* Copyright (C) 1994, 95, 96, 99, 2001 Ralf Baechle
* Copyright (C) 1994, 1995, 1996 Paul M. Antoine.
* Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2007 Maciej W. Rozycki
*/
#ifndef _ASM_STACKFRAME_H
#define _ASM_STACKFRAME_H
#else
MFC0 k0, CP0_CONTEXT
#endif
-#if defined(CONFIG_BUILD_ELF64) || (defined(CONFIG_64BIT) && __GNUC__ < 4)
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
+ lui k1, %hi(kernelsp)
+#else
lui k1, %highest(kernelsp)
daddiu k1, %higher(kernelsp)
dsll k1, 16
daddiu k1, %hi(kernelsp)
dsll k1, 16
-#else
- lui k1, %hi(kernelsp)
#endif
LONG_SRL k0, PTEBASE_SHIFT
LONG_ADDU k1, k0
.endm
#else
.macro get_saved_sp /* Uniprocessor variation */
-#if defined(CONFIG_BUILD_ELF64) || (defined(CONFIG_64BIT) && __GNUC__ < 4)
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
+ lui k1, %hi(kernelsp)
+#else
lui k1, %highest(kernelsp)
daddiu k1, %higher(kernelsp)
dsll k1, k1, 16
daddiu k1, %hi(kernelsp)
dsll k1, k1, 16
-#else
- lui k1, %hi(kernelsp)
#endif
LONG_L k1, %lo(kernelsp)(k1)
.endm
.set reorder
/* Called from user mode, new stack. */
get_saved_sp
+#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
8: move k0, sp
PTR_SUBU sp, k1, PT_SIZE
+#else
+ .set at=k0
+8: PTR_SUBU k1, PT_SIZE
+ .set noat
+ move k0, sp
+ move sp, k1
+#endif
LONG_S k0, PT_R29(sp)
LONG_S $3, PT_R3(sp)
/*
#ifdef CONFIG_MIPS_MT_SMTC
.set mips32r2
/*
- * This may not really be necessary if ints are already
- * inhibited here.
+ * We need to make sure the read-modify-write
+ * of Status below isn't perturbed by an interrupt
+ * or cross-TC access, so we need to do at least a DMT,
+ * protected by an interrupt-inhibit. But setting IXMT
+ * also creates a few-cycle window where an IPI could
+ * be queued and not be detected before potentially
+ * returning to a WAIT or user-mode loop. It must be
+ * replayed.
+ *
+ * We're in the middle of a context switch, and
+ * we can't dispatch it directly without trashing
+ * some registers, so we'll try to detect this unlikely
+ * case and program a software interrupt in the VPE,
+ * as would be done for a cross-VPE IPI. To accomodate
+ * the handling of that case, we're doing a DVPE instead
+ * of just a DMT here to protect against other threads.
+ * This is a lot of cruft to cover a tiny window.
+ * If you can find a better design, implement it!
+ *
*/
mfc0 v0, CP0_TCSTATUS
ori v0, TCSTATUS_IXMT
mtc0 v0, CP0_TCSTATUS
_ehb
- DMT 5 # dmt a1
+ DVPE 5 # dvpe a1
jal mips_ihb
#endif /* CONFIG_MIPS_MT_SMTC */
mfc0 a0, CP0_STATUS
*/
LONG_L v1, PT_TCSTATUS(sp)
_ehb
- mfc0 v0, CP0_TCSTATUS
+ mfc0 a0, CP0_TCSTATUS
andi v1, TCSTATUS_IXMT
- /* We know that TCStatua.IXMT should be set from above */
- xori v0, v0, TCSTATUS_IXMT
- or v0, v0, v1
- mtc0 v0, CP0_TCSTATUS
- _ehb
- andi a1, a1, VPECONTROL_TE
+ bnez v1, 0f
+
+/*
+ * We'd like to detect any IPIs queued in the tiny window
+ * above and request an software interrupt to service them
+ * when we ERET.
+ *
+ * Computing the offset into the IPIQ array of the executing
+ * TC's IPI queue in-line would be tedious. We use part of
+ * the TCContext register to hold 16 bits of offset that we
+ * can add in-line to find the queue head.
+ */
+ mfc0 v0, CP0_TCCONTEXT
+ la a2, IPIQ
+ srl v0, v0, 16
+ addu a2, a2, v0
+ LONG_L v0, 0(a2)
+ beqz v0, 0f
+/*
+ * If we have a queue, provoke dispatch within the VPE by setting C_SW1
+ */
+ mfc0 v0, CP0_CAUSE
+ ori v0, v0, C_SW1
+ mtc0 v0, CP0_CAUSE
+0:
+ /*
+ * This test should really never branch but
+ * let's be prudent here. Having atomized
+ * the shared register modifications, we can
+ * now EVPE, and must do so before interrupts
+ * are potentially re-enabled.
+ */
+ andi a1, a1, MVPCONTROL_EVP
beqz a1, 1f
- emt
+ evpe
1:
+ /* We know that TCStatua.IXMT should be set from above */
+ xori a0, a0, TCSTATUS_IXMT
+ or a0, a0, v1
+ mtc0 a0, CP0_TCSTATUS
+ _ehb
+
.set mips0
#endif /* CONFIG_MIPS_MT_SMTC */
LONG_L v1, PT_EPC(sp)
* and disable interrupts only for the
* current TC, using the TCStatus register.
*/
- mfc0 t0,CP0_TCSTATUS
+ mfc0 t0, CP0_TCSTATUS
/* Fortunately CU 0 is in the same place in both registers */
/* Set TCU0, TMX, TKSU (for later inversion) and IXMT */
li t1, ST0_CU0 | 0x08001c00
- or t0,t1
+ or t0, t1
/* Clear TKSU, leave IXMT */
xori t0, 0x00001800
mtc0 t0, CP0_TCSTATUS
* current TC, using the TCStatus register.
*/
_ehb
- mfc0 t0,CP0_TCSTATUS
+ mfc0 t0, CP0_TCSTATUS
/* Fortunately CU 0 is in the same place in both registers */
/* Set TCU0, TKSU (for later inversion) and IXMT */
li t1, ST0_CU0 | 0x08001c00
- or t0,t1
+ or t0, t1
/* Clear TKSU *and* IXMT */
xori t0, 0x00001c00
mtc0 t0, CP0_TCSTATUS
git.openpandora.org / pandora-kernel.git / blobdiff