x86/apb_timer: Remove driver for deprecated platform

Intel Moorestown and Medfield are quite old Intel Atom based
32-bit platforms, which were in limited use in some Android phones,
tablets and consumer electronics more than eight years ago.

There are no bugs or problems ever reported outside from Intel
for breaking any of that platforms for years. It seems no real
users exists who run more or less fresh kernel on it. Commit
05f4434 ("ASoC: Intel: remove mfld_machine") is also in align
with this theory.

Due to above and to reduce a burden of supporting outdated drivers,
remove the support for outdated platforms completely.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Documentation/admin-guide/kernel-parameters.txt

@@ -5932,12 +5932,6 @@
 			default x2apic cluster mode on platforms
 			supporting x2apic.
 
-	x86_intel_mid_timer= [X86-32,APBT]
-			Choose timer option for x86 Intel MID platform.
-			Two valid options are apbt timer only and lapic timer
-			plus one apbt timer for broadcast timer.
-			x86_intel_mid_timer=apbt_only | lapic_and_apbt
-
 	xen_512gb_limit		[KNL,X86-64,XEN]
 			Restricts the kernel running paravirtualized under Xen
 			to use only up to 512 GB of RAM. The reason to do so is

arch/x86/Kconfig

@@ -892,18 +892,6 @@ config HPET_EMULATE_RTC
 	def_bool y
 	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 
-config APB_TIMER
-	def_bool y if X86_INTEL_MID
-	prompt "Intel MID APB Timer Support" if X86_INTEL_MID
-	select DW_APB_TIMER
-	depends on X86_INTEL_MID && SFI
-	help
-	 APB timer is the replacement for 8254, HPET on X86 MID platforms.
-	 The APBT provides a stable time base on SMP
-	 systems, unlike the TSC, but it is more expensive to access,
-	 as it is off-chip. APB timers are always running regardless of CPU
-	 C states, they are used as per CPU clockevent device when possible.
-
 # Mark as expert because too many people got it wrong.
 # The code disables itself when not needed.
 config DMI

arch/x86/include/asm/intel-mid.h

@@ -23,7 +23,6 @@ extern void intel_mid_pwr_power_off(void);
 extern int intel_mid_pwr_get_lss_id(struct pci_dev *pdev);
 
 extern int get_gpio_by_name(const char *name);
-extern int __init sfi_parse_mtmr(struct sfi_table_header *table);
 
 /*
  * Here defines the array of devices platform data that IAFW would export
@@ -91,14 +90,6 @@ static inline void intel_scu_devices_destroy(void) { }
 
 #endif /* !CONFIG_X86_INTEL_MID */
 
-enum intel_mid_timer_options {
-	INTEL_MID_TIMER_DEFAULT,
-	INTEL_MID_TIMER_APBT_ONLY,
-	INTEL_MID_TIMER_LAPIC_APBT,
-};
-
-extern enum intel_mid_timer_options intel_mid_timer_options;
-
 /* Bus Select SoC Fuse value */
 #define BSEL_SOC_FUSE_MASK		0x7
 /* FSB 133MHz */
@@ -108,8 +99,6 @@ extern enum intel_mid_timer_options intel_mid_timer_options;
 /* FSB 83MHz */
 #define BSEL_SOC_FUSE_111		0x7
 
-#define SFI_MTMR_MAX_NUM		8
-
 /* The offset for the mapping of global gpio pin to irq */
 #define INTEL_MID_IRQ_OFFSET		0x100
 

arch/x86/kernel/Makefile

@@ -116,7 +116,6 @@ obj-$(CONFIG_VM86)		+= vm86_32.o
 obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 
 obj-$(CONFIG_HPET_TIMER) 	+= hpet.o
-obj-$(CONFIG_APB_TIMER)		+= apb_timer.o
 
 obj-$(CONFIG_AMD_NB)		+= amd_nb.o
 obj-$(CONFIG_DEBUG_NMI_SELFTEST) += nmi_selftest.o