_SUPPORT) += timer/
 obj-$(CONFIG_SPL_MUSB_NEW_SUPPORT) += usb/musb-new/
 obj-$(CONFIG_SPL_USB_GADGET_SUPPORT) += usb/gadget/
 obj-$(CONFIG_SPL_USB_GADGET_SUPPORT) += usb/gadget/udc/
@@ -83,7 +83,6 @@ obj-y += scsi/
 obj-y += sound/
 obj-y += spmi/
 obj-y += sysreset/
-obj-y += timer/
 obj-y += tpm/
 obj-y += video/
 obj-y += watchdog/

drivers/timer/Kconfig

@@ -9,6 +9,24 @@ config TIMER
 	  will be used. The timer is usually a 32 bits free-running up
 	  counter. There may be no real tick, and no timer interrupt.
 
+config SPL_TIMER
+	bool "Enable driver model for timer drivers in SPL"
+	depends on TIMER && SPL
+	help
+	  Enable support for timer drivers in SPL. These can be used to get
+	  a timer value when in SPL, or perhaps for implementing a delay
+	  function. This enables the drivers in drivers/timer as part of an
+	  SPL build.
+
+config TPL_TIMER
+	bool "Enable driver model for timer drivers in TPL"
+	depends on TIMER && TPL
+	help
+	  Enable support for timer drivers in TPL. These can be used to get
+	  a timer value when in TPL, or perhaps for implementing a delay
+	  function. This enables the drivers in drivers/timer as part of an
+	  TPL build.
+
 config TIMER_EARLY
 	bool "Allow timer to be used early in U-Boot"
 	depends on TIMER

drivers/timer/Makefile

@@ -4,7 +4,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-$(CONFIG_TIMER)		+= timer-uclass.o
+obj-y += timer-uclass.o
 obj-$(CONFIG_ALTERA_TIMER)	+= altera_timer.o
 obj-$(CONFIG_SANDBOX_TIMER)	+= sandbox_timer.o
 obj-$(CONFIG_X86_TSC_TIMER)	+= tsc_timer.o