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-rw-r--r--arch/mips/kernel/cpu-bugs64.c325
1 files changed, 0 insertions, 325 deletions
diff --git a/arch/mips/kernel/cpu-bugs64.c b/arch/mips/kernel/cpu-bugs64.c
deleted file mode 100644
index 6a7afe7ef4d3..000000000000
--- a/arch/mips/kernel/cpu-bugs64.c
+++ /dev/null
@@ -1,325 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2003, 2004, 2007 Maciej W. Rozycki
- */
-#include <linux/context_tracking.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/ptrace.h>
-#include <linux/stddef.h>
-
-#include <asm/bugs.h>
-#include <asm/compiler.h>
-#include <asm/cpu.h>
-#include <asm/fpu.h>
-#include <asm/mipsregs.h>
-#include <asm/setup.h>
-
-static char bug64hit[] __initdata =
- "reliable operation impossible!\n%s";
-static char nowar[] __initdata =
- "Please report to <linux-mips@linux-mips.org>.";
-static char r4kwar[] __initdata =
- "Enable CPU_R4000_WORKAROUNDS to rectify.";
-static char daddiwar[] __initdata =
- "Enable CPU_DADDI_WORKAROUNDS to rectify.";
-
-static __always_inline __init
-void align_mod(const int align, const int mod)
-{
- asm volatile(
- ".set push\n\t"
- ".set noreorder\n\t"
- ".balign %0\n\t"
- ".rept %1\n\t"
- "nop\n\t"
- ".endr\n\t"
- ".set pop"
- :
- : "n"(align), "n"(mod));
-}
-
-static __always_inline __init
-void mult_sh_align_mod(long *v1, long *v2, long *w,
- const int align, const int mod)
-{
- unsigned long flags;
- int m1, m2;
- long p, s, lv1, lv2, lw;
-
- /*
- * We want the multiply and the shift to be isolated from the
- * rest of the code to disable gcc optimizations. Hence the
- * asm statements that execute nothing, but make gcc not know
- * what the values of m1, m2 and s are and what lv2 and p are
- * used for.
- */
-
- local_irq_save(flags);
- /*
- * The following code leads to a wrong result of the first
- * dsll32 when executed on R4000 rev. 2.2 or 3.0 (PRId
- * 00000422 or 00000430, respectively).
- *
- * See "MIPS R4000PC/SC Errata, Processor Revision 2.2 and
- * 3.0" by MIPS Technologies, Inc., errata #16 and #28 for
- * details. I got no permission to duplicate them here,
- * sigh... --macro
- */
- asm volatile(
- ""
- : "=r" (m1), "=r" (m2), "=r" (s)
- : "0" (5), "1" (8), "2" (5));
- align_mod(align, mod);
- /*
- * The trailing nop is needed to fulfill the two-instruction
- * requirement between reading hi/lo and staring a mult/div.
- * Leaving it out may cause gas insert a nop itself breaking
- * the desired alignment of the next chunk.
- */
- asm volatile(
- ".set push\n\t"
- ".set noat\n\t"
- ".set noreorder\n\t"
- ".set nomacro\n\t"
- "mult %2, %3\n\t"
- "dsll32 %0, %4, %5\n\t"
- "mflo $0\n\t"
- "dsll32 %1, %4, %5\n\t"
- "nop\n\t"
- ".set pop"
- : "=&r" (lv1), "=r" (lw)
- : "r" (m1), "r" (m2), "r" (s), "I" (0)
- : "hi", "lo", "$0");
- /* We have to use single integers for m1 and m2 and a double
- * one for p to be sure the mulsidi3 gcc's RTL multiplication
- * instruction has the workaround applied. Older versions of
- * gcc have correct umulsi3 and mulsi3, but other
- * multiplication variants lack the workaround.
- */
- asm volatile(
- ""
- : "=r" (m1), "=r" (m2), "=r" (s)
- : "0" (m1), "1" (m2), "2" (s));
- align_mod(align, mod);
- p = m1 * m2;
- lv2 = s << 32;
- asm volatile(
- ""
- : "=r" (lv2)
- : "0" (lv2), "r" (p));
- local_irq_restore(flags);
-
- *v1 = lv1;
- *v2 = lv2;
- *w = lw;
-}
-
-static __always_inline __init void check_mult_sh(void)
-{
- long v1[8], v2[8], w[8];
- int bug, fix, i;
-
- printk("Checking for the multiply/shift bug... ");
-
- /*
- * Testing discovered false negatives for certain code offsets
- * into cache lines. Hence we test all possible offsets for
- * the worst assumption of an R4000 I-cache line width of 32
- * bytes.
- *
- * We can't use a loop as alignment directives need to be
- * immediates.
- */
- mult_sh_align_mod(&v1[0], &v2[0], &w[0], 32, 0);
- mult_sh_align_mod(&v1[1], &v2[1], &w[1], 32, 1);
- mult_sh_align_mod(&v1[2], &v2[2], &w[2], 32, 2);
- mult_sh_align_mod(&v1[3], &v2[3], &w[3], 32, 3);
- mult_sh_align_mod(&v1[4], &v2[4], &w[4], 32, 4);
- mult_sh_align_mod(&v1[5], &v2[5], &w[5], 32, 5);
- mult_sh_align_mod(&v1[6], &v2[6], &w[6], 32, 6);
- mult_sh_align_mod(&v1[7], &v2[7], &w[7], 32, 7);
-
- bug = 0;
- for (i = 0; i < 8; i++)
- if (v1[i] != w[i])
- bug = 1;
-
- if (bug == 0) {
- pr_cont("no.\n");
- return;
- }
-
- pr_cont("yes, workaround... ");
-
- fix = 1;
- for (i = 0; i < 8; i++)
- if (v2[i] != w[i])
- fix = 0;
-
- if (fix == 1) {
- pr_cont("yes.\n");
- return;
- }
-
- pr_cont("no.\n");
- panic(bug64hit, !R4000_WAR ? r4kwar : nowar);
-}
-
-static volatile int daddi_ov;
-
-asmlinkage void __init do_daddi_ov(struct pt_regs *regs)
-{
- enum ctx_state prev_state;
-
- prev_state = exception_enter();
- daddi_ov = 1;
- regs->cp0_epc += 4;
- exception_exit(prev_state);
-}
-
-static __init void check_daddi(void)
-{
- extern asmlinkage void handle_daddi_ov(void);
- unsigned long flags;
- void *handler;
- long v, tmp;
-
- printk("Checking for the daddi bug... ");
-
- local_irq_save(flags);
- handler = set_except_vector(EXCCODE_OV, handle_daddi_ov);
- /*
- * The following code fails to trigger an overflow exception
- * when executed on R4000 rev. 2.2 or 3.0 (PRId 00000422 or
- * 00000430, respectively).
- *
- * See "MIPS R4000PC/SC Errata, Processor Revision 2.2 and
- * 3.0" by MIPS Technologies, Inc., erratum #23 for details.
- * I got no permission to duplicate it here, sigh... --macro
- */
- asm volatile(
- ".set push\n\t"
- ".set noat\n\t"
- ".set noreorder\n\t"
- ".set nomacro\n\t"
- "addiu %1, $0, %2\n\t"
- "dsrl %1, %1, 1\n\t"
-#ifdef HAVE_AS_SET_DADDI
- ".set daddi\n\t"
-#endif
- "daddi %0, %1, %3\n\t"
- ".set pop"
- : "=r" (v), "=&r" (tmp)
- : "I" (0xffffffffffffdb9aUL), "I" (0x1234));
- set_except_vector(EXCCODE_OV, handler);
- local_irq_restore(flags);
-
- if (daddi_ov) {
- pr_cont("no.\n");
- return;
- }
-
- pr_cont("yes, workaround... ");
-
- local_irq_save(flags);
- handler = set_except_vector(EXCCODE_OV, handle_daddi_ov);
- asm volatile(
- "addiu %1, $0, %2\n\t"
- "dsrl %1, %1, 1\n\t"
- "daddi %0, %1, %3"
- : "=r" (v), "=&r" (tmp)
- : "I" (0xffffffffffffdb9aUL), "I" (0x1234));
- set_except_vector(EXCCODE_OV, handler);
- local_irq_restore(flags);
-
- if (daddi_ov) {
- pr_cont("yes.\n");
- return;
- }
-
- pr_cont("no.\n");
- panic(bug64hit, !DADDI_WAR ? daddiwar : nowar);
-}
-
-int daddiu_bug = IS_ENABLED(CONFIG_CPU_MIPSR6) ? 0 : -1;
-
-static __init void check_daddiu(void)
-{
- long v, w, tmp;
-
- printk("Checking for the daddiu bug... ");
-
- /*
- * The following code leads to a wrong result of daddiu when
- * executed on R4400 rev. 1.0 (PRId 00000440).
- *
- * See "MIPS R4400PC/SC Errata, Processor Revision 1.0" by
- * MIPS Technologies, Inc., erratum #7 for details.
- *
- * According to "MIPS R4000PC/SC Errata, Processor Revision
- * 2.2 and 3.0" by MIPS Technologies, Inc., erratum #41 this
- * problem affects R4000 rev. 2.2 and 3.0 (PRId 00000422 and
- * 00000430, respectively), too. Testing failed to trigger it
- * so far.
- *
- * I got no permission to duplicate the errata here, sigh...
- * --macro
- */
- asm volatile(
- ".set push\n\t"
- ".set noat\n\t"
- ".set noreorder\n\t"
- ".set nomacro\n\t"
- "addiu %2, $0, %3\n\t"
- "dsrl %2, %2, 1\n\t"
-#ifdef HAVE_AS_SET_DADDI
- ".set daddi\n\t"
-#endif
- "daddiu %0, %2, %4\n\t"
- "addiu %1, $0, %4\n\t"
- "daddu %1, %2\n\t"
- ".set pop"
- : "=&r" (v), "=&r" (w), "=&r" (tmp)
- : "I" (0xffffffffffffdb9aUL), "I" (0x1234));
-
- daddiu_bug = v != w;
-
- if (!daddiu_bug) {
- pr_cont("no.\n");
- return;
- }
-
- pr_cont("yes, workaround... ");
-
- asm volatile(
- "addiu %2, $0, %3\n\t"
- "dsrl %2, %2, 1\n\t"
- "daddiu %0, %2, %4\n\t"
- "addiu %1, $0, %4\n\t"
- "daddu %1, %2"
- : "=&r" (v), "=&r" (w), "=&r" (tmp)
- : "I" (0xffffffffffffdb9aUL), "I" (0x1234));
-
- if (v == w) {
- pr_cont("yes.\n");
- return;
- }
-
- pr_cont("no.\n");
- panic(bug64hit, !DADDI_WAR ? daddiwar : nowar);
-}
-
-void __init check_bugs64_early(void)
-{
- if (!IS_ENABLED(CONFIG_CPU_MIPSR6)) {
- check_mult_sh();
- check_daddiu();
- }
-}
-
-void __init check_bugs64(void)
-{
- if (!IS_ENABLED(CONFIG_CPU_MIPSR6))
- check_daddi();
-}