MIPS: generic: Convert SEAD-3 to a generic board

Convert the MIPS SEAD-3 board support to be a generic board, supported
by generic kernels.

Because the SEAD-3 boot protocol was defined long ago and we don't want
to force a switch to the UHI protocol, SEAD-3 is added as a legacy board
which is detected by reading the REVISION register. This may technically
not be a valid memory read & future work will include attempting to
handle that gracefully. In practice since SEAD-3 is the only legacy
board supported by the generic kernel so far the read will only happen
on SEAD-3 boards, and even once Malta is converted the same REVISION
register exists there too. Other boards such as Boston, Ci20 & Ci40 will
use the UHI boot protocol & thus not run any of the legacy board detect
functions.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14354/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

7 files changed, 0 insertions, 567 deletions

diff --git a/arch/mips/mti-sead3/Makefile b/arch/mips/mti-sead3/Makefile
deleted file mode 100644
index 1674b9c..0000000
--- a/arch/mips/mti-sead3/Makefile
+++ /dev/null
@@ -1,15 +0,0 @@
-#
-# Carsten Langgaard, carstenl@mips.com
-# Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
-#
-# Copyright (C) 2008 Wind River Systems, Inc.
-#   written by Ralf Baechle <ralf@linux-mips.org>
-#
-# Copyright (C) 2012 MIPS Technoligies, Inc.  All rights reserved.
-# Steven J. Hill <sjhill@mips.com>
-#
-obj-y := sead3-dtshim.o
-obj-y += sead3-init.o
-obj-y += sead3-int.o
-obj-y += sead3-setup.o
-obj-y += sead3-time.o
diff --git a/arch/mips/mti-sead3/Platform b/arch/mips/mti-sead3/Platform
deleted file mode 100644
index 3870924..0000000
--- a/arch/mips/mti-sead3/Platform
+++ /dev/null
@@ -1,7 +0,0 @@
-#
-# MIPS SEAD-3 board
-#
-platform-$(CONFIG_MIPS_SEAD3)	+= mti-sead3/
-cflags-$(CONFIG_MIPS_SEAD3)	+= -I$(srctree)/arch/mips/include/asm/mach-sead3
-load-$(CONFIG_MIPS_SEAD3)	+= 0xffffffff80100000
-all-$(CONFIG_MIPS_SEAD3)	:= $(COMPRESSION_FNAME).srec
diff --git a/arch/mips/mti-sead3/sead3-dtshim.c b/arch/mips/mti-sead3/sead3-dtshim.c
deleted file mode 100644
index d6b0708..0000000
--- a/arch/mips/mti-sead3/sead3-dtshim.c
+++ /dev/null
@@ -1,292 +0,0 @@
-/*
- * Copyright (C) 2016 Imagination Technologies
- * Author: Paul Burton <paul.burton@imgtec.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- */
-
-#define pr_fmt(fmt) "sead3-dtshim: " fmt
-
-#include <linux/errno.h>
-#include <linux/libfdt.h>
-#include <linux/printk.h>
-
-#include <asm/fw/fw.h>
-#include <asm/io.h>
-
-#define SEAD_CONFIG			CKSEG1ADDR(0x1b100110)
-#define SEAD_CONFIG_GIC_PRESENT		BIT(1)
-
-static unsigned char fdt_buf[16 << 10] __initdata;
-
-static int append_memory(void *fdt)
-{
-	unsigned long phys_memsize, memsize;
-	__be32 mem_array[2];
-	int err, mem_off;
-	char *var;
-
-	/* find memory size from the bootloader environment */
-	var = fw_getenv("memsize");
-	if (var) {
-		err = kstrtoul(var, 0, &phys_memsize);
-		if (err) {
-			pr_err("Failed to read memsize env variable '%s'\n",
-			       var);
-			return -EINVAL;
-		}
-	} else {
-		pr_warn("The bootloader didn't provide memsize: defaulting to 32MB\n");
-		phys_memsize = 32 << 20;
-	}
-
-	/* default to using all available RAM */
-	memsize = phys_memsize;
-
-	/* allow the user to override the usable memory */
-	var = strstr(arcs_cmdline, "memsize=");
-	if (var)
-		memsize = memparse(var + strlen("memsize="), NULL);
-
-	/* if the user says there's more RAM than we thought, believe them */
-	phys_memsize = max_t(unsigned long, phys_memsize, memsize);
-
-	/* find or add a memory node */
-	mem_off = fdt_path_offset(fdt, "/memory");
-	if (mem_off == -FDT_ERR_NOTFOUND)
-		mem_off = fdt_add_subnode(fdt, 0, "memory");
-	if (mem_off < 0) {
-		pr_err("Unable to find or add memory DT node: %d\n", mem_off);
-		return mem_off;
-	}
-
-	err = fdt_setprop_string(fdt, mem_off, "device_type", "memory");
-	if (err) {
-		pr_err("Unable to set memory node device_type: %d\n", err);
-		return err;
-	}
-
-	mem_array[0] = 0;
-	mem_array[1] = cpu_to_be32(phys_memsize);
-	err = fdt_setprop(fdt, mem_off, "reg", mem_array, sizeof(mem_array));
-	if (err) {
-		pr_err("Unable to set memory regs property: %d\n", err);
-		return err;
-	}
-
-	mem_array[0] = 0;
-	mem_array[1] = cpu_to_be32(memsize);
-	err = fdt_setprop(fdt, mem_off, "linux,usable-memory",
-			  mem_array, sizeof(mem_array));
-	if (err) {
-		pr_err("Unable to set linux,usable-memory property: %d\n", err);
-		return err;
-	}
-
-	return 0;
-}
-
-static int remove_gic(void *fdt)
-{
-	const unsigned int cpu_ehci_int = 2;
-	const unsigned int cpu_uart_int = 4;
-	const unsigned int cpu_eth_int = 6;
-	int gic_off, cpu_off, uart_off, eth_off, ehci_off, err;
-	uint32_t cfg, cpu_phandle;
-
-	/* leave the GIC node intact if a GIC is present */
-	cfg = __raw_readl((uint32_t *)SEAD_CONFIG);
-	if (cfg & SEAD_CONFIG_GIC_PRESENT)
-		return 0;
-
-	gic_off = fdt_node_offset_by_compatible(fdt, -1, "mti,gic");
-	if (gic_off < 0) {
-		pr_err("unable to find DT GIC node: %d\n", gic_off);
-		return gic_off;
-	}
-
-	err = fdt_nop_node(fdt, gic_off);
-	if (err) {
-		pr_err("unable to nop GIC node\n");
-		return err;
-	}
-
-	cpu_off = fdt_node_offset_by_compatible(fdt, -1,
-			"mti,cpu-interrupt-controller");
-	if (cpu_off < 0) {
-		pr_err("unable to find CPU intc node: %d\n", cpu_off);
-		return cpu_off;
-	}
-
-	cpu_phandle = fdt_get_phandle(fdt, cpu_off);
-	if (!cpu_phandle) {
-		pr_err("unable to get CPU intc phandle\n");
-		return -EINVAL;
-	}
-
-	err = fdt_setprop_u32(fdt, 0, "interrupt-parent", cpu_phandle);
-	if (err) {
-		pr_err("unable to set root interrupt-parent: %d\n", err);
-		return err;
-	}
-
-	uart_off = fdt_node_offset_by_compatible(fdt, -1, "ns16550a");
-	while (uart_off >= 0) {
-		err = fdt_setprop_u32(fdt, uart_off, "interrupts",
-				      cpu_uart_int);
-		if (err) {
-			pr_err("unable to set UART interrupts property: %d\n",
-			       err);
-			return err;
-		}
-
-		uart_off = fdt_node_offset_by_compatible(fdt, uart_off,
-							 "ns16550a");
-	}
-	if (uart_off != -FDT_ERR_NOTFOUND) {
-		pr_err("error searching for UART DT node: %d\n", uart_off);
-		return uart_off;
-	}
-
-	eth_off = fdt_node_offset_by_compatible(fdt, -1, "smsc,lan9115");
-	if (eth_off < 0) {
-		pr_err("unable to find ethernet DT node: %d\n", eth_off);
-		return eth_off;
-	}
-
-	err = fdt_setprop_u32(fdt, eth_off, "interrupts", cpu_eth_int);
-	if (err) {
-		pr_err("unable to set ethernet interrupts property: %d\n", err);
-		return err;
-	}
-
-	ehci_off = fdt_node_offset_by_compatible(fdt, -1, "mti,sead3-ehci");
-	if (ehci_off < 0) {
-		pr_err("unable to find EHCI DT node: %d\n", ehci_off);
-		return ehci_off;
-	}
-
-	err = fdt_setprop_u32(fdt, ehci_off, "interrupts", cpu_ehci_int);
-	if (err) {
-		pr_err("unable to set EHCI interrupts property: %d\n", err);
-		return err;
-	}
-
-	return 0;
-}
-
-static int serial_config(void *fdt)
-{
-	const char *yamontty, *mode_var;
-	char mode_var_name[9], path[18], parity;
-	unsigned int uart, baud, stop_bits;
-	bool hw_flow;
-	int chosen_off, err;
-
-	yamontty = fw_getenv("yamontty");
-	if (!yamontty || !strcmp(yamontty, "tty0")) {
-		uart = 0;
-	} else if (!strcmp(yamontty, "tty1")) {
-		uart = 1;
-	} else {
-		pr_warn("yamontty environment variable '%s' invalid\n",
-			yamontty);
-		uart = 0;
-	}
-
-	baud = stop_bits = 0;
-	parity = 0;
-	hw_flow = false;
-
-	snprintf(mode_var_name, sizeof(mode_var_name), "modetty%u", uart);
-	mode_var = fw_getenv(mode_var_name);
-	if (mode_var) {
-		while (mode_var[0] >= '0' && mode_var[0] <= '9') {
-			baud *= 10;
-			baud += mode_var[0] - '0';
-			mode_var++;
-		}
-		if (mode_var[0] == ',')
-			mode_var++;
-		if (mode_var[0])
-			parity = mode_var[0];
-		if (mode_var[0] == ',')
-			mode_var++;
-		if (mode_var[0])
-			stop_bits = mode_var[0] - '0';
-		if (mode_var[0] == ',')
-			mode_var++;
-		if (!strcmp(mode_var, "hw"))
-			hw_flow = true;
-	}
-
-	if (!baud)
-		baud = 38400;
-
-	if (parity != 'e' && parity != 'n' && parity != 'o')
-		parity = 'n';
-
-	if (stop_bits != 7 && stop_bits != 8)
-		stop_bits = 8;
-
-	WARN_ON(snprintf(path, sizeof(path), "uart%u:%u%c%u%s",
-			 uart, baud, parity, stop_bits,
-			 hw_flow ? "r" : "") >= sizeof(path));
-
-	/* find or add chosen node */
-	chosen_off = fdt_path_offset(fdt, "/chosen");
-	if (chosen_off == -FDT_ERR_NOTFOUND)
-		chosen_off = fdt_path_offset(fdt, "/chosen@0");
-	if (chosen_off == -FDT_ERR_NOTFOUND)
-		chosen_off = fdt_add_subnode(fdt, 0, "chosen");
-	if (chosen_off < 0) {
-		pr_err("Unable to find or add DT chosen node: %d\n",
-		       chosen_off);
-		return chosen_off;
-	}
-
-	err = fdt_setprop_string(fdt, chosen_off, "stdout-path", path);
-	if (err) {
-		pr_err("Unable to set stdout-path property: %d\n", err);
-		return err;
-	}
-
-	return 0;
-}
-
-void __init *sead3_dt_shim(void *fdt)
-{
-	int err;
-
-	if (fdt_check_header(fdt))
-		panic("Corrupt DT");
-
-	/* if this isn't SEAD3, leave the DT alone */
-	if (fdt_node_check_compatible(fdt, 0, "mti,sead-3"))
-		return fdt;
-
-	err = fdt_open_into(fdt, fdt_buf, sizeof(fdt_buf));
-	if (err)
-		panic("Unable to open FDT: %d", err);
-
-	err = append_memory(fdt_buf);
-	if (err)
-		panic("Unable to patch FDT: %d", err);
-
-	err = remove_gic(fdt_buf);
-	if (err)
-		panic("Unable to patch FDT: %d", err);
-
-	err = serial_config(fdt_buf);
-	if (err)
-		panic("Unable to patch FDT: %d", err);
-
-	err = fdt_pack(fdt_buf);
-	if (err)
-		panic("Unable to pack FDT: %d\n", err);
-
-	return fdt_buf;
-}
diff --git a/arch/mips/mti-sead3/sead3-init.c b/arch/mips/mti-sead3/sead3-init.c
deleted file mode 100644
index 50f3fcb..0000000
--- a/arch/mips/mti-sead3/sead3-init.c
+++ /dev/null
@@ -1,100 +0,0 @@
-/*
- * 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) 2012 MIPS Technologies, Inc.  All rights reserved.
- */
-#include <linux/init.h>
-#include <linux/io.h>
-
-#include <asm/bootinfo.h>
-#include <asm/cacheflush.h>
-#include <asm/traps.h>
-#include <asm/mips-boards/generic.h>
-#include <asm/fw/fw.h>
-
-extern char except_vec_nmi;
-extern char except_vec_ejtag_debug;
-
-static void __init mips_nmi_setup(void)
-{
-	void *base;
-
-	base = cpu_has_veic ?
-		(void *)(CAC_BASE + 0xa80) :
-		(void *)(CAC_BASE + 0x380);
-#ifdef CONFIG_CPU_MICROMIPS
-	/*
-	 * Decrement the exception vector address by one for microMIPS.
-	 */
-	memcpy(base, (&except_vec_nmi - 1), 0x80);
-
-	/*
-	 * This is a hack. We do not know if the boot loader was built with
-	 * microMIPS instructions or not. If it was not, the NMI exception
-	 * code at 0x80000a80 will be taken in MIPS32 mode. The hand coded
-	 * assembly below forces us into microMIPS mode if we are a pure
-	 * microMIPS kernel. The assembly instructions are:
-	 *
-	 *  3C1A8000   lui       k0,0x8000
-	 *  375A0381   ori       k0,k0,0x381
-	 *  03400008   jr        k0
-	 *  00000000   nop
-	 *
-	 * The mode switch occurs by jumping to the unaligned exception
-	 * vector address at 0x80000381 which would have been 0x80000380
-	 * in MIPS32 mode. The jump to the unaligned address transitions
-	 * us into microMIPS mode.
-	 */
-	if (!cpu_has_veic) {
-		void *base2 = (void *)(CAC_BASE + 0xa80);
-		*((unsigned int *)base2) = 0x3c1a8000;
-		*((unsigned int *)base2 + 1) = 0x375a0381;
-		*((unsigned int *)base2 + 2) = 0x03400008;
-		*((unsigned int *)base2 + 3) = 0x00000000;
-		flush_icache_range((unsigned long)base2,
-			(unsigned long)base2 + 0x10);
-	}
-#else
-	memcpy(base, &except_vec_nmi, 0x80);
-#endif
-	flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
-}
-
-static void __init mips_ejtag_setup(void)
-{
-	void *base;
-
-	base = cpu_has_veic ?
-		(void *)(CAC_BASE + 0xa00) :
-		(void *)(CAC_BASE + 0x300);
-#ifdef CONFIG_CPU_MICROMIPS
-	/* Deja vu... */
-	memcpy(base, (&except_vec_ejtag_debug - 1), 0x80);
-	if (!cpu_has_veic) {
-		void *base2 = (void *)(CAC_BASE + 0xa00);
-		*((unsigned int *)base2) = 0x3c1a8000;
-		*((unsigned int *)base2 + 1) = 0x375a0301;
-		*((unsigned int *)base2 + 2) = 0x03400008;
-		*((unsigned int *)base2 + 3) = 0x00000000;
-		flush_icache_range((unsigned long)base2,
-			(unsigned long)base2 + 0x10);
-	}
-#else
-	memcpy(base, &except_vec_ejtag_debug, 0x80);
-#endif
-	flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
-}
-
-void __init prom_init(void)
-{
-	board_nmi_handler_setup = mips_nmi_setup;
-	board_ejtag_handler_setup = mips_ejtag_setup;
-
-	fw_init_cmdline();
-}
-
-void __init prom_free_prom_memory(void)
-{
-}
diff --git a/arch/mips/mti-sead3/sead3-int.c b/arch/mips/mti-sead3/sead3-int.c
deleted file mode 100644
index 2e6b732..0000000
--- a/arch/mips/mti-sead3/sead3-int.c
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * 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) 2012 MIPS Technologies, Inc.  All rights reserved.
- */
-#include <linux/init.h>
-#include <linux/irqchip.h>
-#include <linux/irqchip/mips-gic.h>
-
-#include <asm/cpu-info.h>
-#include <asm/irq.h>
-
-void __init arch_init_irq(void)
-{
-	irqchip_init();
-
-	pr_info("GIC: %spresent\n", (gic_present) ? "" : "not ");
-	pr_info("EIC: %s\n",
-		(current_cpu_data.options & MIPS_CPU_VEIC) ?  "on" : "off");
-}
-
diff --git a/arch/mips/mti-sead3/sead3-setup.c b/arch/mips/mti-sead3/sead3-setup.c
deleted file mode 100644
index c915e54..0000000
--- a/arch/mips/mti-sead3/sead3-setup.c
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * 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) 2012 MIPS Technologies, Inc.  All rights reserved.
- * Copyright (C) 2013 Imagination Technologies Ltd.
- */
-#include <linux/init.h>
-#include <linux/libfdt.h>
-#include <linux/of_fdt.h>
-
-#include <asm/prom.h>
-
-#include <asm/mach-sead3/sead3-dtshim.h>
-#include <asm/mips-boards/generic.h>
-
-const char *get_system_type(void)
-{
-	return "MIPS SEAD3";
-}
-
-void __init *plat_get_fdt(void)
-{
-	return (void *)__dtb_start;
-}
-
-void __init plat_mem_setup(void)
-{
-	void *fdt = plat_get_fdt();
-
-	fdt = sead3_dt_shim(fdt);
-	__dt_setup_arch(fdt);
-}
-
-void __init device_tree_init(void)
-{
-	unflatten_and_copy_device_tree();
-}
diff --git a/arch/mips/mti-sead3/sead3-time.c b/arch/mips/mti-sead3/sead3-time.c
deleted file mode 100644
index 71feb51..0000000
--- a/arch/mips/mti-sead3/sead3-time.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- * 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) 2012 MIPS Technologies, Inc.  All rights reserved.
- */
-#include <linux/init.h>
-#include <linux/irqchip/mips-gic.h>
-
-#include <asm/cpu.h>
-#include <asm/setup.h>
-#include <asm/time.h>
-#include <asm/irq.h>
-#include <asm/mips-boards/generic.h>
-
-static void __iomem *status_reg = (void __iomem *)0xbf000410;
-
-/*
- * Estimate CPU frequency.  Sets mips_hpt_frequency as a side-effect.
- */
-static unsigned int __init estimate_cpu_frequency(void)
-{
-	unsigned int prid = read_c0_prid() & (PRID_COMP_MASK | PRID_IMP_MASK);
-	unsigned int tick = 0;
-	unsigned int freq;
-	unsigned int orig;
-	unsigned long flags;
-
-	local_irq_save(flags);
-
-	orig = readl(status_reg) & 0x2;		      /* get original sample */
-	/* wait for transition */
-	while ((readl(status_reg) & 0x2) == orig)
-		;
-	orig = orig ^ 0x2;			      /* flip the bit */
-
-	write_c0_count(0);
-
-	/* wait 1 second (the sampling clock transitions every 10ms) */
-	while (tick < 100) {
-		/* wait for transition */
-		while ((readl(status_reg) & 0x2) == orig)
-			;
-		orig = orig ^ 0x2;			      /* flip the bit */
-		tick++;
-	}
-
-	freq = read_c0_count();
-
-	local_irq_restore(flags);
-
-	mips_hpt_frequency = freq;
-
-	/* Adjust for processor */
-	if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
-		(prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
-		freq *= 2;
-
-	freq += 5000;	     /* rounding */
-	freq -= freq%10000;
-
-	return freq ;
-}
-
-int get_c0_perfcount_int(void)
-{
-	if (gic_present)
-		return gic_get_c0_perfcount_int();
-	if (cp0_perfcount_irq >= 0)
-		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
-	return -1;
-}
-EXPORT_SYMBOL_GPL(get_c0_perfcount_int);
-
-unsigned int get_c0_compare_int(void)
-{
-	if (gic_present)
-		return gic_get_c0_compare_int();
-	return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
-}
-
-void __init plat_time_init(void)
-{
-	unsigned int est_freq;
-
-	est_freq = estimate_cpu_frequency();
-
-	pr_debug("CPU frequency %d.%02d MHz\n", (est_freq / 1000000),
-		(est_freq % 1000000) * 100 / 1000000);
-}