ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/x86/kernel/i8259.c b/marvell/linux/arch/x86/kernel/i8259.c
new file mode 100644
index 0000000..8275362
--- /dev/null
+++ b/marvell/linux/arch/x86/kernel/i8259.c
@@ -0,0 +1,457 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/linkage.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/timex.h>
+#include <linux/random.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/syscore_ops.h>
+#include <linux/bitops.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+
+#include <linux/atomic.h>
+#include <asm/timer.h>
+#include <asm/hw_irq.h>
+#include <asm/pgtable.h>
+#include <asm/desc.h>
+#include <asm/apic.h>
+#include <asm/i8259.h>
+
+/*
+ * This is the 'legacy' 8259A Programmable Interrupt Controller,
+ * present in the majority of PC/AT boxes.
+ * plus some generic x86 specific things if generic specifics makes
+ * any sense at all.
+ */
+static void init_8259A(int auto_eoi);
+
+static bool pcat_compat __ro_after_init;
+static int i8259A_auto_eoi;
+DEFINE_RAW_SPINLOCK(i8259A_lock);
+
+/*
+ * 8259A PIC functions to handle ISA devices:
+ */
+
+/*
+ * This contains the irq mask for both 8259A irq controllers,
+ */
+unsigned int cached_irq_mask = 0xffff;
+
+/*
+ * Not all IRQs can be routed through the IO-APIC, eg. on certain (older)
+ * boards the timer interrupt is not really connected to any IO-APIC pin,
+ * it's fed to the master 8259A's IR0 line only.
+ *
+ * Any '1' bit in this mask means the IRQ is routed through the IO-APIC.
+ * this 'mixed mode' IRQ handling costs nothing because it's only used
+ * at IRQ setup time.
+ */
+unsigned long io_apic_irqs;
+
+static void mask_8259A_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << irq;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+ cached_irq_mask |= mask;
+ if (irq & 8)
+ outb(cached_slave_mask, PIC_SLAVE_IMR);
+ else
+ outb(cached_master_mask, PIC_MASTER_IMR);
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+static void disable_8259A_irq(struct irq_data *data)
+{
+ mask_8259A_irq(data->irq);
+}
+
+static void unmask_8259A_irq(unsigned int irq)
+{
+ unsigned int mask = ~(1 << irq);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+ cached_irq_mask &= mask;
+ if (irq & 8)
+ outb(cached_slave_mask, PIC_SLAVE_IMR);
+ else
+ outb(cached_master_mask, PIC_MASTER_IMR);
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+static void enable_8259A_irq(struct irq_data *data)
+{
+ unmask_8259A_irq(data->irq);
+}
+
+static int i8259A_irq_pending(unsigned int irq)
+{
+ unsigned int mask = 1<<irq;
+ unsigned long flags;
+ int ret;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+ if (irq < 8)
+ ret = inb(PIC_MASTER_CMD) & mask;
+ else
+ ret = inb(PIC_SLAVE_CMD) & (mask >> 8);
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+
+ return ret;
+}
+
+static void make_8259A_irq(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+ io_apic_irqs &= ~(1<<irq);
+ irq_set_chip_and_handler(irq, &i8259A_chip, handle_level_irq);
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ enable_irq(irq);
+ lapic_assign_legacy_vector(irq, true);
+}
+
+/*
+ * This function assumes to be called rarely. Switching between
+ * 8259A registers is slow.
+ * This has to be protected by the irq controller spinlock
+ * before being called.
+ */
+static inline int i8259A_irq_real(unsigned int irq)
+{
+ int value;
+ int irqmask = 1<<irq;
+
+ if (irq < 8) {
+ outb(0x0B, PIC_MASTER_CMD); /* ISR register */
+ value = inb(PIC_MASTER_CMD) & irqmask;
+ outb(0x0A, PIC_MASTER_CMD); /* back to the IRR register */
+ return value;
+ }
+ outb(0x0B, PIC_SLAVE_CMD); /* ISR register */
+ value = inb(PIC_SLAVE_CMD) & (irqmask >> 8);
+ outb(0x0A, PIC_SLAVE_CMD); /* back to the IRR register */
+ return value;
+}
+
+/*
+ * Careful! The 8259A is a fragile beast, it pretty
+ * much _has_ to be done exactly like this (mask it
+ * first, _then_ send the EOI, and the order of EOI
+ * to the two 8259s is important!
+ */
+static void mask_and_ack_8259A(struct irq_data *data)
+{
+ unsigned int irq = data->irq;
+ unsigned int irqmask = 1 << irq;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+ /*
+ * Lightweight spurious IRQ detection. We do not want
+ * to overdo spurious IRQ handling - it's usually a sign
+ * of hardware problems, so we only do the checks we can
+ * do without slowing down good hardware unnecessarily.
+ *
+ * Note that IRQ7 and IRQ15 (the two spurious IRQs
+ * usually resulting from the 8259A-1|2 PICs) occur
+ * even if the IRQ is masked in the 8259A. Thus we
+ * can check spurious 8259A IRQs without doing the
+ * quite slow i8259A_irq_real() call for every IRQ.
+ * This does not cover 100% of spurious interrupts,
+ * but should be enough to warn the user that there
+ * is something bad going on ...
+ */
+ if (cached_irq_mask & irqmask)
+ goto spurious_8259A_irq;
+ cached_irq_mask |= irqmask;
+
+handle_real_irq:
+ if (irq & 8) {
+ inb(PIC_SLAVE_IMR); /* DUMMY - (do we need this?) */
+ outb(cached_slave_mask, PIC_SLAVE_IMR);
+ /* 'Specific EOI' to slave */
+ outb(0x60+(irq&7), PIC_SLAVE_CMD);
+ /* 'Specific EOI' to master-IRQ2 */
+ outb(0x60+PIC_CASCADE_IR, PIC_MASTER_CMD);
+ } else {
+ inb(PIC_MASTER_IMR); /* DUMMY - (do we need this?) */
+ outb(cached_master_mask, PIC_MASTER_IMR);
+ outb(0x60+irq, PIC_MASTER_CMD); /* 'Specific EOI to master */
+ }
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+ return;
+
+spurious_8259A_irq:
+ /*
+ * this is the slow path - should happen rarely.
+ */
+ if (i8259A_irq_real(irq))
+ /*
+ * oops, the IRQ _is_ in service according to the
+ * 8259A - not spurious, go handle it.
+ */
+ goto handle_real_irq;
+
+ {
+ static int spurious_irq_mask;
+ /*
+ * At this point we can be sure the IRQ is spurious,
+ * lets ACK and report it. [once per IRQ]
+ */
+ if (!(spurious_irq_mask & irqmask)) {
+ printk_deferred(KERN_DEBUG
+ "spurious 8259A interrupt: IRQ%d.\n", irq);
+ spurious_irq_mask |= irqmask;
+ }
+ atomic_inc(&irq_err_count);
+ /*
+ * Theoretically we do not have to handle this IRQ,
+ * but in Linux this does not cause problems and is
+ * simpler for us.
+ */
+ goto handle_real_irq;
+ }
+}
+
+struct irq_chip i8259A_chip = {
+ .name = "XT-PIC",
+ .irq_mask = disable_8259A_irq,
+ .irq_disable = disable_8259A_irq,
+ .irq_unmask = enable_8259A_irq,
+ .irq_mask_ack = mask_and_ack_8259A,
+};
+
+static char irq_trigger[2];
+/**
+ * ELCR registers (0x4d0, 0x4d1) control edge/level of IRQ
+ */
+static void restore_ELCR(char *trigger)
+{
+ outb(trigger[0], 0x4d0);
+ outb(trigger[1], 0x4d1);
+}
+
+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;
+}
+
+static void i8259A_resume(void)
+{
+ init_8259A(i8259A_auto_eoi);
+ restore_ELCR(irq_trigger);
+}
+
+static int i8259A_suspend(void)
+{
+ save_ELCR(irq_trigger);
+ return 0;
+}
+
+static void i8259A_shutdown(void)
+{
+ /* Put the i8259A into a quiescent state that
+ * the kernel initialization code can get it
+ * out of.
+ */
+ outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */
+ outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
+}
+
+static struct syscore_ops i8259_syscore_ops = {
+ .suspend = i8259A_suspend,
+ .resume = i8259A_resume,
+ .shutdown = i8259A_shutdown,
+};
+
+static void mask_8259A(void)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+
+ outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */
+ outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
+
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+static void unmask_8259A(void)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+
+ outb(cached_master_mask, PIC_MASTER_IMR); /* restore master IRQ mask */
+ outb(cached_slave_mask, PIC_SLAVE_IMR); /* restore slave IRQ mask */
+
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+static int probe_8259A(void)
+{
+ unsigned char new_val, probe_val = ~(1 << PIC_CASCADE_IR);
+ unsigned long flags;
+
+ /*
+ * If MADT has the PCAT_COMPAT flag set, then do not bother probing
+ * for the PIC. Some BIOSes leave the PIC uninitialized and probing
+ * fails.
+ *
+ * Right now this causes problems as quite some code depends on
+ * nr_legacy_irqs() > 0 or has_legacy_pic() == true. This is silly
+ * when the system has an IO/APIC because then PIC is not required
+ * at all, except for really old machines where the timer interrupt
+ * must be routed through the PIC. So just pretend that the PIC is
+ * there and let legacy_pic->init() initialize it for nothing.
+ *
+ * Alternatively this could just try to initialize the PIC and
+ * repeat the probe, but for cases where there is no PIC that's
+ * just pointless.
+ */
+ if (pcat_compat)
+ return nr_legacy_irqs();
+
+ /*
+ * Check to see if we have a PIC. Mask all except the cascade and
+ * read back the value we just wrote. If we don't have a PIC, we
+ * will read 0xff as opposed to the value we wrote.
+ */
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+
+ outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
+ outb(probe_val, PIC_MASTER_IMR);
+ new_val = inb(PIC_MASTER_IMR);
+ if (new_val != probe_val) {
+ printk(KERN_INFO "Using NULL legacy PIC\n");
+ legacy_pic = &null_legacy_pic;
+ }
+
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+ return nr_legacy_irqs();
+}
+
+static void init_8259A(int auto_eoi)
+{
+ unsigned long flags;
+
+ i8259A_auto_eoi = auto_eoi;
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+
+ outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */
+
+ /*
+ * outb_pic - this has to work on a wide range of PC hardware.
+ */
+ outb_pic(0x11, PIC_MASTER_CMD); /* ICW1: select 8259A-1 init */
+
+ /* ICW2: 8259A-1 IR0-7 mapped to ISA_IRQ_VECTOR(0) */
+ outb_pic(ISA_IRQ_VECTOR(0), PIC_MASTER_IMR);
+
+ /* 8259A-1 (the master) has a slave on IR2 */
+ outb_pic(1U << PIC_CASCADE_IR, PIC_MASTER_IMR);
+
+ if (auto_eoi) /* master does Auto EOI */
+ outb_pic(MASTER_ICW4_DEFAULT | PIC_ICW4_AEOI, PIC_MASTER_IMR);
+ else /* master expects normal EOI */
+ outb_pic(MASTER_ICW4_DEFAULT, PIC_MASTER_IMR);
+
+ outb_pic(0x11, PIC_SLAVE_CMD); /* ICW1: select 8259A-2 init */
+
+ /* ICW2: 8259A-2 IR0-7 mapped to ISA_IRQ_VECTOR(8) */
+ outb_pic(ISA_IRQ_VECTOR(8), PIC_SLAVE_IMR);
+ /* 8259A-2 is a slave on master's IR2 */
+ outb_pic(PIC_CASCADE_IR, PIC_SLAVE_IMR);
+ /* (slave's support for AEOI in flat mode is to be investigated) */
+ outb_pic(SLAVE_ICW4_DEFAULT, PIC_SLAVE_IMR);
+
+ if (auto_eoi)
+ /*
+ * In AEOI mode we just have to mask the interrupt
+ * when acking.
+ */
+ i8259A_chip.irq_mask_ack = disable_8259A_irq;
+ else
+ i8259A_chip.irq_mask_ack = mask_and_ack_8259A;
+
+ udelay(100); /* wait for 8259A to initialize */
+
+ outb(cached_master_mask, PIC_MASTER_IMR); /* restore master IRQ mask */
+ outb(cached_slave_mask, PIC_SLAVE_IMR); /* restore slave IRQ mask */
+
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+/*
+ * make i8259 a driver so that we can select pic functions at run time. the goal
+ * is to make x86 binary compatible among pc compatible and non-pc compatible
+ * platforms, such as x86 MID.
+ */
+
+static void legacy_pic_noop(void) { };
+static void legacy_pic_uint_noop(unsigned int unused) { };
+static void legacy_pic_int_noop(int unused) { };
+static int legacy_pic_irq_pending_noop(unsigned int irq)
+{
+ return 0;
+}
+static int legacy_pic_probe(void)
+{
+ return 0;
+}
+
+struct legacy_pic null_legacy_pic = {
+ .nr_legacy_irqs = 0,
+ .chip = &dummy_irq_chip,
+ .mask = legacy_pic_uint_noop,
+ .unmask = legacy_pic_uint_noop,
+ .mask_all = legacy_pic_noop,
+ .restore_mask = legacy_pic_noop,
+ .init = legacy_pic_int_noop,
+ .probe = legacy_pic_probe,
+ .irq_pending = legacy_pic_irq_pending_noop,
+ .make_irq = legacy_pic_uint_noop,
+};
+
+struct legacy_pic default_legacy_pic = {
+ .nr_legacy_irqs = NR_IRQS_LEGACY,
+ .chip = &i8259A_chip,
+ .mask = mask_8259A_irq,
+ .unmask = unmask_8259A_irq,
+ .mask_all = mask_8259A,
+ .restore_mask = unmask_8259A,
+ .init = init_8259A,
+ .probe = probe_8259A,
+ .irq_pending = i8259A_irq_pending,
+ .make_irq = make_8259A_irq,
+};
+
+struct legacy_pic *legacy_pic = &default_legacy_pic;
+EXPORT_SYMBOL(legacy_pic);
+
+static int __init i8259A_init_ops(void)
+{
+ if (legacy_pic == &default_legacy_pic)
+ register_syscore_ops(&i8259_syscore_ops);
+
+ return 0;
+}
+device_initcall(i8259A_init_ops);
+
+void __init legacy_pic_pcat_compat(void)
+{
+ pcat_compat = true;
+}