diff options
Diffstat (limited to 'arch/arm/kernel/pj4-cp0.c')
-rw-r--r-- | arch/arm/kernel/pj4-cp0.c | 135 |
1 files changed, 0 insertions, 135 deletions
diff --git a/arch/arm/kernel/pj4-cp0.c b/arch/arm/kernel/pj4-cp0.c deleted file mode 100644 index 4bca8098c4ff..000000000000 --- a/arch/arm/kernel/pj4-cp0.c +++ /dev/null @@ -1,135 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * linux/arch/arm/kernel/pj4-cp0.c - * - * PJ4 iWMMXt coprocessor context switching and handling - * - * Copyright (c) 2010 Marvell International Inc. - */ - -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/signal.h> -#include <linux/sched.h> -#include <linux/init.h> -#include <linux/io.h> -#include <asm/thread_notify.h> -#include <asm/cputype.h> - -static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t) -{ - struct thread_info *thread = t; - - switch (cmd) { - case THREAD_NOTIFY_FLUSH: - /* - * flush_thread() zeroes thread->fpstate, so no need - * to do anything here. - * - * FALLTHROUGH: Ensure we don't try to overwrite our newly - * initialised state information on the first fault. - */ - - case THREAD_NOTIFY_EXIT: - iwmmxt_task_release(thread); - break; - - case THREAD_NOTIFY_SWITCH: - iwmmxt_task_switch(thread); - break; - } - - return NOTIFY_DONE; -} - -static struct notifier_block __maybe_unused iwmmxt_notifier_block = { - .notifier_call = iwmmxt_do, -}; - - -static u32 __init pj4_cp_access_read(void) -{ - u32 value; - - __asm__ __volatile__ ( - "mrc p15, 0, %0, c1, c0, 2\n\t" - : "=r" (value)); - return value; -} - -static void __init pj4_cp_access_write(u32 value) -{ - u32 temp; - - __asm__ __volatile__ ( - "mcr p15, 0, %1, c1, c0, 2\n\t" -#ifdef CONFIG_THUMB2_KERNEL - "isb\n\t" -#else - "mrc p15, 0, %0, c1, c0, 2\n\t" - "mov %0, %0\n\t" - "sub pc, pc, #4\n\t" -#endif - : "=r" (temp) : "r" (value)); -} - -static int __init pj4_get_iwmmxt_version(void) -{ - u32 cp_access, wcid; - - cp_access = pj4_cp_access_read(); - pj4_cp_access_write(cp_access | 0xf); - - /* check if coprocessor 0 and 1 are available */ - if ((pj4_cp_access_read() & 0xf) != 0xf) { - pj4_cp_access_write(cp_access); - return -ENODEV; - } - - /* read iWMMXt coprocessor id register p1, c0 */ - __asm__ __volatile__ ("mrc p1, 0, %0, c0, c0, 0\n" : "=r" (wcid)); - - pj4_cp_access_write(cp_access); - - /* iWMMXt v1 */ - if ((wcid & 0xffffff00) == 0x56051000) - return 1; - /* iWMMXt v2 */ - if ((wcid & 0xffffff00) == 0x56052000) - return 2; - - return -EINVAL; -} - -/* - * Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy - * switch code handle iWMMXt context switching. - */ -static int __init pj4_cp0_init(void) -{ - u32 __maybe_unused cp_access; - int vers; - - if (!cpu_is_pj4()) - return 0; - - vers = pj4_get_iwmmxt_version(); - if (vers < 0) - return 0; - -#ifndef CONFIG_IWMMXT - pr_info("PJ4 iWMMXt coprocessor detected, but kernel support is missing.\n"); -#else - cp_access = pj4_cp_access_read() & ~0xf; - pj4_cp_access_write(cp_access); - - pr_info("PJ4 iWMMXt v%d coprocessor enabled.\n", vers); - elf_hwcap |= HWCAP_IWMMXT; - thread_register_notifier(&iwmmxt_notifier_block); - register_iwmmxt_undef_handler(); -#endif - - return 0; -} - -late_initcall(pj4_cp0_init); |