Merge tag 'x86-irq-2021-08-30' of git://git.kernel.org/pub/scm/linux/…

…kernel/git/tip/tip Pull x86 PIRQ updates from Thomas Gleixner: "A set of updates to support port 0x22/0x23 based PCI configuration space which can be found on various ALi chipsets and is also available on older Intel systems which expose a PIRQ router. While the Intel support is more or less nostalgia, the ALi chips are still in use on popular embedded boards used for routers" * tag 'x86-irq-2021-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix typo s/ECLR/ELCR/ for the PIC register x86: Avoid magic number with ELCR register accesses x86/PCI: Add support for the Intel 82426EX PIRQ router x86/PCI: Add support for the Intel 82374EB/82374SB (ESC) PIRQ router x86/PCI: Add support for the ALi M1487 (IBC) PIRQ router x86: Add support for 0x22/0x23 port I/O configuration space
ambv · Aug 30, 2021 · ccd8ec4 · ccd8ec4
2 parents 0a096f2 + 34739a2
commit ccd8ec4
Show file tree

Hide file tree

Showing 15 changed files with 359 additions and 37 deletions.
diff --git a/arch/x86/include/asm/i8259.h b/arch/x86/include/asm/i8259.h
@@ -19,6 +19,8 @@ extern unsigned int cached_irq_mask;
 #define PIC_MASTER_OCW3		PIC_MASTER_ISR
 #define PIC_SLAVE_CMD		0xa0
 #define PIC_SLAVE_IMR		0xa1
+#define PIC_ELCR1		0x4d0
+#define PIC_ELCR2		0x4d1
 
 /* i8259A PIC related value */
 #define PIC_CASCADE_IR		2

diff --git a/arch/x86/include/asm/pc-conf-reg.h b/arch/x86/include/asm/pc-conf-reg.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Support for the configuration register space at port I/O locations
+ * 0x22 and 0x23 variously used by PC architectures, e.g. the MP Spec,
+ * Cyrix CPUs, numerous chipsets.
+ */
+#ifndef _ASM_X86_PC_CONF_REG_H
+#define _ASM_X86_PC_CONF_REG_H
+
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#define PC_CONF_INDEX		0x22
+#define PC_CONF_DATA		0x23
+
+#define PC_CONF_MPS_IMCR	0x70
+
+extern raw_spinlock_t pc_conf_lock;
+
+static inline u8 pc_conf_get(u8 reg)
+{
+	outb(reg, PC_CONF_INDEX);
+	return inb(PC_CONF_DATA);
+}
+
+static inline void pc_conf_set(u8 reg, u8 data)
+{
+	outb(reg, PC_CONF_INDEX);
+	outb(data, PC_CONF_DATA);
+}
+
+#endif /* _ASM_X86_PC_CONF_REG_H */
diff --git a/arch/x86/include/asm/processor-cyrix.h b/arch/x86/include/asm/processor-cyrix.h
@@ -5,14 +5,14 @@
  * Access order is always 0x22 (=offset), 0x23 (=value)
  */
 
+#include <asm/pc-conf-reg.h>
+
 static inline u8 getCx86(u8 reg)
 {
-	outb(reg, 0x22);
-	return inb(0x23);
+	return pc_conf_get(reg);
 }
 
 static inline void setCx86(u8 reg, u8 data)
 {
-	outb(reg, 0x22);
-	outb(data, 0x23);
+	pc_conf_set(reg, data);
 }
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
@@ -558,10 +558,10 @@ acpi_parse_nmi_src(union acpi_subtable_headers * header, const unsigned long end
  * If a PIC-mode SCI is not recognized or gives spurious IRQ7's
  * it may require Edge Trigger -- use "acpi_sci=edge"
  *
- * Port 0x4d0-4d1 are ECLR1 and ECLR2, the Edge/Level Control Registers
+ * Port 0x4d0-4d1 are ELCR1 and ELCR2, the Edge/Level Control Registers
  * for the 8259 PIC.  bit[n] = 1 means irq[n] is Level, otherwise Edge.
- * ECLR1 is IRQs 0-7 (IRQ 0, 1, 2 must be 0)
- * ECLR2 is IRQs 8-15 (IRQ 8, 13 must be 0)
+ * ELCR1 is IRQs 0-7 (IRQ 0, 1, 2 must be 0)
+ * ELCR2 is IRQs 8-15 (IRQ 8, 13 must be 0)
  */
 
 void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
@@ -570,7 +570,7 @@ void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
 	unsigned int old, new;
 
 	/* Real old ELCR mask */
-	old = inb(0x4d0) | (inb(0x4d1) << 8);
+	old = inb(PIC_ELCR1) | (inb(PIC_ELCR2) << 8);
 
 	/*
 	 * If we use ACPI to set PCI IRQs, then we should clear ELCR
@@ -596,8 +596,8 @@ void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
 		return;
 
 	pr_warn("setting ELCR to %04x (from %04x)\n", new, old);
-	outb(new, 0x4d0);
-	outb(new >> 8, 0x4d1);
+	outb(new, PIC_ELCR1);
+	outb(new >> 8, PIC_ELCR2);
 }
 
 int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
@@ -38,6 +38,7 @@
 
 #include <asm/trace/irq_vectors.h>
 #include <asm/irq_remapping.h>
+#include <asm/pc-conf-reg.h>
 #include <asm/perf_event.h>
 #include <asm/x86_init.h>
 #include <linux/atomic.h>
@@ -132,18 +133,14 @@ static int enabled_via_apicbase __ro_after_init;
  */
 static inline void imcr_pic_to_apic(void)
 {
-	/* select IMCR register */
-	outb(0x70, 0x22);
 	/* NMI and 8259 INTR go through APIC */
-	outb(0x01, 0x23);
+	pc_conf_set(PC_CONF_MPS_IMCR, 0x01);
 }
 
 static inline void imcr_apic_to_pic(void)
 {
-	/* select IMCR register */
-	outb(0x70, 0x22);
 	/* NMI and 8259 INTR go directly to BSP */
-	outb(0x00, 0x23);
+	pc_conf_set(PC_CONF_MPS_IMCR, 0x00);
 }
 #endif
 

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
@@ -764,7 +764,7 @@ static bool irq_active_low(int idx)
 static bool EISA_ELCR(unsigned int irq)
 {
 	if (irq < nr_legacy_irqs()) {
-		unsigned int port = 0x4d0 + (irq >> 3);
+		unsigned int port = PIC_ELCR1 + (irq >> 3);
 		return (inb(port) >> (irq & 7)) & 1;
 	}
 	apic_printk(APIC_VERBOSE, KERN_INFO

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
@@ -1299,7 +1299,7 @@ static void __init print_PIC(void)
 
 	pr_debug("... PIC  ISR: %04x\n", v);
 
-	v = inb(0x4d1) << 8 | inb(0x4d0);
+	v = inb(PIC_ELCR2) << 8 | inb(PIC_ELCR1);
 	pr_debug("... PIC ELCR: %04x\n", v);
 }
 

diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c
@@ -235,15 +235,15 @@ static char irq_trigger[2];
  */
 static void restore_ELCR(char *trigger)
 {
-	outb(trigger[0], 0x4d0);
-	outb(trigger[1], 0x4d1);
+	outb(trigger[0], PIC_ELCR1);
+	outb(trigger[1], PIC_ELCR2);
 }
 
 static void save_ELCR(char *trigger)
 {
 	/* IRQ 0,1,2,8,13 are marked as reserved */
-	trigger[0] = inb(0x4d0) & 0xF8;
-	trigger[1] = inb(0x4d1) & 0xDE;
+	trigger[0] = inb(PIC_ELCR1) & 0xF8;
+	trigger[1] = inb(PIC_ELCR2) & 0xDE;
 }
 
 static void i8259A_resume(void)

diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
@@ -19,6 +19,7 @@
 #include <linux/smp.h>
 #include <linux/pci.h>
 
+#include <asm/i8259.h>
 #include <asm/io_apic.h>
 #include <asm/acpi.h>
 #include <asm/irqdomain.h>
@@ -251,7 +252,7 @@ static int __init ELCR_trigger(unsigned int irq)
 {
 	unsigned int port;
 
-	port = 0x4d0 + (irq >> 3);
+	port = PIC_ELCR1 + (irq >> 3);
 	return (inb(port) >> (irq & 7)) & 1;
 }
 

diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
@@ -541,17 +541,17 @@ static int picdev_slave_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
 			    addr, len, val);
 }
 
-static int picdev_eclr_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+static int picdev_elcr_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
 			     gpa_t addr, int len, const void *val)
 {
-	return picdev_write(container_of(dev, struct kvm_pic, dev_eclr),
+	return picdev_write(container_of(dev, struct kvm_pic, dev_elcr),
 			    addr, len, val);
 }
 
-static int picdev_eclr_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+static int picdev_elcr_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
 			    gpa_t addr, int len, void *val)
 {
-	return picdev_read(container_of(dev, struct kvm_pic, dev_eclr),
+	return picdev_read(container_of(dev, struct kvm_pic, dev_elcr),
 			    addr, len, val);
 }
 
@@ -577,9 +577,9 @@ static const struct kvm_io_device_ops picdev_slave_ops = {
 	.write    = picdev_slave_write,
 };
 
-static const struct kvm_io_device_ops picdev_eclr_ops = {
-	.read     = picdev_eclr_read,
-	.write    = picdev_eclr_write,
+static const struct kvm_io_device_ops picdev_elcr_ops = {
+	.read     = picdev_elcr_read,
+	.write    = picdev_elcr_write,
 };
 
 int kvm_pic_init(struct kvm *kvm)
@@ -602,7 +602,7 @@ int kvm_pic_init(struct kvm *kvm)
 	 */
 	kvm_iodevice_init(&s->dev_master, &picdev_master_ops);
 	kvm_iodevice_init(&s->dev_slave, &picdev_slave_ops);
-	kvm_iodevice_init(&s->dev_eclr, &picdev_eclr_ops);
+	kvm_iodevice_init(&s->dev_elcr, &picdev_elcr_ops);
 	mutex_lock(&kvm->slots_lock);
 	ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0x20, 2,
 				      &s->dev_master);
@@ -613,7 +613,7 @@ int kvm_pic_init(struct kvm *kvm)
 	if (ret < 0)
 		goto fail_unreg_2;
 
-	ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0x4d0, 2, &s->dev_eclr);
+	ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 0x4d0, 2, &s->dev_elcr);
 	if (ret < 0)
 		goto fail_unreg_1;
 
@@ -647,7 +647,7 @@ void kvm_pic_destroy(struct kvm *kvm)
 	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_master);
 	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_slave);
-	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_eclr);
+	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_elcr);
 	mutex_unlock(&kvm->slots_lock);
 
 	kvm->arch.vpic = NULL;

diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
@@ -55,7 +55,7 @@ struct kvm_pic {
 	int output;		/* intr from master PIC */
 	struct kvm_io_device dev_master;
 	struct kvm_io_device dev_slave;
-	struct kvm_io_device dev_eclr;
+	struct kvm_io_device dev_elcr;
 	void (*ack_notifier)(void *opaque, int irq);
 	unsigned long irq_states[PIC_NUM_PINS];
 };

diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o
 lib-y := delay.o misc.o cmdline.o cpu.o
 lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o
 lib-y += memcpy_$(BITS).o
+lib-y += pc-conf-reg.o
 lib-$(CONFIG_ARCH_HAS_COPY_MC) += copy_mc.o copy_mc_64.o
 lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o insn-eval.o
 lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o

diff --git a/arch/x86/lib/pc-conf-reg.c b/arch/x86/lib/pc-conf-reg.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for the configuration register space at port I/O locations
+ * 0x22 and 0x23 variously used by PC architectures, e.g. the MP Spec,
+ * Cyrix CPUs, numerous chipsets.  As the space is indirectly addressed
+ * it may have to be protected with a spinlock, depending on the context.
+ */
+
+#include <linux/spinlock.h>
+
+#include <asm/pc-conf-reg.h>
+
+DEFINE_RAW_SPINLOCK(pc_conf_lock);