16 files changed, 1223 insertions, 0 deletions
diff --git a/arch/mips/include/asm/dec/ecc.h b/arch/mips/include/asm/dec/ecc.h
new file mode 100644
index 000000000..c3a3f71f1
--- /dev/null
+++ b/arch/mips/include/asm/dec/ecc.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/ecc.h
+ *
+ *	ECC handling logic definitions common to DECstation/DECsystem
+ *	5000/200 (KN02), 5000/240 (KN03), 5000/260 (KN05) and
+ *	DECsystem 5900 (KN03), 5900/260 (KN05) systems.
+ *
+ *	Copyright (C) 2003  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_ECC_H
+#define __ASM_MIPS_DEC_ECC_H
+
+/*
+ * Error Address Register bits.
+ * The register is r/wc -- any write clears it.
+ */
+#define KN0X_EAR_VALID		(1<<31)		/* error data valid, bus IRQ */
+#define KN0X_EAR_CPU		(1<<30)		/* CPU/DMA transaction */
+#define KN0X_EAR_WRITE		(1<<29)		/* write/read transaction */
+#define KN0X_EAR_ECCERR		(1<<28)		/* ECC/timeout or overrun */
+#define KN0X_EAR_RES_27		(1<<27)		/* unused */
+#define KN0X_EAR_ADDRESS	(0x7ffffff<<0)	/* address involved */
+
+/*
+ * Error Syndrome Register bits.
+ * The register is frozen when EAR.VALID is set, otherwise it records bits
+ * from the last memory read.  The register is r/wc -- any write clears it.
+ */
+#define KN0X_ESR_VLDHI		(1<<31)		/* error data valid hi word */
+#define KN0X_ESR_CHKHI		(0x7f<<24)	/* check bits read from mem */
+#define KN0X_ESR_SNGHI		(1<<23)		/* single/double bit error */
+#define KN0X_ESR_SYNHI		(0x7f<<16)	/* syndrome from ECC logic */
+#define KN0X_ESR_VLDLO		(1<<15)		/* error data valid lo word */
+#define KN0X_ESR_CHKLO		(0x7f<<8)	/* check bits read from mem */
+#define KN0X_ESR_SNGLO		(1<<7)		/* single/double bit error */
+#define KN0X_ESR_SYNLO		(0x7f<<0)	/* syndrome from ECC logic */
+
+
+#ifndef __ASSEMBLY__
+
+#include <linux/interrupt.h>
+
+struct pt_regs;
+
+extern void dec_ecc_be_init(void);
+extern int dec_ecc_be_handler(struct pt_regs *regs, int is_fixup);
+extern irqreturn_t dec_ecc_be_interrupt(int irq, void *dev_id);
+#endif
+
+#endif /* __ASM_MIPS_DEC_ECC_H */
diff --git a/arch/mips/include/asm/dec/interrupts.h b/arch/mips/include/asm/dec/interrupts.h
new file mode 100644
index 000000000..e10d34106
--- /dev/null
+++ b/arch/mips/include/asm/dec/interrupts.h
@@ -0,0 +1,126 @@
+/*
+ * Miscellaneous definitions used to initialise the interrupt vector table
+ * with the machine-specific interrupt routines.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1997 by Paul M. Antoine.
+ * reworked 1998 by Harald Koerfgen.
+ * Copyright (C) 2001, 2002, 2003  Maciej W. Rozycki
+ */
+
+#ifndef __ASM_DEC_INTERRUPTS_H
+#define __ASM_DEC_INTERRUPTS_H
+
+#include <irq.h>
+#include <asm/mipsregs.h>
+
+
+/*
+ * The list of possible system devices which provide an
+ * interrupt.  Not all devices exist on a given system.
+ */
+#define DEC_IRQ_CASCADE		0	/* cascade from CSR or I/O ASIC */
+
+/* Ordinary interrupts */
+#define DEC_IRQ_AB_RECV		1	/* ACCESS.bus receive */
+#define DEC_IRQ_AB_XMIT		2	/* ACCESS.bus transmit */
+#define DEC_IRQ_DZ11		3	/* DZ11 (DC7085) serial */
+#define DEC_IRQ_ASC		4	/* ASC (NCR53C94) SCSI */
+#define DEC_IRQ_FLOPPY		5	/* 82077 FDC */
+#define DEC_IRQ_FPU		6	/* R3k FPU */
+#define DEC_IRQ_HALT		7	/* HALT button or from ACCESS.Bus */
+#define DEC_IRQ_ISDN		8	/* Am79C30A ISDN */
+#define DEC_IRQ_LANCE		9	/* LANCE (Am7990) Ethernet */
+#define DEC_IRQ_BUS		10	/* memory, I/O bus read/write errors */
+#define DEC_IRQ_PSU		11	/* power supply unit warning */
+#define DEC_IRQ_RTC		12	/* DS1287 RTC */
+#define DEC_IRQ_SCC0		13	/* SCC (Z85C30) serial #0 */
+#define DEC_IRQ_SCC1		14	/* SCC (Z85C30) serial #1 */
+#define DEC_IRQ_SII		15	/* SII (DC7061) SCSI */
+#define DEC_IRQ_TC0		16	/* TURBOchannel slot #0 */
+#define DEC_IRQ_TC1		17	/* TURBOchannel slot #1 */
+#define DEC_IRQ_TC2		18	/* TURBOchannel slot #2 */
+#define DEC_IRQ_TIMER		19	/* ARC periodic timer */
+#define DEC_IRQ_VIDEO		20	/* framebuffer */
+
+/* I/O ASIC DMA interrupts */
+#define DEC_IRQ_ASC_MERR	21	/* ASC memory read error */
+#define DEC_IRQ_ASC_ERR		22	/* ASC page overrun */
+#define DEC_IRQ_ASC_DMA		23	/* ASC buffer pointer loaded */
+#define DEC_IRQ_FLOPPY_ERR	24	/* FDC error */
+#define DEC_IRQ_ISDN_ERR	25	/* ISDN memory read/overrun error */
+#define DEC_IRQ_ISDN_RXDMA	26	/* ISDN recv buffer pointer loaded */
+#define DEC_IRQ_ISDN_TXDMA	27	/* ISDN xmit buffer pointer loaded */
+#define DEC_IRQ_LANCE_MERR	28	/* LANCE memory read error */
+#define DEC_IRQ_SCC0A_RXERR	29	/* SCC0A (printer) receive overrun */
+#define DEC_IRQ_SCC0A_RXDMA	30	/* SCC0A receive half page */
+#define DEC_IRQ_SCC0A_TXERR	31	/* SCC0A xmit memory read/overrun */
+#define DEC_IRQ_SCC0A_TXDMA	32	/* SCC0A transmit page end */
+#define DEC_IRQ_AB_RXERR	33	/* ACCESS.bus receive overrun */
+#define DEC_IRQ_AB_RXDMA	34	/* ACCESS.bus receive half page */
+#define DEC_IRQ_AB_TXERR	35	/* ACCESS.bus xmit memory read/ovrn */
+#define DEC_IRQ_AB_TXDMA	36	/* ACCESS.bus transmit page end */
+#define DEC_IRQ_SCC1A_RXERR	37	/* SCC1A (modem) receive overrun */
+#define DEC_IRQ_SCC1A_RXDMA	38	/* SCC1A receive half page */
+#define DEC_IRQ_SCC1A_TXERR	39	/* SCC1A xmit memory read/overrun */
+#define DEC_IRQ_SCC1A_TXDMA	40	/* SCC1A transmit page end */
+
+/* TC5 & TC6 are virtual slots for KN02's onboard devices */
+#define DEC_IRQ_TC5		DEC_IRQ_ASC	/* virtual PMAZ-AA */
+#define DEC_IRQ_TC6		DEC_IRQ_LANCE	/* virtual PMAD-AA */
+
+#define DEC_NR_INTS		41
+
+
+/* Largest of cpu mask_nr tables. */
+#define DEC_MAX_CPU_INTS	6
+/* Largest of asic mask_nr tables. */
+#define DEC_MAX_ASIC_INTS	9
+
+
+/*
+ * CPU interrupt bits common to all systems.
+ */
+#define DEC_CPU_INR_FPU		7	/* R3k FPU */
+#define DEC_CPU_INR_SW1		1	/* software #1 */
+#define DEC_CPU_INR_SW0		0	/* software #0 */
+
+#define DEC_CPU_IRQ_BASE	MIPS_CPU_IRQ_BASE	/* first IRQ assigned to CPU */
+
+#define DEC_CPU_IRQ_NR(n)	((n) + DEC_CPU_IRQ_BASE)
+#define DEC_CPU_IRQ_MASK(n)	(1 << ((n) + CAUSEB_IP))
+#define DEC_CPU_IRQ_ALL		(0xff << CAUSEB_IP)
+
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Interrupt table structures to hide differences between systems.
+ */
+typedef union { int i; void *p; } int_ptr;
+extern int dec_interrupt[DEC_NR_INTS];
+extern int_ptr cpu_mask_nr_tbl[DEC_MAX_CPU_INTS][2];
+extern int_ptr asic_mask_nr_tbl[DEC_MAX_ASIC_INTS][2];
+extern int cpu_fpu_mask;
+
+
+/*
+ * Common interrupt routine prototypes for all DECStations
+ */
+extern void kn02_io_int(void);
+extern void kn02xa_io_int(void);
+extern void kn03_io_int(void);
+extern void asic_dma_int(void);
+extern void asic_all_int(void);
+extern void kn02_all_int(void);
+extern void cpu_all_int(void);
+
+extern void dec_intr_unimplemented(void);
+extern void asic_intr_unimplemented(void);
+
+#endif /* __ASSEMBLY__ */
+
+#endif
diff --git a/arch/mips/include/asm/dec/ioasic.h b/arch/mips/include/asm/dec/ioasic.h
new file mode 100644
index 000000000..6d912f095
--- /dev/null
+++ b/arch/mips/include/asm/dec/ioasic.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/ioasic.h
+ *
+ *	DEC I/O ASIC access operations.
+ *
+ *	Copyright (C) 2000, 2002, 2003  Maciej W. Rozycki
+ */
+
+#ifndef __ASM_DEC_IOASIC_H
+#define __ASM_DEC_IOASIC_H
+
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+extern spinlock_t ioasic_ssr_lock;
+
+extern volatile u32 *ioasic_base;
+
+static inline void ioasic_write(unsigned int reg, u32 v)
+{
+	ioasic_base[reg / 4] = v;
+}
+
+static inline u32 ioasic_read(unsigned int reg)
+{
+	return ioasic_base[reg / 4];
+}
+
+extern void init_ioasic_irqs(int base);
+
+extern int dec_ioasic_clocksource_init(void);
+
+#endif /* __ASM_DEC_IOASIC_H */
diff --git a/arch/mips/include/asm/dec/ioasic_addrs.h b/arch/mips/include/asm/dec/ioasic_addrs.h
new file mode 100644
index 000000000..8bd95971f
--- /dev/null
+++ b/arch/mips/include/asm/dec/ioasic_addrs.h
@@ -0,0 +1,152 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Definitions for the address map in the JUNKIO Asic
+ *
+ * Created with Information from:
+ *
+ * "DEC 3000 300/400/500/600/700/800/900 AXP Models System Programmer's Manual"
+ *
+ * and the Mach Sources
+ *
+ * Copyright (C) 199x  the Anonymous
+ * Copyright (C) 2002, 2003  Maciej W. Rozycki
+ */
+
+#ifndef __ASM_MIPS_DEC_IOASIC_ADDRS_H
+#define __ASM_MIPS_DEC_IOASIC_ADDRS_H
+
+#define IOASIC_SLOT_SIZE 0x00040000
+
+/*
+ * Address ranges decoded by the I/O ASIC for onboard devices.
+ */
+#define IOASIC_SYS_ROM	(0*IOASIC_SLOT_SIZE)	/* system board ROM */
+#define IOASIC_IOCTL	(1*IOASIC_SLOT_SIZE)	/* I/O ASIC */
+#define IOASIC_ESAR	(2*IOASIC_SLOT_SIZE)	/* LANCE MAC address chip */
+#define IOASIC_LANCE	(3*IOASIC_SLOT_SIZE)	/* LANCE Ethernet */
+#define IOASIC_SCC0	(4*IOASIC_SLOT_SIZE)	/* SCC #0 */
+#define IOASIC_VDAC_HI	(5*IOASIC_SLOT_SIZE)	/* VDAC (maxine) */
+#define IOASIC_SCC1	(6*IOASIC_SLOT_SIZE)	/* SCC #1 (3min, 3max+) */
+#define IOASIC_VDAC_LO	(7*IOASIC_SLOT_SIZE)	/* VDAC (maxine) */
+#define IOASIC_TOY	(8*IOASIC_SLOT_SIZE)	/* RTC */
+#define IOASIC_ISDN	(9*IOASIC_SLOT_SIZE)	/* ISDN (maxine) */
+#define IOASIC_ERRADDR	(9*IOASIC_SLOT_SIZE)	/* bus error address (3max+) */
+#define IOASIC_CHKSYN	(10*IOASIC_SLOT_SIZE)	/* ECC syndrome (3max+) */
+#define IOASIC_ACC_BUS	(10*IOASIC_SLOT_SIZE)	/* ACCESS.bus (maxine) */
+#define IOASIC_MCR	(11*IOASIC_SLOT_SIZE)	/* memory control (3max+) */
+#define IOASIC_FLOPPY	(11*IOASIC_SLOT_SIZE)	/* FDC (maxine) */
+#define IOASIC_SCSI	(12*IOASIC_SLOT_SIZE)	/* ASC SCSI */
+#define IOASIC_FDC_DMA	(13*IOASIC_SLOT_SIZE)	/* FDC DMA (maxine) */
+#define IOASIC_SCSI_DMA	(14*IOASIC_SLOT_SIZE)	/* ??? */
+#define IOASIC_RES_15	(15*IOASIC_SLOT_SIZE)	/* unused? */
+
+
+/*
+ * Offsets for I/O ASIC registers
+ * (relative to (dec_kn_slot_base + IOASIC_IOCTL)).
+ */
+					/* all systems */
+#define IO_REG_SCSI_DMA_P	0x00	/* SCSI DMA Pointer */
+#define IO_REG_SCSI_DMA_BP	0x10	/* SCSI DMA Buffer Pointer */
+#define IO_REG_LANCE_DMA_P	0x20	/* LANCE DMA Pointer */
+#define IO_REG_SCC0A_T_DMA_P	0x30	/* SCC0A Transmit DMA Pointer */
+#define IO_REG_SCC0A_R_DMA_P	0x40	/* SCC0A Receive DMA Pointer */
+
+					/* except Maxine */
+#define IO_REG_SCC1A_T_DMA_P	0x50	/* SCC1A Transmit DMA Pointer */
+#define IO_REG_SCC1A_R_DMA_P	0x60	/* SCC1A Receive DMA Pointer */
+
+					/* Maxine */
+#define IO_REG_AB_T_DMA_P	0x50	/* ACCESS.bus Transmit DMA Pointer */
+#define IO_REG_AB_R_DMA_P	0x60	/* ACCESS.bus Receive DMA Pointer */
+#define IO_REG_FLOPPY_DMA_P	0x70	/* Floppy DMA Pointer */
+#define IO_REG_ISDN_T_DMA_P	0x80	/* ISDN Transmit DMA Pointer */
+#define IO_REG_ISDN_T_DMA_BP	0x90	/* ISDN Transmit DMA Buffer Pointer */
+#define IO_REG_ISDN_R_DMA_P	0xa0	/* ISDN Receive DMA Pointer */
+#define IO_REG_ISDN_R_DMA_BP	0xb0	/* ISDN Receive DMA Buffer Pointer */
+
+					/* all systems */
+#define IO_REG_DATA_0		0xc0	/* System Data Buffer 0 */
+#define IO_REG_DATA_1		0xd0	/* System Data Buffer 1 */
+#define IO_REG_DATA_2		0xe0	/* System Data Buffer 2 */
+#define IO_REG_DATA_3		0xf0	/* System Data Buffer 3 */
+
+					/* all systems */
+#define IO_REG_SSR		0x100	/* System Support Register */
+#define IO_REG_SIR		0x110	/* System Interrupt Register */
+#define IO_REG_SIMR		0x120	/* System Interrupt Mask Reg. */
+#define IO_REG_SAR		0x130	/* System Address Register */
+
+					/* Maxine */
+#define IO_REG_ISDN_T_DATA	0x140	/* ISDN Xmit Data Register */
+#define IO_REG_ISDN_R_DATA	0x150	/* ISDN Receive Data Register */
+
+					/* all systems */
+#define IO_REG_LANCE_SLOT	0x160	/* LANCE I/O Slot Register */
+#define IO_REG_SCSI_SLOT	0x170	/* SCSI Slot Register */
+#define IO_REG_SCC0A_SLOT	0x180	/* SCC0A DMA Slot Register */
+
+					/* except Maxine */
+#define IO_REG_SCC1A_SLOT	0x190	/* SCC1A DMA Slot Register */
+
+					/* Maxine */
+#define IO_REG_AB_SLOT		0x190	/* ACCESS.bus DMA Slot Register */
+#define IO_REG_FLOPPY_SLOT	0x1a0	/* Floppy Slot Register */
+
+					/* all systems */
+#define IO_REG_SCSI_SCR		0x1b0	/* SCSI Partial-Word DMA Control */
+#define IO_REG_SCSI_SDR0	0x1c0	/* SCSI DMA Partial Word 0 */
+#define IO_REG_SCSI_SDR1	0x1d0	/* SCSI DMA Partial Word 1 */
+#define IO_REG_FCTR		0x1e0	/* Free-Running Counter */
+#define IO_REG_RES_31		0x1f0	/* unused */
+
+
+/*
+ * The upper 16 bits of the System Support Register are a part of the
+ * I/O ASIC's internal DMA engine and thus are common to all I/O ASIC
+ * machines.  The exception is the Maxine, which makes use of the
+ * FLOPPY and ISDN bits (otherwise unused) and has a different SCC
+ * wiring.
+ */
+						/* all systems */
+#define IO_SSR_SCC0A_TX_DMA_EN	(1<<31)		/* SCC0A transmit DMA enable */
+#define IO_SSR_SCC0A_RX_DMA_EN	(1<<30)		/* SCC0A receive DMA enable */
+#define IO_SSR_RES_27		(1<<27)		/* unused */
+#define IO_SSR_RES_26		(1<<26)		/* unused */
+#define IO_SSR_RES_25		(1<<25)		/* unused */
+#define IO_SSR_RES_24		(1<<24)		/* unused */
+#define IO_SSR_RES_23		(1<<23)		/* unused */
+#define IO_SSR_SCSI_DMA_DIR	(1<<18)		/* SCSI DMA direction */
+#define IO_SSR_SCSI_DMA_EN	(1<<17)		/* SCSI DMA enable */
+#define IO_SSR_LANCE_DMA_EN	(1<<16)		/* LANCE DMA enable */
+
+						/* except Maxine */
+#define IO_SSR_SCC1A_TX_DMA_EN	(1<<29)		/* SCC1A transmit DMA enable */
+#define IO_SSR_SCC1A_RX_DMA_EN	(1<<28)		/* SCC1A receive DMA enable */
+#define IO_SSR_RES_22		(1<<22)		/* unused */
+#define IO_SSR_RES_21		(1<<21)		/* unused */
+#define IO_SSR_RES_20		(1<<20)		/* unused */
+#define IO_SSR_RES_19		(1<<19)		/* unused */
+
+						/* Maxine */
+#define IO_SSR_AB_TX_DMA_EN	(1<<29)		/* ACCESS.bus xmit DMA enable */
+#define IO_SSR_AB_RX_DMA_EN	(1<<28)		/* ACCESS.bus recv DMA enable */
+#define IO_SSR_FLOPPY_DMA_DIR	(1<<22)		/* Floppy DMA direction */
+#define IO_SSR_FLOPPY_DMA_EN	(1<<21)		/* Floppy DMA enable */
+#define IO_SSR_ISDN_TX_DMA_EN	(1<<20)		/* ISDN transmit DMA enable */
+#define IO_SSR_ISDN_RX_DMA_EN	(1<<19)		/* ISDN receive DMA enable */
+
+/*
+ * The lower 16 bits are system-specific.  Bits 15,11:8 are common and
+ * defined here.  The rest is defined in system-specific headers.
+ */
+#define KN0X_IO_SSR_DIAGDN	(1<<15)		/* diagnostic jumper */
+#define KN0X_IO_SSR_SCC_RST	(1<<11)		/* ~SCC0,1 (Z85C30) reset */
+#define KN0X_IO_SSR_RTC_RST	(1<<10)		/* ~RTC (DS1287) reset */
+#define KN0X_IO_SSR_ASC_RST	(1<<9)		/* ~ASC (NCR53C94) reset */
+#define KN0X_IO_SSR_LANCE_RST	(1<<8)		/* ~LANCE (Am7990) reset */
+
+#endif /* __ASM_MIPS_DEC_IOASIC_ADDRS_H */
diff --git a/arch/mips/include/asm/dec/ioasic_ints.h b/arch/mips/include/asm/dec/ioasic_ints.h
new file mode 100644
index 000000000..9aaa98696
--- /dev/null
+++ b/arch/mips/include/asm/dec/ioasic_ints.h
@@ -0,0 +1,74 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Definitions for the interrupt related bits in the I/O ASIC
+ * interrupt status register (and the interrupt mask register, of course)
+ *
+ * Created with Information from:
+ *
+ * "DEC 3000 300/400/500/600/700/800/900 AXP Models System Programmer's Manual"
+ *
+ * and the Mach Sources
+ *
+ * Copyright (C) 199x  the Anonymous
+ * Copyright (C) 2002  Maciej W. Rozycki
+ */
+
+#ifndef __ASM_DEC_IOASIC_INTS_H
+#define __ASM_DEC_IOASIC_INTS_H
+
+/*
+ * The upper 16 bits are a part of the I/O ASIC's internal DMA engine
+ * and thus are common to all I/O ASIC machines.  The exception is
+ * the Maxine, which makes use of the FLOPPY and ISDN bits (otherwise
+ * unused) and has a different SCC wiring.
+ */
+					/* all systems */
+#define IO_INR_SCC0A_TXDMA	31	/* SCC0A transmit page end */
+#define IO_INR_SCC0A_TXERR	30	/* SCC0A transmit memory read error */
+#define IO_INR_SCC0A_RXDMA	29	/* SCC0A receive half page */
+#define IO_INR_SCC0A_RXERR	28	/* SCC0A receive overrun */
+#define IO_INR_ASC_DMA		19	/* ASC buffer pointer loaded */
+#define IO_INR_ASC_ERR		18	/* ASC page overrun */
+#define IO_INR_ASC_MERR		17	/* ASC memory read error */
+#define IO_INR_LANCE_MERR	16	/* LANCE memory read error */
+
+					/* except Maxine */
+#define IO_INR_SCC1A_TXDMA	27	/* SCC1A transmit page end */
+#define IO_INR_SCC1A_TXERR	26	/* SCC1A transmit memory read error */
+#define IO_INR_SCC1A_RXDMA	25	/* SCC1A receive half page */
+#define IO_INR_SCC1A_RXERR	24	/* SCC1A receive overrun */
+#define IO_INR_RES_23		23	/* unused */
+#define IO_INR_RES_22		22	/* unused */
+#define IO_INR_RES_21		21	/* unused */
+#define IO_INR_RES_20		20	/* unused */
+
+					/* Maxine */
+#define IO_INR_AB_TXDMA		27	/* ACCESS.bus transmit page end */
+#define IO_INR_AB_TXERR		26	/* ACCESS.bus xmit memory read error */
+#define IO_INR_AB_RXDMA		25	/* ACCESS.bus receive half page */
+#define IO_INR_AB_RXERR		24	/* ACCESS.bus receive overrun */
+#define IO_INR_FLOPPY_ERR	23	/* FDC error */
+#define IO_INR_ISDN_TXDMA	22	/* ISDN xmit buffer pointer loaded */
+#define IO_INR_ISDN_RXDMA	21	/* ISDN recv buffer pointer loaded */
+#define IO_INR_ISDN_ERR		20	/* ISDN memory read/overrun error */
+
+#define IO_INR_DMA		16	/* first DMA IRQ */
+
+/*
+ * The lower 16 bits are system-specific and thus defined in
+ * system-specific headers.
+ */
+
+
+#define IO_IRQ_BASE		8	/* first IRQ assigned to I/O ASIC */
+#define IO_IRQ_LINES		32	/* number of I/O ASIC interrupts */
+
+#define IO_IRQ_NR(n)		((n) + IO_IRQ_BASE)
+#define IO_IRQ_MASK(n)		(1 << (n))
+#define IO_IRQ_ALL		0x0000ffff
+#define IO_IRQ_DMA		0xffff0000
+
+#endif /* __ASM_DEC_IOASIC_INTS_H */
diff --git a/arch/mips/include/asm/dec/kn01.h b/arch/mips/include/asm/dec/kn01.h
new file mode 100644
index 000000000..88d9ffd74
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn01.h
@@ -0,0 +1,89 @@
+/*
+ * Hardware info about DECstation DS2100/3100 systems (otherwise known as
+ * pmin/pmax or KN01).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1995,1996 by Paul M. Antoine, some code and definitions
+ * are by courtesy of Chris Fraser.
+ * Copyright (C) 2002, 2003, 2005  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN01_H
+#define __ASM_MIPS_DEC_KN01_H
+
+#define KN01_SLOT_BASE	0x10000000
+#define KN01_SLOT_SIZE	0x01000000
+
+/*
+ * Address ranges for devices.
+ */
+#define KN01_PMASK	(0*KN01_SLOT_SIZE)	/* color plane mask */
+#define KN01_PCC	(1*KN01_SLOT_SIZE)	/* PCC (DC503) cursor */
+#define KN01_VDAC	(2*KN01_SLOT_SIZE)	/* color map */
+#define KN01_RES_3	(3*KN01_SLOT_SIZE)	/* unused */
+#define KN01_RES_4	(4*KN01_SLOT_SIZE)	/* unused */
+#define KN01_RES_5	(5*KN01_SLOT_SIZE)	/* unused */
+#define KN01_RES_6	(6*KN01_SLOT_SIZE)	/* unused */
+#define KN01_ERRADDR	(7*KN01_SLOT_SIZE)	/* write error address */
+#define KN01_LANCE	(8*KN01_SLOT_SIZE)	/* LANCE (Am7990) Ethernet */
+#define KN01_LANCE_MEM	(9*KN01_SLOT_SIZE)	/* LANCE buffer memory */
+#define KN01_SII	(10*KN01_SLOT_SIZE)	/* SII (DC7061) SCSI */
+#define KN01_SII_MEM	(11*KN01_SLOT_SIZE)	/* SII buffer memory */
+#define KN01_DZ11	(12*KN01_SLOT_SIZE)	/* DZ11 (DC7085) serial */
+#define KN01_RTC	(13*KN01_SLOT_SIZE)	/* DS1287 RTC (bytes #0) */
+#define KN01_ESAR	(13*KN01_SLOT_SIZE)	/* MAC address (bytes #1) */
+#define KN01_CSR	(14*KN01_SLOT_SIZE)	/* system ctrl & status reg */
+#define KN01_SYS_ROM	(15*KN01_SLOT_SIZE)	/* system board ROM */
+
+
+/*
+ * Frame buffer memory address.
+ */
+#define KN01_VFB_MEM	0x0fc00000
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN01_CPU_INR_BUS	6	/* memory, I/O bus read/write errors */
+#define KN01_CPU_INR_VIDEO	6	/* PCC area detect #2 */
+#define KN01_CPU_INR_RTC	5	/* DS1287 RTC */
+#define KN01_CPU_INR_DZ11	4	/* DZ11 (DC7085) serial */
+#define KN01_CPU_INR_LANCE	3	/* LANCE (Am7990) Ethernet */
+#define KN01_CPU_INR_SII	2	/* SII (DC7061) SCSI */
+
+
+/*
+ * System Control & Status Register bits.
+ */
+#define KN01_CSR_MNFMOD		(1<<15)	/* MNFMOD manufacturing jumper */
+#define KN01_CSR_STATUS		(1<<14)	/* self-test result status output */
+#define KN01_CSR_PARDIS		(1<<13)	/* parity error disable */
+#define KN01_CSR_CRSRTST	(1<<12)	/* PCC test output */
+#define KN01_CSR_MONO		(1<<11)	/* mono/color fb SIMM installed */
+#define KN01_CSR_MEMERR		(1<<10)	/* write timeout error status & ack*/
+#define KN01_CSR_VINT		(1<<9)	/* PCC area detect #2 status & ack */
+#define KN01_CSR_TXDIS		(1<<8)	/* DZ11 transmit disable */
+#define KN01_CSR_VBGTRG		(1<<2)	/* blue DAC voltage over green (r/o) */
+#define KN01_CSR_VRGTRG		(1<<1)	/* red DAC voltage over green (r/o) */
+#define KN01_CSR_VRGTRB		(1<<0)	/* red DAC voltage over blue (r/o) */
+#define KN01_CSR_LEDS		(0xff<<0) /* ~diagnostic LEDs (w/o) */
+
+
+#ifndef __ASSEMBLY__
+
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+struct pt_regs;
+
+extern u16 cached_kn01_csr;
+
+extern void dec_kn01_be_init(void);
+extern int dec_kn01_be_handler(struct pt_regs *regs, int is_fixup);
+extern irqreturn_t dec_kn01_be_interrupt(int irq, void *dev_id);
+#endif
+
+#endif /* __ASM_MIPS_DEC_KN01_H */
diff --git a/arch/mips/include/asm/dec/kn02.h b/arch/mips/include/asm/dec/kn02.h
new file mode 100644
index 000000000..93430b5f4
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn02.h
@@ -0,0 +1,91 @@
+/*
+ * Hardware info about DECstation 5000/200 systems (otherwise known as
+ * 3max or KN02).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1995,1996 by Paul M. Antoine, some code and definitions
+ * are by courtesy of Chris Fraser.
+ * Copyright (C) 2002, 2003, 2005  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN02_H
+#define __ASM_MIPS_DEC_KN02_H
+
+#define KN02_SLOT_BASE	0x1fc00000
+#define KN02_SLOT_SIZE	0x00080000
+
+/*
+ * Address ranges decoded by the "system slot" logic for onboard devices.
+ */
+#define KN02_SYS_ROM	(0*KN02_SLOT_SIZE)	/* system board ROM */
+#define KN02_RES_1	(1*KN02_SLOT_SIZE)	/* unused */
+#define KN02_CHKSYN	(2*KN02_SLOT_SIZE)	/* ECC syndrome */
+#define KN02_ERRADDR	(3*KN02_SLOT_SIZE)	/* bus error address */
+#define KN02_DZ11	(4*KN02_SLOT_SIZE)	/* DZ11 (DC7085) serial */
+#define KN02_RTC	(5*KN02_SLOT_SIZE)	/* DS1287 RTC */
+#define KN02_CSR	(6*KN02_SLOT_SIZE)	/* system ctrl & status reg */
+#define KN02_SYS_ROM_7	(7*KN02_SLOT_SIZE)	/* system board ROM (alias) */
+
+
+/*
+ * System Control & Status Register bits.
+ */
+#define KN02_CSR_RES_28		(0xf<<28)	/* unused */
+#define KN02_CSR_PSU		(1<<27)		/* power supply unit warning */
+#define KN02_CSR_NVRAM		(1<<26)		/* ~NVRAM clear jumper */
+#define KN02_CSR_REFEVEN	(1<<25)		/* mem refresh bank toggle */
+#define KN02_CSR_NRMOD		(1<<24)		/* ~NRMOD manufact. jumper */
+#define KN02_CSR_IOINTEN	(0xff<<16)	/* IRQ mask bits */
+#define KN02_CSR_DIAGCHK	(1<<15)		/* diagn/norml ECC reads */
+#define KN02_CSR_DIAGGEN	(1<<14)		/* diagn/norml ECC writes */
+#define KN02_CSR_CORRECT	(1<<13)		/* ECC correct/check */
+#define KN02_CSR_LEDIAG		(1<<12)		/* ECC diagn. latch strobe */
+#define KN02_CSR_TXDIS		(1<<11)		/* DZ11 transmit disable */
+#define KN02_CSR_BNK32M		(1<<10)		/* 32M/8M stride */
+#define KN02_CSR_DIAGDN		(1<<9)		/* DIAGDN manufact. jumper */
+#define KN02_CSR_BAUD38		(1<<8)		/* DZ11 38/19kbps ext. rate */
+#define KN02_CSR_IOINT		(0xff<<0)	/* IRQ status bits (r/o) */
+#define KN02_CSR_LEDS		(0xff<<0)	/* ~diagnostic LEDs (w/o) */
+
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN02_CPU_INR_RES_6	6	/* unused */
+#define KN02_CPU_INR_BUS	5	/* memory, I/O bus read/write errors */
+#define KN02_CPU_INR_RES_4	4	/* unused */
+#define KN02_CPU_INR_RTC	3	/* DS1287 RTC */
+#define KN02_CPU_INR_CASCADE	2	/* CSR cascade */
+
+/*
+ * CSR interrupt bits.
+ */
+#define KN02_CSR_INR_DZ11	7	/* DZ11 (DC7085) serial */
+#define KN02_CSR_INR_LANCE	6	/* LANCE (Am7990) Ethernet */
+#define KN02_CSR_INR_ASC	5	/* ASC (NCR53C94) SCSI */
+#define KN02_CSR_INR_RES_4	4	/* unused */
+#define KN02_CSR_INR_RES_3	3	/* unused */
+#define KN02_CSR_INR_TC2	2	/* TURBOchannel slot #2 */
+#define KN02_CSR_INR_TC1	1	/* TURBOchannel slot #1 */
+#define KN02_CSR_INR_TC0	0	/* TURBOchannel slot #0 */
+
+
+#define KN02_IRQ_BASE		8	/* first IRQ assigned to CSR */
+#define KN02_IRQ_LINES		8	/* number of CSR interrupts */
+
+#define KN02_IRQ_NR(n)		((n) + KN02_IRQ_BASE)
+#define KN02_IRQ_MASK(n)	(1 << (n))
+#define KN02_IRQ_ALL		0xff
+
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+extern u32 cached_kn02_csr;
+extern void init_kn02_irqs(int base);
+#endif
+
+#endif /* __ASM_MIPS_DEC_KN02_H */
diff --git a/arch/mips/include/asm/dec/kn02ba.h b/arch/mips/include/asm/dec/kn02ba.h
new file mode 100644
index 000000000..81a6cc1c5
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn02ba.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/kn02ba.h
+ *
+ *	DECstation 5000/1xx (3min or KN02-BA) definitions.
+ *
+ *	Copyright (C) 2002, 2003  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN02BA_H
+#define __ASM_MIPS_DEC_KN02BA_H
+
+#include <asm/dec/kn02xa.h>		/* For common definitions. */
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN02BA_CPU_INR_HALT	6	/* HALT button */
+#define KN02BA_CPU_INR_CASCADE	5	/* I/O ASIC cascade */
+#define KN02BA_CPU_INR_TC2	4	/* TURBOchannel slot #2 */
+#define KN02BA_CPU_INR_TC1	3	/* TURBOchannel slot #1 */
+#define KN02BA_CPU_INR_TC0	2	/* TURBOchannel slot #0 */
+
+/*
+ * I/O ASIC interrupt bits.  Star marks denote non-IRQ status bits.
+ */
+#define KN02BA_IO_INR_RES_15	15	/* unused */
+#define KN02BA_IO_INR_NVRAM	14	/* (*) NVRAM clear jumper */
+#define KN02BA_IO_INR_RES_13	13	/* unused */
+#define KN02BA_IO_INR_BUS	12	/* memory, I/O bus read/write errors */
+#define KN02BA_IO_INR_RES_11	11	/* unused */
+#define KN02BA_IO_INR_NRMOD	10	/* (*) NRMOD manufacturing jumper */
+#define KN02BA_IO_INR_ASC	9	/* ASC (NCR53C94) SCSI */
+#define KN02BA_IO_INR_LANCE	8	/* LANCE (Am7990) Ethernet */
+#define KN02BA_IO_INR_SCC1	7	/* SCC (Z85C30) serial #1 */
+#define KN02BA_IO_INR_SCC0	6	/* SCC (Z85C30) serial #0 */
+#define KN02BA_IO_INR_RTC	5	/* DS1287 RTC */
+#define KN02BA_IO_INR_PSU	4	/* power supply unit warning */
+#define KN02BA_IO_INR_RES_3	3	/* unused */
+#define KN02BA_IO_INR_ASC_DATA	2	/* SCSI data ready (for PIO) */
+#define KN02BA_IO_INR_PBNC	1	/* ~HALT button debouncer */
+#define KN02BA_IO_INR_PBNO	0	/* HALT button debouncer */
+
+
+/*
+ * Memory Error Register bits.
+ */
+#define KN02BA_MER_RES_27	(1<<27)		/* unused */
+
+/*
+ * Memory Size Register bits.
+ */
+#define KN02BA_MSR_RES_17	(0x3ff<<17)	/* unused */
+
+/*
+ * I/O ASIC System Support Register bits.
+ */
+#define KN02BA_IO_SSR_TXDIS1	(1<<14)		/* SCC1 transmit disable */
+#define KN02BA_IO_SSR_TXDIS0	(1<<13)		/* SCC0 transmit disable */
+#define KN02BA_IO_SSR_RES_12	(1<<12)		/* unused */
+
+#define KN02BA_IO_SSR_LEDS	(0xff<<0)	/* ~diagnostic LEDs */
+
+#endif /* __ASM_MIPS_DEC_KN02BA_H */
diff --git a/arch/mips/include/asm/dec/kn02ca.h b/arch/mips/include/asm/dec/kn02ca.h
new file mode 100644
index 000000000..a466101eb
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn02ca.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/kn02ca.h
+ *
+ *	Personal DECstation 5000/xx (Maxine or KN02-CA) definitions.
+ *
+ *	Copyright (C) 2002, 2003  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN02CA_H
+#define __ASM_MIPS_DEC_KN02CA_H
+
+#include <asm/dec/kn02xa.h>		/* For common definitions. */
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN02CA_CPU_INR_HALT	6	/* HALT from ACCESS.Bus */
+#define KN02CA_CPU_INR_CASCADE	5	/* I/O ASIC cascade */
+#define KN02CA_CPU_INR_BUS	4	/* memory, I/O bus read/write errors */
+#define KN02CA_CPU_INR_RTC	3	/* DS1287 RTC */
+#define KN02CA_CPU_INR_TIMER	2	/* ARC periodic timer */
+
+/*
+ * I/O ASIC interrupt bits.  Star marks denote non-IRQ status bits.
+ */
+#define KN02CA_IO_INR_FLOPPY	15	/* 82077 FDC */
+#define KN02CA_IO_INR_NVRAM	14	/* (*) NVRAM clear jumper */
+#define KN02CA_IO_INR_POWERON	13	/* (*) ACCESS.Bus/power-on reset */
+#define KN02CA_IO_INR_TC0	12	/* TURBOchannel slot #0 */
+#define KN02CA_IO_INR_TIMER	12	/* ARC periodic timer (?) */
+#define KN02CA_IO_INR_ISDN	11	/* Am79C30A ISDN */
+#define KN02CA_IO_INR_NRMOD	10	/* (*) NRMOD manufacturing jumper */
+#define KN02CA_IO_INR_ASC	9	/* ASC (NCR53C94) SCSI */
+#define KN02CA_IO_INR_LANCE	8	/* LANCE (Am7990) Ethernet */
+#define KN02CA_IO_INR_HDFLOPPY	7	/* (*) HD (1.44MB) floppy status */
+#define KN02CA_IO_INR_SCC0	6	/* SCC (Z85C30) serial #0 */
+#define KN02CA_IO_INR_TC1	5	/* TURBOchannel slot #1 */
+#define KN02CA_IO_INR_XDFLOPPY	4	/* (*) XD (2.88MB) floppy status */
+#define KN02CA_IO_INR_VIDEO	3	/* framebuffer */
+#define KN02CA_IO_INR_XVIDEO	2	/* ~framebuffer */
+#define KN02CA_IO_INR_AB_XMIT	1	/* ACCESS.bus transmit */
+#define KN02CA_IO_INR_AB_RECV	0	/* ACCESS.bus receive */
+
+
+/*
+ * Memory Error Register bits.
+ */
+#define KN02CA_MER_INTR		(1<<27)		/* ARC IRQ status & ack */
+
+/*
+ * Memory Size Register bits.
+ */
+#define KN02CA_MSR_INTREN	(1<<26)		/* ARC periodic IRQ enable */
+#define KN02CA_MSR_MS10EN	(1<<25)		/* 10/1ms IRQ period select */
+#define KN02CA_MSR_PFORCE	(0xf<<21)	/* byte lane error force */
+#define KN02CA_MSR_MABEN	(1<<20)		/* A side VFB address enable */
+#define KN02CA_MSR_LASTBANK	(0x7<<17)	/* onboard RAM bank # */
+
+/*
+ * I/O ASIC System Support Register bits.
+ */
+#define KN03CA_IO_SSR_RES_14	(1<<14)		/* unused */
+#define KN03CA_IO_SSR_RES_13	(1<<13)		/* unused */
+#define KN03CA_IO_SSR_ISDN_RST	(1<<12)		/* ~ISDN (Am79C30A) reset */
+
+#define KN03CA_IO_SSR_FLOPPY_RST (1<<7)		/* ~FDC (82077) reset */
+#define KN03CA_IO_SSR_VIDEO_RST	(1<<6)		/* ~framebuffer reset */
+#define KN03CA_IO_SSR_AB_RST	(1<<5)		/* ACCESS.bus reset */
+#define KN03CA_IO_SSR_RES_4	(1<<4)		/* unused */
+#define KN03CA_IO_SSR_RES_3	(1<<4)		/* unused */
+#define KN03CA_IO_SSR_RES_2	(1<<2)		/* unused */
+#define KN03CA_IO_SSR_RES_1	(1<<1)		/* unused */
+#define KN03CA_IO_SSR_LED	(1<<0)		/* power LED */
+
+#endif /* __ASM_MIPS_DEC_KN02CA_H */
diff --git a/arch/mips/include/asm/dec/kn02xa.h b/arch/mips/include/asm/dec/kn02xa.h
new file mode 100644
index 000000000..b56b4577f
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn02xa.h
@@ -0,0 +1,84 @@
+/*
+ * Hardware info common to DECstation 5000/1xx systems (otherwise
+ * known as 3min or kn02ba) and Personal DECstations 5000/xx ones
+ * (otherwise known as maxine or kn02ca).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1995,1996 by Paul M. Antoine, some code and definitions
+ * are by courtesy of Chris Fraser.
+ * Copyright (C) 2000, 2002, 2003, 2005  Maciej W. Rozycki
+ *
+ * These are addresses which have to be known early in the boot process.
+ * For other addresses refer to tc.h, ioasic_addrs.h and friends.
+ */
+#ifndef __ASM_MIPS_DEC_KN02XA_H
+#define __ASM_MIPS_DEC_KN02XA_H
+
+#include <asm/dec/ioasic_addrs.h>
+
+#define KN02XA_SLOT_BASE	0x1c000000
+
+/*
+ * Memory control ASIC registers.
+ */
+#define KN02XA_MER		0x0c400000	/* memory error register */
+#define KN02XA_MSR		0x0c800000	/* memory size register */
+
+/*
+ * CPU control ASIC registers.
+ */
+#define KN02XA_MEM_CONF		0x0e000000	/* write timeout config */
+#define KN02XA_EAR		0x0e000004	/* error address register */
+#define KN02XA_BOOT0		0x0e000008	/* boot 0 register */
+#define KN02XA_MEM_INTR		0x0e00000c	/* write err IRQ stat & ack */
+
+/*
+ * Memory Error Register bits, common definitions.
+ * The rest is defined in system-specific headers.
+ */
+#define KN02XA_MER_RES_28	(0xf<<28)	/* unused */
+#define KN02XA_MER_RES_17	(0x3ff<<17)	/* unused */
+#define KN02XA_MER_PAGERR	(1<<16)		/* 2k page boundary error */
+#define KN02XA_MER_TRANSERR	(1<<15)		/* transfer length error */
+#define KN02XA_MER_PARDIS	(1<<14)		/* parity error disable */
+#define KN02XA_MER_SIZE		(1<<13)		/* r/o mirror of MSR_SIZE */
+#define KN02XA_MER_RES_12	(1<<12)		/* unused */
+#define KN02XA_MER_BYTERR	(0xf<<8)	/* byte lane error bitmask: */
+#define KN02XA_MER_BYTERR_3	(0x8<<8)	/* byte lane #3 */
+#define KN02XA_MER_BYTERR_2	(0x4<<8)	/* byte lane #2 */
+#define KN02XA_MER_BYTERR_1	(0x2<<8)	/* byte lane #1 */
+#define KN02XA_MER_BYTERR_0	(0x1<<8)	/* byte lane #0 */
+#define KN02XA_MER_RES_0	(0xff<<0)	/* unused */
+
+/*
+ * Memory Size Register bits, common definitions.
+ * The rest is defined in system-specific headers.
+ */
+#define KN02XA_MSR_RES_27	(0x1f<<27)	/* unused */
+#define KN02XA_MSR_RES_14	(0x7<<14)	/* unused */
+#define KN02XA_MSR_SIZE		(1<<13)		/* 16M/4M stride */
+#define KN02XA_MSR_RES_0	(0x1fff<<0)	/* unused */
+
+/*
+ * Error Address Register bits.
+ */
+#define KN02XA_EAR_RES_29	(0x7<<29)	/* unused */
+#define KN02XA_EAR_ADDRESS	(0x7ffffff<<2)	/* address involved */
+#define KN02XA_EAR_RES_0	(0x3<<0)	/* unused */
+
+
+#ifndef __ASSEMBLY__
+
+#include <linux/interrupt.h>
+
+struct pt_regs;
+
+extern void dec_kn02xa_be_init(void);
+extern int dec_kn02xa_be_handler(struct pt_regs *regs, int is_fixup);
+extern irqreturn_t dec_kn02xa_be_interrupt(int irq, void *dev_id);
+#endif
+
+#endif /* __ASM_MIPS_DEC_KN02XA_H */
diff --git a/arch/mips/include/asm/dec/kn03.h b/arch/mips/include/asm/dec/kn03.h
new file mode 100644
index 000000000..edede923f
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn03.h
@@ -0,0 +1,74 @@
+/*
+ * Hardware info about DECstation 5000/2x0 systems (otherwise known as
+ * 3max+) and DECsystem 5900 systems (otherwise known as bigmax) which
+ * differ mechanically but are otherwise identical (both are known as
+ * KN03).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1995,1996 by Paul M. Antoine, some code and definitions
+ * are by courtesy of Chris Fraser.
+ * Copyright (C) 2000, 2002, 2003, 2005  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN03_H
+#define __ASM_MIPS_DEC_KN03_H
+
+#include <asm/dec/ecc.h>
+#include <asm/dec/ioasic_addrs.h>
+
+#define KN03_SLOT_BASE		0x1f800000
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN03_CPU_INR_HALT	6	/* HALT button */
+#define KN03_CPU_INR_BUS	5	/* memory, I/O bus read/write errors */
+#define KN03_CPU_INR_RES_4	4	/* unused */
+#define KN03_CPU_INR_RTC	3	/* DS1287 RTC */
+#define KN03_CPU_INR_CASCADE	2	/* I/O ASIC cascade */
+
+/*
+ * I/O ASIC interrupt bits.  Star marks denote non-IRQ status bits.
+ */
+#define KN03_IO_INR_3MAXP	15	/* (*) 3max+/bigmax ID */
+#define KN03_IO_INR_NVRAM	14	/* (*) NVRAM clear jumper */
+#define KN03_IO_INR_TC2		13	/* TURBOchannel slot #2 */
+#define KN03_IO_INR_TC1		12	/* TURBOchannel slot #1 */
+#define KN03_IO_INR_TC0		11	/* TURBOchannel slot #0 */
+#define KN03_IO_INR_NRMOD	10	/* (*) NRMOD manufacturing jumper */
+#define KN03_IO_INR_ASC		9	/* ASC (NCR53C94) SCSI */
+#define KN03_IO_INR_LANCE	8	/* LANCE (Am7990) Ethernet */
+#define KN03_IO_INR_SCC1	7	/* SCC (Z85C30) serial #1 */
+#define KN03_IO_INR_SCC0	6	/* SCC (Z85C30) serial #0 */
+#define KN03_IO_INR_RTC		5	/* DS1287 RTC */
+#define KN03_IO_INR_PSU		4	/* power supply unit warning */
+#define KN03_IO_INR_RES_3	3	/* unused */
+#define KN03_IO_INR_ASC_DATA	2	/* SCSI data ready (for PIO) */
+#define KN03_IO_INR_PBNC	1	/* ~HALT button debouncer */
+#define KN03_IO_INR_PBNO	0	/* HALT button debouncer */
+
+
+/*
+ * Memory Control Register bits.
+ */
+#define KN03_MCR_RES_16		(0xffff<<16)	/* unused */
+#define KN03_MCR_DIAGCHK	(1<<15)		/* diagn/norml ECC reads */
+#define KN03_MCR_DIAGGEN	(1<<14)		/* diagn/norml ECC writes */
+#define KN03_MCR_CORRECT	(1<<13)		/* ECC correct/check */
+#define KN03_MCR_RES_11		(0x3<<12)	/* unused */
+#define KN03_MCR_BNK32M		(1<<10)		/* 32M/8M stride */
+#define KN03_MCR_RES_7		(0x7<<7)	/* unused */
+#define KN03_MCR_CHECK		(0x7f<<0)	/* diagnostic check bits */
+
+/*
+ * I/O ASIC System Support Register bits.
+ */
+#define KN03_IO_SSR_TXDIS1	(1<<14)		/* SCC1 transmit disable */
+#define KN03_IO_SSR_TXDIS0	(1<<13)		/* SCC0 transmit disable */
+#define KN03_IO_SSR_RES_12	(1<<12)		/* unused */
+
+#define KN03_IO_SSR_LEDS	(0xff<<0)	/* ~diagnostic LEDs */
+
+#endif /* __ASM_MIPS_DEC_KN03_H */
diff --git a/arch/mips/include/asm/dec/kn05.h b/arch/mips/include/asm/dec/kn05.h
new file mode 100644
index 000000000..3b1524e9f
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn05.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/kn05.h
+ *
+ *	DECstation/DECsystem 5000/260 (4max+ or KN05), 5000/150 (4min
+ *	or KN04-BA), Personal DECstation/DECsystem 5000/50 (4maxine or
+ *	KN04-CA) and DECsystem 5900/260 (KN05) R4k CPU card MB ASIC
+ *	definitions.
+ *
+ *	Copyright (C) 2002, 2003, 2005, 2008  Maciej W. Rozycki
+ *
+ *	WARNING!  All this information is pure guesswork based on the
+ *	ROM.  It is provided here in hope it will give someone some
+ *	food for thought.  No documentation for the KN05 nor the KN04
+ *	module has been located so far.
+ */
+#ifndef __ASM_MIPS_DEC_KN05_H
+#define __ASM_MIPS_DEC_KN05_H
+
+#include <asm/dec/ioasic_addrs.h>
+
+/*
+ * The oncard MB (Memory Buffer) ASIC provides an additional address
+ * decoder.  Certain address ranges within the "high" 16 slots are
+ * passed to the I/O ASIC's decoder like with the KN03 or KN02-BA/CA.
+ * Others are handled locally.  "Low" slots are always passed.
+ */
+#define KN4K_SLOT_BASE	0x1fc00000
+
+#define KN4K_MB_ROM	(0*IOASIC_SLOT_SIZE)	/* KN05/KN04 card ROM */
+#define KN4K_IOCTL	(1*IOASIC_SLOT_SIZE)	/* I/O ASIC */
+#define KN4K_ESAR	(2*IOASIC_SLOT_SIZE)	/* LANCE MAC address chip */
+#define KN4K_LANCE	(3*IOASIC_SLOT_SIZE)	/* LANCE Ethernet */
+#define KN4K_MB_INT	(4*IOASIC_SLOT_SIZE)	/* MB interrupt register */
+#define KN4K_MB_EA	(5*IOASIC_SLOT_SIZE)	/* MB error address? */
+#define KN4K_MB_EC	(6*IOASIC_SLOT_SIZE)	/* MB error ??? */
+#define KN4K_MB_CSR	(7*IOASIC_SLOT_SIZE)	/* MB control & status */
+#define KN4K_RES_08	(8*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_RES_09	(9*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_RES_10	(10*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_RES_11	(11*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_SCSI	(12*IOASIC_SLOT_SIZE)	/* ASC SCSI */
+#define KN4K_RES_13	(13*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_RES_14	(14*IOASIC_SLOT_SIZE)	/* unused? */
+#define KN4K_RES_15	(15*IOASIC_SLOT_SIZE)	/* unused? */
+
+/*
+ * MB ASIC interrupt bits.
+ */
+#define KN4K_MB_INR_MB		4	/* ??? */
+#define KN4K_MB_INR_MT		3	/* memory, I/O bus read/write errors */
+#define KN4K_MB_INR_RES_2	2	/* unused */
+#define KN4K_MB_INR_RTC		1	/* RTC */
+#define KN4K_MB_INR_TC		0	/* I/O ASIC cascade */
+
+/*
+ * Bits for the MB interrupt register.
+ * The register appears read-only.
+ */
+#define KN4K_MB_INT_IRQ		(0x1f<<0)	/* CPU Int[4:0] status. */
+#define KN4K_MB_INT_IRQ_N(n)	(1<<(n))	/* Individual status bits. */
+
+/*
+ * Bits for the MB control & status register.
+ * Set to 0x00bf8001 for KN05 and to 0x003f8000 for KN04 by the firmware.
+ */
+#define KN4K_MB_CSR_PF		(1<<0)		/* PreFetching enable? */
+#define KN4K_MB_CSR_F		(1<<1)		/* ??? */
+#define KN4K_MB_CSR_ECC		(0xff<<2)	/* ??? */
+#define KN4K_MB_CSR_OD		(1<<10)		/* ??? */
+#define KN4K_MB_CSR_CP		(1<<11)		/* ??? */
+#define KN4K_MB_CSR_UNC		(1<<12)		/* ??? */
+#define KN4K_MB_CSR_IM		(1<<13)		/* ??? */
+#define KN4K_MB_CSR_NC		(1<<14)		/* ??? */
+#define KN4K_MB_CSR_EE		(1<<15)		/* (bus) Exception Enable? */
+#define KN4K_MB_CSR_MSK		(0x1f<<16)	/* CPU Int[4:0] mask */
+#define KN4K_MB_CSR_MSK_N(n)	(1<<((n)+16))	/* Individual mask bits. */
+#define KN4K_MB_CSR_FW		(1<<21)		/* ??? */
+#define KN4K_MB_CSR_W		(1<<31)		/* ??? */
+
+#endif /* __ASM_MIPS_DEC_KN05_H */
diff --git a/arch/mips/include/asm/dec/kn230.h b/arch/mips/include/asm/dec/kn230.h
new file mode 100644
index 000000000..cb13a7799
--- /dev/null
+++ b/arch/mips/include/asm/dec/kn230.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/kn230.h
+ *
+ *	DECsystem 5100 (MIPSmate or KN230) definitions.
+ *
+ *	Copyright (C) 2002, 2003  Maciej W. Rozycki
+ */
+#ifndef __ASM_MIPS_DEC_KN230_H
+#define __ASM_MIPS_DEC_KN230_H
+
+/*
+ * CPU interrupt bits.
+ */
+#define KN230_CPU_INR_HALT	6	/* HALT button */
+#define KN230_CPU_INR_BUS	5	/* memory, I/O bus read/write errors */
+#define KN230_CPU_INR_RTC	4	/* DS1287 RTC */
+#define KN230_CPU_INR_SII	3	/* SII (DC7061) SCSI */
+#define KN230_CPU_INR_LANCE	3	/* LANCE (Am7990) Ethernet */
+#define KN230_CPU_INR_DZ11	2	/* DZ11 (DC7085) serial */
+
+#endif /* __ASM_MIPS_DEC_KN230_H */
diff --git a/arch/mips/include/asm/dec/machtype.h b/arch/mips/include/asm/dec/machtype.h
new file mode 100644
index 000000000..a6ecdebc4
--- /dev/null
+++ b/arch/mips/include/asm/dec/machtype.h
@@ -0,0 +1,27 @@
+/*
+ * Various machine type macros
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1998, 2000 Harald Koerfgen
+ */
+
+#ifndef __ASM_DEC_MACHTYPE_H
+#define __ASM_DEC_MACHTYPE_H
+
+#include <asm/bootinfo.h>
+
+#define TURBOCHANNEL	(mips_machtype == MACH_DS5000_200 || \
+			 mips_machtype == MACH_DS5000_1XX || \
+			 mips_machtype == MACH_DS5000_XX  || \
+			 mips_machtype == MACH_DS5000_2X0 || \
+			 mips_machtype == MACH_DS5900)
+
+#define IOASIC		(mips_machtype == MACH_DS5000_1XX || \
+			 mips_machtype == MACH_DS5000_XX  || \
+			 mips_machtype == MACH_DS5000_2X0 || \
+			 mips_machtype == MACH_DS5900)
+
+#endif
diff --git a/arch/mips/include/asm/dec/prom.h b/arch/mips/include/asm/dec/prom.h
new file mode 100644
index 000000000..908e96e3a
--- /dev/null
+++ b/arch/mips/include/asm/dec/prom.h
@@ -0,0 +1,165 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/prom.h
+ *
+ *	DECstation PROM interface.
+ *
+ *	Copyright (C) 2002  Maciej W. Rozycki
+ *
+ *	Based on arch/mips/dec/prom/prom.h by the Anonymous.
+ */
+#ifndef _ASM_DEC_PROM_H
+#define _ASM_DEC_PROM_H
+
+#include <linux/types.h>
+
+#include <asm/addrspace.h>
+
+/*
+ * PMAX/3MAX PROM entry points for DS2100/3100's and DS5000/2xx's.
+ * Many of these will work for MIPSen as well!
+ */
+#define VEC_RESET		(u64 *)CKSEG1ADDR(0x1fc00000)
+							/* Prom base address */
+
+#define PMAX_PROM_ENTRY(x)	(VEC_RESET + (x))	/* Prom jump table */
+
+#define PMAX_PROM_HALT		PMAX_PROM_ENTRY(2)	/* valid on MIPSen */
+#define PMAX_PROM_AUTOBOOT	PMAX_PROM_ENTRY(5)	/* valid on MIPSen */
+#define PMAX_PROM_OPEN		PMAX_PROM_ENTRY(6)
+#define PMAX_PROM_READ		PMAX_PROM_ENTRY(7)
+#define PMAX_PROM_CLOSE		PMAX_PROM_ENTRY(10)
+#define PMAX_PROM_LSEEK		PMAX_PROM_ENTRY(11)
+#define PMAX_PROM_GETCHAR	PMAX_PROM_ENTRY(12)
+#define PMAX_PROM_PUTCHAR	PMAX_PROM_ENTRY(13)	/* 12 on MIPSen */
+#define PMAX_PROM_GETS		PMAX_PROM_ENTRY(15)
+#define PMAX_PROM_PRINTF	PMAX_PROM_ENTRY(17)
+#define PMAX_PROM_GETENV	PMAX_PROM_ENTRY(33)	/* valid on MIPSen */
+
+
+/*
+ * Magic number indicating REX PROM available on DECstation.  Found in
+ * register a2 on transfer of control to program from PROM.
+ */
+#define REX_PROM_MAGIC		0x30464354
+
+/* KN04 and KN05 are REX PROMs, so only do the check for R3k systems.  */
+static inline bool prom_is_rex(u32 magic)
+{
+	return !IS_ENABLED(CONFIG_CPU_R3000) || magic == REX_PROM_MAGIC;
+}
+
+/*
+ * 3MIN/MAXINE PROM entry points for DS5000/1xx's, DS5000/xx's and
+ * DS5000/2x0.
+ */
+#define REX_PROM_GETBITMAP	0x84/4	/* get mem bitmap */
+#define REX_PROM_GETCHAR	0x24/4	/* getch() */
+#define REX_PROM_GETENV		0x64/4	/* get env. variable */
+#define REX_PROM_GETSYSID	0x80/4	/* get system id */
+#define REX_PROM_GETTCINFO	0xa4/4
+#define REX_PROM_PRINTF		0x30/4	/* printf() */
+#define REX_PROM_SLOTADDR	0x6c/4	/* slotaddr */
+#define REX_PROM_BOOTINIT	0x54/4	/* open() */
+#define REX_PROM_BOOTREAD	0x58/4	/* read() */
+#define REX_PROM_CLEARCACHE	0x7c/4
+
+
+/*
+ * Used by rex_getbitmap().
+ */
+typedef struct {
+	int pagesize;
+	unsigned char bitmap[];
+} memmap;
+
+
+/*
+ * Function pointers as read from a PROM's callback vector.
+ */
+extern int (*__rex_bootinit)(void);
+extern int (*__rex_bootread)(void);
+extern int (*__rex_getbitmap)(memmap *);
+extern unsigned long *(*__rex_slot_address)(int);
+extern void *(*__rex_gettcinfo)(void);
+extern int (*__rex_getsysid)(void);
+extern void (*__rex_clear_cache)(void);
+
+extern int (*__prom_getchar)(void);
+extern char *(*__prom_getenv)(char *);
+extern int (*__prom_printf)(char *, ...);
+
+extern int (*__pmax_open)(char*, int);
+extern int (*__pmax_lseek)(int, long, int);
+extern int (*__pmax_read)(int, void *, int);
+extern int (*__pmax_close)(int);
+
+
+#ifdef CONFIG_64BIT
+
+/*
+ * On MIPS64 we have to call PROM functions via a helper
+ * dispatcher to accommodate ABI incompatibilities.
+ */
+#define __DEC_PROM_O32(fun, arg) fun arg __asm__(#fun); \
+				 __asm__(#fun " = call_o32")
+
+int __DEC_PROM_O32(_rex_bootinit, (int (*)(void), void *));
+int __DEC_PROM_O32(_rex_bootread, (int (*)(void), void *));
+int __DEC_PROM_O32(_rex_getbitmap, (int (*)(memmap *), void *, memmap *));
+unsigned long *__DEC_PROM_O32(_rex_slot_address,
+			     (unsigned long *(*)(int), void *, int));
+void *__DEC_PROM_O32(_rex_gettcinfo, (void *(*)(void), void *));
+int __DEC_PROM_O32(_rex_getsysid, (int (*)(void), void *));
+void __DEC_PROM_O32(_rex_clear_cache, (void (*)(void), void *));
+
+int __DEC_PROM_O32(_prom_getchar, (int (*)(void), void *));
+char *__DEC_PROM_O32(_prom_getenv, (char *(*)(char *), void *, char *));
+int __DEC_PROM_O32(_prom_printf, (int (*)(char *, ...), void *, char *, ...));
+
+
+#define rex_bootinit()		_rex_bootinit(__rex_bootinit, NULL)
+#define rex_bootread()		_rex_bootread(__rex_bootread, NULL)
+#define rex_getbitmap(x)	_rex_getbitmap(__rex_getbitmap, NULL, x)
+#define rex_slot_address(x)	_rex_slot_address(__rex_slot_address, NULL, x)
+#define rex_gettcinfo()		_rex_gettcinfo(__rex_gettcinfo, NULL)
+#define rex_getsysid()		_rex_getsysid(__rex_getsysid, NULL)
+#define rex_clear_cache()	_rex_clear_cache(__rex_clear_cache, NULL)
+
+#define prom_getchar()		_prom_getchar(__prom_getchar, NULL)
+#define prom_getenv(x)		_prom_getenv(__prom_getenv, NULL, x)
+#define prom_printf(x...)	_prom_printf(__prom_printf, NULL, x)
+
+#else /* !CONFIG_64BIT */
+
+/*
+ * On plain MIPS we just call PROM functions directly.
+ */
+#define rex_bootinit		__rex_bootinit
+#define rex_bootread		__rex_bootread
+#define rex_getbitmap		__rex_getbitmap
+#define rex_slot_address	__rex_slot_address
+#define rex_gettcinfo		__rex_gettcinfo
+#define rex_getsysid		__rex_getsysid
+#define rex_clear_cache		__rex_clear_cache
+
+#define prom_getchar		__prom_getchar
+#define prom_getenv		__prom_getenv
+#define prom_printf		__prom_printf
+
+#define pmax_open		__pmax_open
+#define pmax_lseek		__pmax_lseek
+#define pmax_read		__pmax_read
+#define pmax_close		__pmax_close
+
+#endif /* !CONFIG_64BIT */
+
+
+extern void prom_meminit(u32);
+extern void prom_identify_arch(u32);
+extern void prom_init_cmdline(s32, s32 *, u32);
+
+extern void register_prom_console(void);
+extern void unregister_prom_console(void);
+
+#endif /* _ASM_DEC_PROM_H */
diff --git a/arch/mips/include/asm/dec/system.h b/arch/mips/include/asm/dec/system.h
new file mode 100644
index 000000000..d0873fd4e
--- /dev/null
+++ b/arch/mips/include/asm/dec/system.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *	include/asm-mips/dec/system.h
+ *
+ *	Generic DECstation/DECsystem bits.
+ *
+ *	Copyright (C) 2005, 2006  Maciej W. Rozycki
+ */
+#ifndef __ASM_DEC_SYSTEM_H
+#define __ASM_DEC_SYSTEM_H
+
+extern unsigned long dec_kn_slot_base, dec_kn_slot_size;
+extern int dec_tc_bus;
+
+#endif /* __ASM_DEC_SYSTEM_H */