File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/alpha/kernel/sys_mikasa.c b/arch/alpha/kernel/sys_mikasa.c
new file mode 100644
index 0000000..5e82dc1
--- /dev/null
+++ b/arch/alpha/kernel/sys_mikasa.c
@@ -0,0 +1,247 @@
+/*
+ *	linux/arch/alpha/kernel/sys_mikasa.c
+ *
+ *	Copyright (C) 1995 David A Rusling
+ *	Copyright (C) 1996 Jay A Estabrook
+ *	Copyright (C) 1998, 1999 Richard Henderson
+ *
+ * Code supporting the MIKASA (AlphaServer 1000).
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+
+#include <asm/ptrace.h>
+#include <asm/mce.h>
+#include <asm/dma.h>
+#include <asm/irq.h>
+#include <asm/mmu_context.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/core_apecs.h>
+#include <asm/core_cia.h>
+#include <asm/tlbflush.h>
+
+#include "proto.h"
+#include "irq_impl.h"
+#include "pci_impl.h"
+#include "machvec_impl.h"
+
+
+/* Note mask bit is true for ENABLED irqs.  */
+static int cached_irq_mask;
+
+static inline void
+mikasa_update_irq_hw(int mask)
+{
+	outw(mask, 0x536);
+}
+
+static inline void
+mikasa_enable_irq(struct irq_data *d)
+{
+	mikasa_update_irq_hw(cached_irq_mask |= 1 << (d->irq - 16));
+}
+
+static void
+mikasa_disable_irq(struct irq_data *d)
+{
+	mikasa_update_irq_hw(cached_irq_mask &= ~(1 << (d->irq - 16)));
+}
+
+static struct irq_chip mikasa_irq_type = {
+	.name		= "MIKASA",
+	.irq_unmask	= mikasa_enable_irq,
+	.irq_mask	= mikasa_disable_irq,
+	.irq_mask_ack	= mikasa_disable_irq,
+};
+
+static void 
+mikasa_device_interrupt(unsigned long vector)
+{
+	unsigned long pld;
+	unsigned int i;
+
+	/* Read the interrupt summary registers */
+	pld = (((~inw(0x534) & 0x0000ffffUL) << 16)
+	       | (((unsigned long) inb(0xa0)) << 8)
+	       | inb(0x20));
+
+	/*
+	 * Now for every possible bit set, work through them and call
+	 * the appropriate interrupt handler.
+	 */
+	while (pld) {
+		i = ffz(~pld);
+		pld &= pld - 1; /* clear least bit set */
+		if (i < 16) {
+			isa_device_interrupt(vector);
+		} else {
+			handle_irq(i);
+		}
+	}
+}
+
+static void __init
+mikasa_init_irq(void)
+{
+	long i;
+
+	if (alpha_using_srm)
+		alpha_mv.device_interrupt = srm_device_interrupt;
+
+	mikasa_update_irq_hw(0);
+
+	for (i = 16; i < 32; ++i) {
+		irq_set_chip_and_handler(i, &mikasa_irq_type,
+					 handle_level_irq);
+		irq_set_status_flags(i, IRQ_LEVEL);
+	}
+
+	init_i8259a_irqs();
+	common_init_isa_dma();
+}
+
+
+/*
+ * PCI Fixup configuration.
+ *
+ * Summary @ 0x536:
+ * Bit      Meaning
+ * 0        Interrupt Line A from slot 0
+ * 1        Interrupt Line B from slot 0
+ * 2        Interrupt Line C from slot 0
+ * 3        Interrupt Line D from slot 0
+ * 4        Interrupt Line A from slot 1
+ * 5        Interrupt line B from slot 1
+ * 6        Interrupt Line C from slot 1
+ * 7        Interrupt Line D from slot 1
+ * 8        Interrupt Line A from slot 2
+ * 9        Interrupt Line B from slot 2
+ *10        Interrupt Line C from slot 2
+ *11        Interrupt Line D from slot 2
+ *12        NCR 810 SCSI
+ *13        Power Supply Fail
+ *14        Temperature Warn
+ *15        Reserved
+ *
+ * The device to slot mapping looks like:
+ *
+ * Slot     Device
+ *  6       NCR SCSI controller
+ *  7       Intel PCI-EISA bridge chip
+ * 11       PCI on board slot 0
+ * 12       PCI on board slot 1
+ * 13       PCI on board slot 2
+ *   
+ *
+ * This two layered interrupt approach means that we allocate IRQ 16 and 
+ * above for PCI interrupts.  The IRQ relates to which bit the interrupt
+ * comes in on.  This makes interrupt processing much easier.
+ */
+
+static int __init
+mikasa_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	static char irq_tab[8][5] __initdata = {
+		/*INT    INTA   INTB   INTC   INTD */
+		{16+12, 16+12, 16+12, 16+12, 16+12},	/* IdSel 17,  SCSI */
+		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 18,  PCEB */
+		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 19,  ???? */
+		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 20,  ???? */
+		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 21,  ???? */
+		{ 16+0,  16+0,  16+1,  16+2,  16+3},	/* IdSel 22,  slot 0 */
+		{ 16+4,  16+4,  16+5,  16+6,  16+7},	/* IdSel 23,  slot 1 */
+		{ 16+8,  16+8,  16+9, 16+10, 16+11},	/* IdSel 24,  slot 2 */
+	};
+	const long min_idsel = 6, max_idsel = 13, irqs_per_slot = 5;
+	return COMMON_TABLE_LOOKUP;
+}
+
+
+#if defined(CONFIG_ALPHA_GENERIC) || !defined(CONFIG_ALPHA_PRIMO)
+static void
+mikasa_apecs_machine_check(unsigned long vector, unsigned long la_ptr)
+{
+#define MCHK_NO_DEVSEL 0x205U
+#define MCHK_NO_TABT 0x204U
+
+	struct el_common *mchk_header;
+	unsigned int code;
+
+	mchk_header = (struct el_common *)la_ptr;
+
+	/* Clear the error before any reporting.  */
+	mb();
+	mb(); /* magic */
+	draina();
+	apecs_pci_clr_err();
+	wrmces(0x7);
+	mb();
+
+	code = mchk_header->code;
+	process_mcheck_info(vector, la_ptr, "MIKASA APECS",
+			    (mcheck_expected(0)
+			     && (code == MCHK_NO_DEVSEL
+			         || code == MCHK_NO_TABT)));
+}
+#endif
+
+
+/*
+ * The System Vector
+ */
+
+#if defined(CONFIG_ALPHA_GENERIC) || !defined(CONFIG_ALPHA_PRIMO)
+struct alpha_machine_vector mikasa_mv __initmv = {
+	.vector_name		= "Mikasa",
+	DO_EV4_MMU,
+	DO_DEFAULT_RTC,
+	DO_APECS_IO,
+	.machine_check		= mikasa_apecs_machine_check,
+	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
+	.min_io_address		= DEFAULT_IO_BASE,
+	.min_mem_address	= APECS_AND_LCA_DEFAULT_MEM_BASE,
+
+	.nr_irqs		= 32,
+	.device_interrupt	= mikasa_device_interrupt,
+
+	.init_arch		= apecs_init_arch,
+	.init_irq		= mikasa_init_irq,
+	.init_rtc		= common_init_rtc,
+	.init_pci		= common_init_pci,
+	.pci_map_irq		= mikasa_map_irq,
+	.pci_swizzle		= common_swizzle,
+};
+ALIAS_MV(mikasa)
+#endif
+
+#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PRIMO)
+struct alpha_machine_vector mikasa_primo_mv __initmv = {
+	.vector_name		= "Mikasa-Primo",
+	DO_EV5_MMU,
+	DO_DEFAULT_RTC,
+	DO_CIA_IO,
+	.machine_check		= cia_machine_check,
+	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
+	.min_io_address		= DEFAULT_IO_BASE,
+	.min_mem_address	= CIA_DEFAULT_MEM_BASE,
+
+	.nr_irqs		= 32,
+	.device_interrupt	= mikasa_device_interrupt,
+
+	.init_arch		= cia_init_arch,
+	.init_irq		= mikasa_init_irq,
+	.init_rtc		= common_init_rtc,
+	.init_pci		= cia_init_pci,
+	.kill_arch		= cia_kill_arch,
+	.pci_map_irq		= mikasa_map_irq,
+	.pci_swizzle		= common_swizzle,
+};
+ALIAS_MV(mikasa_primo)
+#endif