MN10300: AM34 erratum requires MMUCTR read and write on exception entry
authorAkira Takeuchi <takeuchi.akr@jp.panasonic.com>
Wed, 27 Oct 2010 16:28:48 +0000 (17:28 +0100)
committerDavid Howells <dhowells@redhat.com>
Wed, 27 Oct 2010 16:28:48 +0000 (17:28 +0100)
An AM34 erratum requires MMUCTR read and write on entry to certain exceptions,
prior to EPSW.NMID being cleared to allow NMIs to happen.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
arch/mn10300/Kconfig
arch/mn10300/kernel/entry.S
arch/mn10300/mm/tlb-mn10300.S

index 21e2a534d98ef9f0b283be2f193e68c2609e0b04..dd7b5700358b04588d0769ec96bcc5684887e288 100644 (file)
@@ -20,6 +20,9 @@ config AM34_2
        select MN10300_HAS_ATOMIC_OPS_UNIT
        select MN10300_HAS_CACHE_SNOOP
 
+config ERRATUM_NEED_TO_RELOAD_MMUCTR
+       def_bool y if AM33_3 || AM34_2
+
 config MMU
        def_bool y
 
index b82ce7b47fcbba4b2b49d5a28aad16f1edf8ef20..355f681767713404416b2f754893554778eb4ced 100644 (file)
@@ -251,6 +251,10 @@ double_fault_loop:
 ENTRY(raw_bus_error)
        add     -4,sp
        mov     d0,(sp)
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d0
+       mov     d0,(MMUCTR)
+#endif
        mov     (BCBERR),d0             # what
        btst    BCBERR_BEMR_DMA,d0      # see if it was an external bus error
        beq     __common_exception_aux  # it wasn't
@@ -282,6 +286,10 @@ ENTRY(nmi_handler)
 ENTRY(__common_exception)
        add     -4,sp
        mov     d0,(sp)
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d0
+       mov     d0,(MMUCTR)
+#endif
 
 __common_exception_aux:
        mov     (TBR),d0
index 7095147dcb8ba2f83bbad869b7b2e4366dd4a6a5..ccf622999a5be8359865e20f5bb38f6c06a78cbc 100644 (file)
@@ -27,7 +27,6 @@
 ###############################################################################
        .type   itlb_miss,@function
 ENTRY(itlb_miss)
-       and     ~EPSW_NMID,epsw
 #ifdef CONFIG_GDBSTUB
        movm    [d2,d3,a2],(sp)
 #else
@@ -38,6 +37,12 @@ ENTRY(itlb_miss)
        nop
 #endif
 
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d2
+       mov     d2,(MMUCTR)
+#endif
+
+       and     ~EPSW_NMID,epsw
        mov     (IPTEU),d3
        mov     (PTBR),a2
        mov     d3,d2
@@ -79,7 +84,6 @@ itlb_miss_fault:
 ###############################################################################
        .type   dtlb_miss,@function
 ENTRY(dtlb_miss)
-       and     ~EPSW_NMID,epsw
 #ifdef CONFIG_GDBSTUB
        movm    [d2,d3,a2],(sp)
 #else
@@ -90,6 +94,12 @@ ENTRY(dtlb_miss)
        nop
 #endif
 
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d2
+       mov     d2,(MMUCTR)
+#endif
+
+       and     ~EPSW_NMID,epsw
        mov     (DPTEU),d3
        mov     (PTBR),a2
        mov     d3,d2
@@ -130,9 +140,15 @@ dtlb_miss_fault:
 ###############################################################################
        .type   itlb_aerror,@function
 ENTRY(itlb_aerror)
-       and     ~EPSW_NMID,epsw
        add     -4,sp
        SAVE_ALL
+
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d1
+       mov     d1,(MMUCTR)
+#endif
+
+       and     ~EPSW_NMID,epsw
        add     -4,sp                           # need to pass three params
 
        # calculate the fault code
@@ -148,7 +164,6 @@ ENTRY(itlb_aerror)
        clr     d0
        mov     d0,(IPTEL)
 
-       and     ~EPSW_NMID,epsw
        or      EPSW_IE,epsw
        mov     fp,d0
        call    do_page_fault[],0               # do_page_fault(regs,code,addr
@@ -163,10 +178,16 @@ ENTRY(itlb_aerror)
 ###############################################################################
        .type   dtlb_aerror,@function
 ENTRY(dtlb_aerror)
-       and     ~EPSW_NMID,epsw
        add     -4,sp
        SAVE_ALL
+
+#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
+       mov     (MMUCTR),d1
+       mov     d1,(MMUCTR)
+#endif
+
        add     -4,sp                           # need to pass three params
+       and     ~EPSW_NMID,epsw
 
        # calculate the fault code
        movhu   (MMUFCR_DFC),d1
@@ -180,7 +201,6 @@ ENTRY(dtlb_aerror)
        clr     d0
        mov     d0,(DPTEL)
 
-       and     ~EPSW_NMID,epsw
        or      EPSW_IE,epsw
        mov     fp,d0
        call    do_page_fault[],0               # do_page_fault(regs,code,addr