From 6aedb6ff1a898a1a832e86880de5eb5733b9c085 Mon Sep 17 00:00:00 2001
From: "Charles E. Youse" <charles.youse@intel.com>
Date: Tue, 4 Jun 2019 09:39:59 -0700
Subject: [PATCH] arch/x86: disable i8259 in crt0.S

drivers/interrupt_controller/i8259.c is not a driver; it exists
solely to disable the i8259s when the configuration calls for it.
The six-byte sequence to mask the controllers is moved to crt0.S
and the pseudo-driver is removed.

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
---
 arch/x86/core/crt0.S                        | 11 +++++
 drivers/interrupt_controller/CMakeLists.txt |  1 -
 drivers/interrupt_controller/i8259.c        | 53 ---------------------
 3 files changed, 11 insertions(+), 54 deletions(-)
 delete mode 100644 drivers/interrupt_controller/i8259.c

diff --git a/arch/x86/core/crt0.S b/arch/x86/core/crt0.S
index 0419e0502de..8b4d273bb1b 100644
--- a/arch/x86/core/crt0.S
+++ b/arch/x86/core/crt0.S
@@ -415,6 +415,17 @@ __csSet:
 1:
 #endif
 
+#if defined(CONFIG_PIC_DISABLE)
+	/*
+	 * "Disable" legacy i8259 interrupt controllers. Note that we
+	 * can't actually disable them, but we mask all their interrupt
+	 * sources which is effectively the same thing (almost).
+	 */
+	movb $0xff, %al		/* all bits set = mask all interrupts */
+	outb %al, $0x21		/* set i8259 master mask (IRQs 0-7) */
+	outb %al, $0xA1		/* set i8259 slave mask (IRQs 8-15) */
+#endif
+
 	/* Jump to C portion of kernel initialization and never return */
 
 	jmp	z_cstart
diff --git a/drivers/interrupt_controller/CMakeLists.txt b/drivers/interrupt_controller/CMakeLists.txt
index 4188ed84c08..d7f8ba5eadb 100644
--- a/drivers/interrupt_controller/CMakeLists.txt
+++ b/drivers/interrupt_controller/CMakeLists.txt
@@ -5,7 +5,6 @@ zephyr_sources_ifdef(CONFIG_IOAPIC                  ioapic_intr.c)
 zephyr_sources_ifdef(CONFIG_LOAPIC                  loapic_intr.c system_apic.c)
 zephyr_sources_ifdef(CONFIG_LOAPIC_SPURIOUS_VECTOR  loapic_spurious.S)
 zephyr_sources_ifdef(CONFIG_MVIC                    mvic.c)
-zephyr_sources_ifdef(CONFIG_PIC_DISABLE             i8259.c)
 zephyr_sources_ifdef(CONFIG_PLIC                    plic.c)
 zephyr_sources_ifdef(CONFIG_SHARED_IRQ              shared_irq.c)
 zephyr_sources_ifdef(CONFIG_EXTI_STM32              exti_stm32.c)
diff --git a/drivers/interrupt_controller/i8259.c b/drivers/interrupt_controller/i8259.c
deleted file mode 100644
index 75f10eae787..00000000000
--- a/drivers/interrupt_controller/i8259.c
+++ /dev/null
@@ -1,53 +0,0 @@
-/*
- * Copyright (c) 2010-2015 Wind River Systems, Inc.
- *
- * SPDX-License-Identifier: Apache-2.0
- */
-
-/**
- * @file
- * @brief Disable Intel 8259A PIC (Programmable Interrupt Controller)
- *
- * This module disables the Intel 8259A PIC (Programmable Interrupt Controller)
- * to prevent it from generating spurious interrupts.
- */
-
-
-#include <kernel.h>
-#include <arch/cpu.h>
-#include <toolchain.h>
-#include <linker/sections.h>
-#include <device.h>
-#include <init.h>
-
-/* programmable interrupt controller info (pair of cascaded 8259A devices) */
-#define PIC_MASTER_BASE_ADRS 0x20
-#define PIC_SLAVE_BASE_ADRS 0xa0
-#define PIC_REG_ADDR_INTERVAL 1
-
-/* register definitions */
-#define PIC_ADRS(baseAdrs, reg) (baseAdrs + (reg * PIC_REG_ADDR_INTERVAL))
-
-#define PIC_PORT2(base) PIC_ADRS(base, 0x01) /* port 2 */
-
-#define PIC_DISABLE 0xff /* Disable PIC command */
-
-/**
- *
- * @brief Initialize the Intel 8259A PIC device driver
- *
- * This routine disables the 8259A PIC device to prevent it from
- * generating spurious interrupts.
- *
- * @return N/A
- */
-
-int _i8259_init(struct device *unused)
-{
-	ARG_UNUSED(unused);
-	sys_out8(PIC_DISABLE, PIC_PORT2(PIC_SLAVE_BASE_ADRS));
-	sys_out8(PIC_DISABLE, PIC_PORT2(PIC_MASTER_BASE_ADRS));
-	return 0;
-}
-
-SYS_INIT(_i8259_init, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);