[src/trunk]: src/sys/arch/arm/vfp In the REENABLE case, make sur the fpexc co...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fc0f633f6e11
branches:  trunk
changeset: 827142:fc0f633f6e11
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Mon Oct 16 15:08:24 2017 +0000

description:
In the REENABLE case, make sur the fpexc copy in the pcb also has
VFP_FPEXC_EN set. Otherwise we could trap on every context switch even if
the CPU already has the VFP state.

diffstat:

 sys/arch/arm/vfp/vfp_init.c |  10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

diffs (46 lines):

diff -r 29ef663c03d3 -r fc0f633f6e11 sys/arch/arm/vfp/vfp_init.c
--- a/sys/arch/arm/vfp/vfp_init.c       Mon Oct 16 15:03:57 2017 +0000
+++ b/sys/arch/arm/vfp/vfp_init.c       Mon Oct 16 15:08:24 2017 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: vfp_init.c,v 1.53 2017/05/26 21:17:46 jmcneill Exp $ */
+/*      $NetBSD: vfp_init.c,v 1.54 2017/10/16 15:08:24 bouyer Exp $ */
 
 /*
  * Copyright (c) 2008 ARM Ltd
@@ -520,14 +520,17 @@
                curcpu()->ci_vfp_evs[1].ev_count++;
        }
 
+       KASSERT((armreg_fpexc_read() & VFP_FPEXC_EN) == 0);
        /*
         * If the VFP is already enabled we must be bouncing an instruction.
         */
        if (flags & PCU_REENABLE) {
                uint32_t fpexc = armreg_fpexc_read();
                armreg_fpexc_write(fpexc | VFP_FPEXC_EN);
+               fregs->vfp_fpexc |= VFP_FPEXC_EN;
                return;
        }
+       KASSERT((fregs->vfp_fpexc & VFP_FPEXC_EN) == 0);
 
        /*
         * Load and Enable the VFP (so that we can write the registers).
@@ -543,6 +546,8 @@
                 */
                return;
        }
+       KASSERT(curcpu()->ci_pcu_curlwp[PCU_FPU] == NULL);
+       KASSERT(l->l_pcu_cpu[PCU_FPU] == NULL);
 
        load_vfpregs(fregs);
        armreg_fpscr_write(fregs->vfp_fpscr);
@@ -562,6 +567,9 @@
        struct vfpreg * const fregs = &pcb->pcb_vfp;
        uint32_t fpexc = armreg_fpexc_read();
 
+       KASSERT(curcpu()->ci_pcu_curlwp[PCU_FPU] == l);
+       KASSERT(curcpu() == l->l_pcu_cpu[PCU_FPU]);
+       KASSERT(curlwp == l || curlwp->l_pcu_cpu[PCU_FPU] != curcpu());
        /*
         * Enable the VFP (so we can read the registers).
         * Make sure the exception bit is cleared so that we can