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Diffstat (limited to 'arch/arm/kernel/pj4-cp0.c')
-rw-r--r--arch/arm/kernel/pj4-cp0.c135
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);