Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 237 insertions, 0 deletions

diff --git a/arch/ia64/kernel/patch.c b/arch/ia64/kernel/patch.c
new file mode 100644
index 000000000..7f21a8c57
--- /dev/null
+++ b/arch/ia64/kernel/patch.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Instruction-patching support.
+ *
+ * Copyright (C) 2003 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+#include <linux/init.h>
+#include <linux/string.h>
+
+#include <asm/patch.h>
+#include <asm/processor.h>
+#include <asm/sections.h>
+#include <asm/unistd.h>
+
+/*
+ * This was adapted from code written by Tony Luck:
+ *
+ * The 64-bit value in a "movl reg=value" is scattered between the two words of the bundle
+ * like this:
+ *
+ * 6  6         5         4         3         2         1
+ * 3210987654321098765432109876543210987654321098765432109876543210
+ * ABBBBBBBBBBBBBBBBBBBBBBBCCCCCCCCCCCCCCCCCCDEEEEEFFFFFFFFFGGGGGGG
+ *
+ * CCCCCCCCCCCCCCCCCCxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+ * xxxxAFFFFFFFFFEEEEEDxGGGGGGGxxxxxxxxxxxxxBBBBBBBBBBBBBBBBBBBBBBB
+ */
+static u64
+get_imm64 (u64 insn_addr)
+{
+	u64 *p = (u64 *) (insn_addr & -16);	/* mask out slot number */
+
+	return ( (p[1] & 0x0800000000000000UL) << 4)  | /*A*/
+		((p[1] & 0x00000000007fffffUL) << 40) | /*B*/
+		((p[0] & 0xffffc00000000000UL) >> 24) | /*C*/
+		((p[1] & 0x0000100000000000UL) >> 23) | /*D*/
+		((p[1] & 0x0003e00000000000UL) >> 29) | /*E*/
+		((p[1] & 0x07fc000000000000UL) >> 43) | /*F*/
+		((p[1] & 0x000007f000000000UL) >> 36);  /*G*/
+}
+
+/* Patch instruction with "val" where "mask" has 1 bits. */
+void
+ia64_patch (u64 insn_addr, u64 mask, u64 val)
+{
+	u64 m0, m1, v0, v1, b0, b1, *b = (u64 *) (insn_addr & -16);
+#	define insn_mask ((1UL << 41) - 1)
+	unsigned long shift;
+
+	b0 = b[0]; b1 = b[1];
+	shift = 5 + 41 * (insn_addr % 16); /* 5 bits of template, then 3 x 41-bit instructions */
+	if (shift >= 64) {
+		m1 = mask << (shift - 64);
+		v1 = val << (shift - 64);
+	} else {
+		m0 = mask << shift; m1 = mask >> (64 - shift);
+		v0 = val  << shift; v1 = val >> (64 - shift);
+		b[0] = (b0 & ~m0) | (v0 & m0);
+	}
+	b[1] = (b1 & ~m1) | (v1 & m1);
+}
+
+void
+ia64_patch_imm64 (u64 insn_addr, u64 val)
+{
+	/* The assembler may generate offset pointing to either slot 1
+	   or slot 2 for a long (2-slot) instruction, occupying slots 1
+	   and 2.  */
+  	insn_addr &= -16UL;
+	ia64_patch(insn_addr + 2,
+		   0x01fffefe000UL, (  ((val & 0x8000000000000000UL) >> 27) /* bit 63 -> 36 */
+				     | ((val & 0x0000000000200000UL) <<  0) /* bit 21 -> 21 */
+				     | ((val & 0x00000000001f0000UL) <<  6) /* bit 16 -> 22 */
+				     | ((val & 0x000000000000ff80UL) << 20) /* bit  7 -> 27 */
+				     | ((val & 0x000000000000007fUL) << 13) /* bit  0 -> 13 */));
+	ia64_patch(insn_addr + 1, 0x1ffffffffffUL, val >> 22);
+}
+
+void
+ia64_patch_imm60 (u64 insn_addr, u64 val)
+{
+	/* The assembler may generate offset pointing to either slot 1
+	   or slot 2 for a long (2-slot) instruction, occupying slots 1
+	   and 2.  */
+  	insn_addr &= -16UL;
+	ia64_patch(insn_addr + 2,
+		   0x011ffffe000UL, (  ((val & 0x0800000000000000UL) >> 23) /* bit 59 -> 36 */
+				     | ((val & 0x00000000000fffffUL) << 13) /* bit  0 -> 13 */));
+	ia64_patch(insn_addr + 1, 0x1fffffffffcUL, val >> 18);
+}
+
+/*
+ * We need sometimes to load the physical address of a kernel
+ * object.  Often we can convert the virtual address to physical
+ * at execution time, but sometimes (either for performance reasons
+ * or during error recovery) we cannot to this.  Patch the marked
+ * bundles to load the physical address.
+ */
+void __init
+ia64_patch_vtop (unsigned long start, unsigned long end)
+{
+	s32 *offp = (s32 *) start;
+	u64 ip;
+
+	while (offp < (s32 *) end) {
+		ip = (u64) offp + *offp;
+
+		/* replace virtual address with corresponding physical address: */
+		ia64_patch_imm64(ip, ia64_tpa(get_imm64(ip)));
+		ia64_fc((void *) ip);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}
+
+/*
+ * Disable the RSE workaround by turning the conditional branch
+ * that we tagged in each place the workaround was used into an
+ * unconditional branch.
+ */
+void __init
+ia64_patch_rse (unsigned long start, unsigned long end)
+{
+	s32 *offp = (s32 *) start;
+	u64 ip, *b;
+
+	while (offp < (s32 *) end) {
+		ip = (u64) offp + *offp;
+
+		b = (u64 *)(ip & -16);
+		b[1] &= ~0xf800000L;
+		ia64_fc((void *) ip);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}
+
+void __init
+ia64_patch_mckinley_e9 (unsigned long start, unsigned long end)
+{
+	static int first_time = 1;
+	int need_workaround;
+	s32 *offp = (s32 *) start;
+	u64 *wp;
+
+	need_workaround = (local_cpu_data->family == 0x1f && local_cpu_data->model == 0);
+
+	if (first_time) {
+		first_time = 0;
+		if (need_workaround)
+			printk(KERN_INFO "Leaving McKinley Errata 9 workaround enabled\n");
+	}
+	if (need_workaround)
+		return;
+
+	while (offp < (s32 *) end) {
+		wp = (u64 *) ia64_imva((char *) offp + *offp);
+		wp[0] = 0x0000000100000011UL; /* nop.m 0; nop.i 0; br.ret.sptk.many b6 */
+		wp[1] = 0x0084006880000200UL;
+		wp[2] = 0x0000000100000000UL; /* nop.m 0; nop.i 0; nop.i 0 */
+		wp[3] = 0x0004000000000200UL;
+		ia64_fc(wp); ia64_fc(wp + 2);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}
+
+static void __init
+patch_fsyscall_table (unsigned long start, unsigned long end)
+{
+	extern unsigned long fsyscall_table[NR_syscalls];
+	s32 *offp = (s32 *) start;
+	u64 ip;
+
+	while (offp < (s32 *) end) {
+		ip = (u64) ia64_imva((char *) offp + *offp);
+		ia64_patch_imm64(ip, (u64) fsyscall_table);
+		ia64_fc((void *) ip);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}
+
+static void __init
+patch_brl_fsys_bubble_down (unsigned long start, unsigned long end)
+{
+	extern char fsys_bubble_down[];
+	s32 *offp = (s32 *) start;
+	u64 ip;
+
+	while (offp < (s32 *) end) {
+		ip = (u64) offp + *offp;
+		ia64_patch_imm60((u64) ia64_imva((void *) ip),
+				 (u64) (fsys_bubble_down - (ip & -16)) / 16);
+		ia64_fc((void *) ip);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}
+
+void __init
+ia64_patch_gate (void)
+{
+#	define START(name)	((unsigned long) __start_gate_##name##_patchlist)
+#	define END(name)	((unsigned long)__end_gate_##name##_patchlist)
+
+	patch_fsyscall_table(START(fsyscall), END(fsyscall));
+	patch_brl_fsys_bubble_down(START(brl_fsys_bubble_down), END(brl_fsys_bubble_down));
+	ia64_patch_vtop(START(vtop), END(vtop));
+	ia64_patch_mckinley_e9(START(mckinley_e9), END(mckinley_e9));
+}
+
+void ia64_patch_phys_stack_reg(unsigned long val)
+{
+	s32 * offp = (s32 *) __start___phys_stack_reg_patchlist;
+	s32 * end = (s32 *) __end___phys_stack_reg_patchlist;
+	u64 ip, mask, imm;
+
+	/* see instruction format A4: adds r1 = imm13, r3 */
+	mask = (0x3fUL << 27) | (0x7f << 13);
+	imm = (((val >> 7) & 0x3f) << 27) | (val & 0x7f) << 13;
+
+	while (offp < end) {
+		ip = (u64) offp + *offp;
+		ia64_patch(ip, mask, imm);
+		ia64_fc((void *)ip);
+		++offp;
+	}
+	ia64_sync_i();
+	ia64_srlz_i();
+}