powerpc: Move l2cr.S over to arch/powerpc

No functional changes, but call it l2cr_6xx.S since it is specific
to 6xx-family (including G3/750 and G4/74xx) processors.

Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 472 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index f2c47e907037..e7fddf1e42c7 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -34,7 +34,7 @@ obj-$(CONFIG_IBMEBUS)           += ibmebus.o
 obj-$(CONFIG_GENERIC_TBSYNC)    += smp-tbsync.o
 obj64-$(CONFIG_PPC_MULTIPLATFORM) += nvram_64.o
 obj-$(CONFIG_CRASH_DUMP)        += crash_dump.o
-obj-$(CONFIG_6xx)               += idle_6xx.o
+obj-$(CONFIG_6xx)               += idle_6xx.o l2cr_6xx.o
 
 ifeq ($(CONFIG_PPC_MERGE),y)
 
diff --git a/arch/powerpc/kernel/l2cr_6xx.S b/arch/powerpc/kernel/l2cr_6xx.S
new file mode 100644
index 000000000000..d7f4e982b539
--- /dev/null
+++ b/arch/powerpc/kernel/l2cr_6xx.S
@@ -0,0 +1,471 @@
+/*
+        L2CR functions
+        Copyright © 1997-1998 by PowerLogix R & D, Inc.
+
+        This program is free software; you can redistribute it and/or modify
+        it under the terms of the GNU General Public License as published by
+        the Free Software Foundation; either version 2 of the License, or
+        (at your option) any later version.
+
+        This program is distributed in the hope that it will be useful,
+        but WITHOUT ANY WARRANTY; without even the implied warranty of
+        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+        GNU General Public License for more details.
+
+        You should have received a copy of the GNU General Public License
+        along with this program; if not, write to the Free Software
+        Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+/*
+        Thur, Dec. 12, 1998.
+        - First public release, contributed by PowerLogix.
+        ***********
+        Sat, Aug. 7, 1999.
+        - Terry: Made sure code disabled interrupts before running. (Previously
+                        it was assumed interrupts were already disabled).
+        - Terry: Updated for tentative G4 support.  4MB of memory is now flushed
+                        instead of 2MB.  (Prob. only 3 is necessary).
+        - Terry: Updated for workaround to HID0[DPM] processor bug
+                        during global invalidates.
+        ***********
+        Thu, July 13, 2000.
+        - Terry: Added isync to correct for an errata.
+
+        22 August 2001.
+        - DanM: Finally added the 7450 patch I've had for the past
+                several months.  The L2CR is similar, but I'm going
+                to assume the user of this functions knows what they
+                are doing.
+
+        Author: Terry Greeniaus (tgree@phys.ualberta.ca)
+        Please e-mail updates to this file to me, thanks!
+*/
+#include <linux/config.h>
+#include <asm/processor.h>
+#include <asm/cputable.h>
+#include <asm/ppc_asm.h>
+#include <asm/cache.h>
+#include <asm/page.h>
+
+/* Usage:
+
+        When setting the L2CR register, you must do a few special
+        things.  If you are enabling the cache, you must perform a
+        global invalidate.  If you are disabling the cache, you must
+        flush the cache contents first.  This routine takes care of
+        doing these things.  When first enabling the cache, make sure
+        you pass in the L2CR you want, as well as passing in the
+        global invalidate bit set.  A global invalidate will only be
+        performed if the L2I bit is set in applyThis.  When enabling
+        the cache, you should also set the L2E bit in applyThis.  If
+        you want to modify the L2CR contents after the cache has been
+        enabled, the recommended procedure is to first call
+        __setL2CR(0) to disable the cache and then call it again with
+        the new values for L2CR.  Examples:
+
+        _setL2CR(0)             - disables the cache
+        _setL2CR(0xB3A04000)    - enables my G3 upgrade card:
+                                - L2E set to turn on the cache
+                                - L2SIZ set to 1MB
+                                - L2CLK set to 1:1
+                                - L2RAM set to pipelined synchronous late-write
+                                - L2I set to perform a global invalidation
+                                - L2OH set to 0.5 nS
+                                - L2DF set because this upgrade card
+                                  requires it
+
+        A similar call should work for your card.  You need to know
+        the correct setting for your card and then place them in the
+        fields I have outlined above.  Other fields support optional
+        features, such as L2DO which caches only data, or L2TS which
+        causes cache pushes from the L1 cache to go to the L2 cache
+        instead of to main memory.
+
+IMPORTANT:
+        Starting with the 7450, the bits in this register have moved
+        or behave differently.  The Enable, Parity Enable, Size,
+        and L2 Invalidate are the only bits that have not moved.
+        The size is read-only for these processors with internal L2
+        cache, and the invalidate is a control as well as status.
+                -- Dan
+
+*/
+/*
+ * Summary: this procedure ignores the L2I bit in the value passed in,
+ * flushes the cache if it was already enabled, always invalidates the
+ * cache, then enables the cache if the L2E bit is set in the value
+ * passed in.
+ *   -- paulus.
+ */
+_GLOBAL(_set_L2CR)
+        /* Make sure this is a 750 or 7400 chip */
+BEGIN_FTR_SECTION
+        li      r3,-1
+        blr
+END_FTR_SECTION_IFCLR(CPU_FTR_L2CR)
+
+        mflr    r9
+
+        /* Stop DST streams */
+BEGIN_FTR_SECTION
+        DSSALL
+        sync
+END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
+
+        /* Turn off interrupts and data relocation. */
+        mfmsr   r7              /* Save MSR in r7 */
+        rlwinm  r4,r7,0,17,15
+        rlwinm  r4,r4,0,28,26   /* Turn off DR bit */
+        sync
+        mtmsr   r4
+        isync
+
+        /* Before we perform the global invalidation, we must disable dynamic
+         * power management via HID0[DPM] to work around a processor bug where
+         * DPM can possibly interfere with the state machine in the processor
+         * that invalidates the L2 cache tags.
+         */
+        mfspr   r8,SPRN_HID0            /* Save HID0 in r8 */
+        rlwinm  r4,r8,0,12,10           /* Turn off HID0[DPM] */
+        sync
+        mtspr   SPRN_HID0,r4            /* Disable DPM */
+        sync
+
+        /* Get the current enable bit of the L2CR into r4 */
+        mfspr   r4,SPRN_L2CR
+
+        /* Tweak some bits */
+        rlwinm  r5,r3,0,0,0             /* r5 contains the new enable bit */
+        rlwinm  r3,r3,0,11,9            /* Turn off the invalidate bit */
+        rlwinm  r3,r3,0,1,31            /* Turn off the enable bit */
+
+        /* Check to see if we need to flush */
+        rlwinm. r4,r4,0,0,0
+        beq     2f
+
+        /* Flush the cache. First, read the first 4MB of memory (physical) to
+         * put new data in the cache.  (Actually we only need
+         * the size of the L2 cache plus the size of the L1 cache, but 4MB will
+         * cover everything just to be safe).
+         */
+
+         /**** Might be a good idea to set L2DO here - to prevent instructions
+               from getting into the cache.  But since we invalidate
+               the next time we enable the cache it doesn't really matter.
+               Don't do this unless you accomodate all processor variations.
+               The bit moved on the 7450.....
+          ****/
+
+BEGIN_FTR_SECTION
+        /* Disable L2 prefetch on some 745x and try to ensure
+         * L2 prefetch engines are idle. As explained by errata
+         * text, we can't be sure they are, we just hope very hard
+         * that well be enough (sic !). At least I noticed Apple
+         * doesn't even bother doing the dcbf's here...
+         */
+        mfspr   r4,SPRN_MSSCR0
+        rlwinm  r4,r4,0,0,29
+        sync
+        mtspr   SPRN_MSSCR0,r4
+        sync
+        isync
+        lis     r4,KERNELBASE@h
+        dcbf    0,r4
+        dcbf    0,r4
+        dcbf    0,r4
+        dcbf    0,r4
+END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450)
+
+        /* TODO: use HW flush assist when available */
+
+        lis     r4,0x0002
+        mtctr   r4
+        li      r4,0
+1:
+        lwzx    r0,r0,r4
+        addi    r4,r4,32                /* Go to start of next cache line */
+        bdnz    1b
+        isync
+
+        /* Now, flush the first 4MB of memory */
+        lis     r4,0x0002
+        mtctr   r4
+        li      r4,0
+        sync
+1:
+        dcbf    0,r4
+        addi    r4,r4,32                /* Go to start of next cache line */
+        bdnz    1b
+
+2:
+        /* Set up the L2CR configuration bits (and switch L2 off) */
+        /* CPU errata: Make sure the mtspr below is already in the
+         * L1 icache
+         */
+        b       20f
+        .balign L1_CACHE_BYTES
+22:
+        sync
+        mtspr   SPRN_L2CR,r3
+        sync
+        b       23f
+20:
+        b       21f
+21:     sync
+        isync
+        b       22b
+
+23:
+        /* Perform a global invalidation */
+        oris    r3,r3,0x0020
+        sync
+        mtspr   SPRN_L2CR,r3
+        sync
+        isync                           /* For errata */
+
+BEGIN_FTR_SECTION
+        /* On the 7450, we wait for the L2I bit to clear......
+        */
+10:     mfspr   r3,SPRN_L2CR
+        andis.  r4,r3,0x0020
+        bne     10b
+        b       11f
+END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450)
+
+        /* Wait for the invalidation to complete */
+3:      mfspr   r3,SPRN_L2CR
+        rlwinm. r4,r3,0,31,31
+        bne     3b
+
+11:     rlwinm  r3,r3,0,11,9            /* Turn off the L2I bit */
+        sync
+        mtspr   SPRN_L2CR,r3
+        sync
+
+        /* See if we need to enable the cache */
+        cmplwi  r5,0
+        beq     4f
+
+        /* Enable the cache */
+        oris    r3,r3,0x8000
+        mtspr   SPRN_L2CR,r3
+        sync
+        
+        /* Enable L2 HW prefetch on 744x/745x */
+BEGIN_FTR_SECTION
+        mfspr   r3,SPRN_MSSCR0
+        ori     r3,r3,3
+        sync
+        mtspr   SPRN_MSSCR0,r3
+        sync
+        isync
+END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450)
+4:
+
+        /* Restore HID0[DPM] to whatever it was before */
+        sync
+        mtspr   1008,r8
+        sync
+
+        /* Restore MSR (restores EE and DR bits to original state) */
+        SYNC
+        mtmsr   r7
+        isync
+
+        mtlr    r9
+        blr
+
+_GLOBAL(_get_L2CR)
+        /* Return the L2CR contents */
+        li      r3,0
+BEGIN_FTR_SECTION
+        mfspr   r3,SPRN_L2CR
+END_FTR_SECTION_IFSET(CPU_FTR_L2CR)
+        blr
+
+
+/*
+ * Here is a similar routine for dealing with the L3 cache
+ * on the 745x family of chips
+ */
+
+_GLOBAL(_set_L3CR)
+        /* Make sure this is a 745x chip */
+BEGIN_FTR_SECTION
+        li      r3,-1
+        blr
+END_FTR_SECTION_IFCLR(CPU_FTR_L3CR)
+
+        /* Turn off interrupts and data relocation. */
+        mfmsr   r7              /* Save MSR in r7 */
+        rlwinm  r4,r7,0,17,15
+        rlwinm  r4,r4,0,28,26   /* Turn off DR bit */
+        sync
+        mtmsr   r4
+        isync
+
+        /* Stop DST streams */
+        DSSALL
+        sync
+
+        /* Get the current enable bit of the L3CR into r4 */
+        mfspr   r4,SPRN_L3CR
+
+        /* Tweak some bits */
+        rlwinm  r5,r3,0,0,0             /* r5 contains the new enable bit */
+        rlwinm  r3,r3,0,22,20           /* Turn off the invalidate bit */
+        rlwinm  r3,r3,0,2,31            /* Turn off the enable & PE bits */
+        rlwinm  r3,r3,0,5,3             /* Turn off the clken bit */
+        /* Check to see if we need to flush */
+        rlwinm. r4,r4,0,0,0
+        beq     2f
+
+        /* Flush the cache.
+         */
+
+        /* TODO: use HW flush assist */
+
+        lis     r4,0x0008
+        mtctr   r4
+        li      r4,0
+1:
+        lwzx    r0,r0,r4
+        dcbf    0,r4
+        addi    r4,r4,32                /* Go to start of next cache line */
+        bdnz    1b
+
+2:
+        /* Set up the L3CR configuration bits (and switch L3 off) */
+        sync
+        mtspr   SPRN_L3CR,r3
+        sync
+
+        oris    r3,r3,L3CR_L3RES@h              /* Set reserved bit 5 */
+        mtspr   SPRN_L3CR,r3
+        sync
+        oris    r3,r3,L3CR_L3CLKEN@h            /* Set clken */
+        mtspr   SPRN_L3CR,r3
+        sync
+
+        /* Wait for stabilize */
+        li      r0,256
+        mtctr   r0
+1:      bdnz    1b
+
+        /* Perform a global invalidation */
+        ori     r3,r3,0x0400
+        sync
+        mtspr   SPRN_L3CR,r3
+        sync
+        isync
+
+        /* We wait for the L3I bit to clear...... */
+10:     mfspr   r3,SPRN_L3CR
+        andi.   r4,r3,0x0400
+        bne     10b
+
+        /* Clear CLKEN */
+        rlwinm  r3,r3,0,5,3             /* Turn off the clken bit */
+        mtspr   SPRN_L3CR,r3
+        sync
+
+        /* Wait for stabilize */
+        li      r0,256
+        mtctr   r0
+1:      bdnz    1b
+
+        /* See if we need to enable the cache */
+        cmplwi  r5,0
+        beq     4f
+
+        /* Enable the cache */
+        oris    r3,r3,(L3CR_L3E | L3CR_L3CLKEN)@h
+        mtspr   SPRN_L3CR,r3
+        sync
+
+        /* Wait for stabilize */
+        li      r0,256
+        mtctr   r0
+1:      bdnz    1b
+
+        /* Restore MSR (restores EE and DR bits to original state) */
+4:      SYNC
+        mtmsr   r7
+        isync
+        blr
+
+_GLOBAL(_get_L3CR)
+        /* Return the L3CR contents */
+        li      r3,0
+BEGIN_FTR_SECTION
+        mfspr   r3,SPRN_L3CR
+END_FTR_SECTION_IFSET(CPU_FTR_L3CR)
+        blr
+
+/* --- End of PowerLogix code ---
+ */
+
+
+/* flush_disable_L1()   - Flush and disable L1 cache
+ *
+ * clobbers r0, r3, ctr, cr0
+ * Must be called with interrupts disabled and MMU enabled.
+ */
+_GLOBAL(__flush_disable_L1)
+        /* Stop pending alitvec streams and memory accesses */
+BEGIN_FTR_SECTION
+        DSSALL
+END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
+        sync
+
+        /* Load counter to 0x4000 cache lines (512k) and
+         * load cache with datas
+         */
+        li      r3,0x4000       /* 512kB / 32B */
+        mtctr   r3
+        lis     r3,KERNELBASE@h
+1:
+        lwz     r0,0(r3)
+        addi    r3,r3,0x0020    /* Go to start of next cache line */
+        bdnz    1b
+        isync
+        sync
+
+        /* Now flush those cache lines */
+        li      r3,0x4000       /* 512kB / 32B */
+        mtctr   r3
+        lis     r3,KERNELBASE@h
+1:
+        dcbf    0,r3
+        addi    r3,r3,0x0020    /* Go to start of next cache line */
+        bdnz    1b
+        sync
+
+        /* We can now disable the L1 cache (HID0:DCE, HID0:ICE) */
+        mfspr   r3,SPRN_HID0
+        rlwinm  r3,r3,0,18,15
+        mtspr   SPRN_HID0,r3
+        sync
+        isync
+        blr
+
+/* inval_enable_L1      - Invalidate and enable L1 cache
+ *
+ * Assumes L1 is already disabled and MSR:EE is off
+ *
+ * clobbers r3
+ */
+_GLOBAL(__inval_enable_L1)
+        /* Enable and then Flash inval the instruction & data cache */
+        mfspr   r3,SPRN_HID0
+        ori     r3,r3, HID0_ICE|HID0_ICFI|HID0_DCE|HID0_DCI
+        sync
+        isync
+        mtspr   SPRN_HID0,r3
+        xori    r3,r3, HID0_ICFI|HID0_DCI
+        mtspr   SPRN_HID0,r3
+        sync
+
+        blr
+
+