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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/sparc/kernel/devices.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/sparc/kernel/devices.c')
-rw-r--r-- | arch/sparc/kernel/devices.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/sparc/kernel/devices.c b/arch/sparc/kernel/devices.c new file mode 100644 index 000000000..23b6e50d4 --- /dev/null +++ b/arch/sparc/kernel/devices.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +/* devices.c: Initial scan of the prom device tree for important + * Sparc device nodes which we need to find. + * + * This is based on the sparc64 version, but sun4m doesn't always use + * the hardware MIDs, so be careful. + * + * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) + */ + +#include <linux/kernel.h> +#include <linux/threads.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/errno.h> + +#include <asm/page.h> +#include <asm/oplib.h> +#include <asm/prom.h> +#include <asm/smp.h> +#include <asm/cpudata.h> +#include <asm/cpu_type.h> +#include <asm/setup.h> + +#include "kernel.h" + +static char *cpu_mid_prop(void) +{ + if (sparc_cpu_model == sun4d) + return "cpu-id"; + return "mid"; +} + +static int check_cpu_node(phandle nd, int *cur_inst, + int (*compare)(phandle, int, void *), void *compare_arg, + phandle *prom_node, int *mid) +{ + if (!compare(nd, *cur_inst, compare_arg)) { + if (prom_node) + *prom_node = nd; + if (mid) { + *mid = prom_getintdefault(nd, cpu_mid_prop(), 0); + if (sparc_cpu_model == sun4m) + *mid &= 3; + } + return 0; + } + + (*cur_inst)++; + + return -ENODEV; +} + +static int __cpu_find_by(int (*compare)(phandle, int, void *), + void *compare_arg, phandle *prom_node, int *mid) +{ + struct device_node *dp; + int cur_inst; + + cur_inst = 0; + for_each_node_by_type(dp, "cpu") { + int err = check_cpu_node(dp->phandle, &cur_inst, + compare, compare_arg, + prom_node, mid); + if (!err) { + of_node_put(dp); + return 0; + } + } + + return -ENODEV; +} + +static int cpu_instance_compare(phandle nd, int instance, void *_arg) +{ + int desired_instance = (int) _arg; + + if (instance == desired_instance) + return 0; + return -ENODEV; +} + +int cpu_find_by_instance(int instance, phandle *prom_node, int *mid) +{ + return __cpu_find_by(cpu_instance_compare, (void *)instance, + prom_node, mid); +} + +static int cpu_mid_compare(phandle nd, int instance, void *_arg) +{ + int desired_mid = (int) _arg; + int this_mid; + + this_mid = prom_getintdefault(nd, cpu_mid_prop(), 0); + if (this_mid == desired_mid + || (sparc_cpu_model == sun4m && (this_mid & 3) == desired_mid)) + return 0; + return -ENODEV; +} + +int cpu_find_by_mid(int mid, phandle *prom_node) +{ + return __cpu_find_by(cpu_mid_compare, (void *)mid, + prom_node, NULL); +} + +/* sun4m uses truncated mids since we base the cpuid on the ttable/irqset + * address (0-3). This gives us the true hardware mid, which might have + * some other bits set. On 4d hardware and software mids are the same. + */ +int cpu_get_hwmid(phandle prom_node) +{ + return prom_getintdefault(prom_node, cpu_mid_prop(), -ENODEV); +} + +void __init device_scan(void) +{ + printk(KERN_NOTICE "Booting Linux...\n"); + +#ifndef CONFIG_SMP + { + phandle cpu_node; + int err; + err = cpu_find_by_instance(0, &cpu_node, NULL); + if (err) { + /* Probably a sun4e, Sun is trying to trick us ;-) */ + prom_printf("No cpu nodes, cannot continue\n"); + prom_halt(); + } + cpu_data(0).clock_tick = prom_getintdefault(cpu_node, + "clock-frequency", + 0); + } +#endif /* !CONFIG_SMP */ + + auxio_probe(); + auxio_power_probe(); +} |