From 4e74ae800bafe79d4aaa529bc5d52425757c0115 Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@sunset.davemloft.net>
Date: Mon, 20 Feb 2006 16:02:24 -0800
Subject: [PATCH] [SPARC64]: Handle unimplemented FPU square-root on Niagara.
The math-emu code only expects unfinished fpop traps when
emulating FPU sqrt instructions on pre-Niagara chips.
On Niagara we can get unimplemented fpop, so handle that.
Signed-off-by: David S. Miller <davem@davemloft.net>
---
arch/sparc64/math-emu/math.c | 25 +++++++++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/arch/sparc64/math-emu/math.c b/arch/sparc64/math-emu/math.c
index 2ae05cd7b773f..a93a3664c8545 100644
--- a/arch/sparc64/math-emu/math.c
+++ b/arch/sparc64/math-emu/math.c
@@ -206,9 +206,30 @@ int do_mathemu(struct pt_regs *regs, struct fpustate *f)
case FSTOQ: TYPE(3,3,1,1,1,0,0); break;
case FDTOQ: TYPE(3,3,1,2,1,0,0); break;
case FQTOI: TYPE(3,1,0,3,1,0,0); break;
+
+ /* We can get either unimplemented or unfinished
+ * for these cases. Pre-Niagara systems generate
+ * unfinished fpop for SUBNORMAL cases, and Niagara
+ * always gives unimplemented fpop for fsqrt{s,d}.
+ */
+ case FSQRTS: {
+ unsigned long x = current_thread_info()->xfsr[0];
+
+ x = (x >> 14) & 0xf;
+ TYPE(x,1,1,1,1,0,0);
+ printk("math-emu: type is %08x\n", type);
+ break;
+ }
+
+ case FSQRTD: {
+ unsigned long x = current_thread_info()->xfsr[0];
+
+ x = (x >> 14) & 0xf;
+ TYPE(x,2,1,2,1,0,0);
+ break;
+ }
+
/* SUBNORMAL - ftt == 2 */
- case FSQRTS: TYPE(2,1,1,1,1,0,0); break;
- case FSQRTD: TYPE(2,2,1,2,1,0,0); break;
case FADDD:
case FSUBD:
case FMULD:
--
GitLab