From ee525c2597c78c98a3988d403d4859e4cfd78ed5 Mon Sep 17 00:00:00 2001
From: "Charles E. Youse" <charles.youse@intel.com>
Date: Wed, 11 Sep 2019 14:20:49 -0400
Subject: [PATCH] arch/x86: inline x2APIC EOI

From the Jailhouse days, this has been a function call. That's silly.
We now inline the EOI in the ISR when in x2APIC mode. Also clean up
z_irq_controller_eoi(), so it now uses the inline macros.

Also, we now enable x2APIC on up_squared by default.

Fixes: #17133

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
---
 arch/x86/core/ia32/intstub.S                   |  8 +++++---
 boards/x86/up_squared/up_squared_defconfig     |  1 +
 include/drivers/interrupt_controller/loapic.h  | 12 ++++++------
 include/drivers/interrupt_controller/sysapic.h | 10 +---------
 4 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/arch/x86/core/ia32/intstub.S b/arch/x86/core/ia32/intstub.S
index 3882f537857..a904f934874 100644
--- a/arch/x86/core/ia32/intstub.S
+++ b/arch/x86/core/ia32/intstub.S
@@ -204,10 +204,12 @@ alreadyOnIntStack:
 	cli			/* disable interrupts again */
 #endif
 
-#if defined(CONFIG_X2APIC)
-	call	z_x2apic_eoi
-#else /* xAPIC EOI */
 	xorl	%eax, %eax
+#if defined(CONFIG_X2APIC)
+	xorl	%edx, %edx
+	movl	$(X86_X2APIC_BASE_MSR + (LOAPIC_EOI >> 4)), %ecx
+	wrmsr
+#else /* xAPIC */
 	movl	%eax, (CONFIG_LOAPIC_BASE_ADDRESS + LOAPIC_EOI)
 #endif
 
diff --git a/boards/x86/up_squared/up_squared_defconfig b/boards/x86/up_squared/up_squared_defconfig
index 3ee096aabf3..c88952e25f7 100644
--- a/boards/x86/up_squared/up_squared_defconfig
+++ b/boards/x86/up_squared/up_squared_defconfig
@@ -11,3 +11,4 @@ CONFIG_SERIAL=y
 CONFIG_UART_NS16550=y
 CONFIG_UART_CONSOLE=y
 CONFIG_I2C=y
+CONFIG_X2APIC=y
diff --git a/include/drivers/interrupt_controller/loapic.h b/include/drivers/interrupt_controller/loapic.h
index 255276fa738..4a0c1b35877 100644
--- a/include/drivers/interrupt_controller/loapic.h
+++ b/include/drivers/interrupt_controller/loapic.h
@@ -12,10 +12,6 @@
 #include <arch/cpu.h>
 #include <arch/x86/msr.h>
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /* Local APIC Register Offset */
 
 #define LOAPIC_ID 0x020		  /* Local APIC ID Reg */
@@ -49,6 +45,10 @@ extern "C" {
 
 #ifndef _ASMLANGUAGE
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 extern void z_loapic_int_vec_set(unsigned int irq, unsigned int vector);
 extern void z_loapic_irq_enable(unsigned int irq);
 extern void z_loapic_irq_disable(unsigned int irq);
@@ -136,10 +136,10 @@ static inline void x86_write_loapic(unsigned int reg, u32_t val)
 #endif
 }
 
-#endif /* _ASMLANGUAGE */
-
 #ifdef __cplusplus
 }
 #endif
 
+#endif /* _ASMLANGUAGE */
+
 #endif /* ZEPHYR_INCLUDE_DRIVERS_LOAPIC_H_ */
diff --git a/include/drivers/interrupt_controller/sysapic.h b/include/drivers/interrupt_controller/sysapic.h
index f01babe2555..355815274ba 100644
--- a/include/drivers/interrupt_controller/sysapic.h
+++ b/include/drivers/interrupt_controller/sysapic.h
@@ -26,17 +26,9 @@ void z_irq_controller_irq_config(unsigned int vector, unsigned int irq,
 
 int z_irq_controller_isr_vector_get(void);
 
-#ifdef CONFIG_X2APIC
-void z_x2apic_eoi(void);
-#endif
-
 static inline void z_irq_controller_eoi(void)
 {
-#if defined(CONFIG_X2APIC)
-	z_x2apic_eoi();
-#else /* xAPIC */
-	*(volatile int *)(CONFIG_LOAPIC_BASE_ADDRESS + LOAPIC_EOI) = 0;
-#endif
+	x86_write_loapic(LOAPIC_EOI, 0);
 }
 
 #endif /* _ASMLANGUAGE */