2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 2002, 2004, 2007 by Ralf Baechle
7 * Copyright (C) 2007 Maciej W. Rozycki
15 * Work around certain R4000 CPU errata (as implemented by GCC):
17 * - A double-word or a variable shift may give an incorrect result
18 * if executed immediately after starting an integer division:
19 * "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
21 * "MIPS R4000MC Errata, Processor Revision 2.2 and 3.0", erratum
24 * - A double-word or a variable shift may give an incorrect result
25 * if executed while an integer multiplication is in progress:
26 * "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
29 * - An integer division may give an incorrect result if started in
30 * a delay slot of a taken branch or a jump:
31 * "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
34 #ifdef CONFIG_CPU_R4000_WORKAROUNDS
41 * Work around certain R4400 CPU errata (as implemented by GCC):
43 * - A double-word or a variable shift may give an incorrect result
44 * if executed immediately after starting an integer division:
45 * "MIPS R4400MC Errata, Processor Revision 1.0", erratum #10
46 * "MIPS R4400MC Errata, Processor Revision 2.0 & 3.0", erratum #4
48 #ifdef CONFIG_CPU_R4400_WORKAROUNDS
55 * Work around the "daddi" and "daddiu" CPU errata:
57 * - The `daddi' instruction fails to trap on overflow.
58 * "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
61 * - The `daddiu' instruction can produce an incorrect result.
62 * "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
64 * "MIPS R4000MC Errata, Processor Revision 2.2 and 3.0", erratum
66 * "MIPS R4400PC/SC Errata, Processor Revision 1.0", erratum #7
67 * "MIPS R4400MC Errata, Processor Revision 1.0", erratum #5
69 #ifdef CONFIG_CPU_DADDI_WORKAROUNDS
76 * Writeback and invalidate the primary cache dcache before DMA.
78 * R4600 v2.0 bug: "The CACHE instructions Hit_Writeback_Inv_D,
79 * Hit_Writeback_D, Hit_Invalidate_D and Create_Dirty_Exclusive_D will only
80 * operate correctly if the internal data cache refill buffer is empty. These
81 * CACHE instructions should be separated from any potential data cache miss
82 * by a load instruction to an uncached address to empty the response buffer."
83 * (Revision 2.0 device errata from IDT available on https://www.idt.com/
86 #ifndef R4600_V2_HIT_CACHEOP_WAR
87 #error Check setting of R4600_V2_HIT_CACHEOP_WAR for your platform
91 * Workaround for the Sibyte M3 errata the text of which can be found at
93 * http://sibyte.broadcom.com/hw/bcm1250/docs/pass2errata.txt
95 * This will enable the use of a special TLB refill handler which does a
96 * consistency check on the information in c0_badvaddr and c0_entryhi and
97 * will just return and take the exception again if the information was
98 * found to be inconsistent.
100 #ifndef BCM1250_M3_WAR
101 #error Check setting of BCM1250_M3_WAR for your platform
105 * This is a DUART workaround related to glitches around register accesses
107 #ifndef SIBYTE_1956_WAR
108 #error Check setting of SIBYTE_1956_WAR for your platform
112 * Fill buffers not flushed on CACHE instructions
114 * Hit_Invalidate_I cacheops invalidate an icache line but the refill
115 * for that line can get stale data from the fill buffer instead of
116 * accessing memory if the previous icache miss was also to that line.
118 * Workaround: generate an icache refill from a different line
121 * MIPS 4K RTL revision <3.0, PRID revision <4
123 #ifndef MIPS4K_ICACHE_REFILL_WAR
124 #error Check setting of MIPS4K_ICACHE_REFILL_WAR for your platform
128 * Missing implicit forced flush of evictions caused by CACHE
131 * Evictions caused by a CACHE instructions are not forced on to the
132 * bus. The BIU gives higher priority to fetches than to the data from
133 * the eviction buffer and no collision detection is performed between
134 * fetches and pending data from the eviction buffer.
136 * Workaround: Execute a SYNC instruction after the cache instruction
139 * MIPS 5Kc,5Kf RTL revision <2.3, PRID revision <8
140 * MIPS 20Kc RTL revision <4.0, PRID revision <?
142 #ifndef MIPS_CACHE_SYNC_WAR
143 #error Check setting of MIPS_CACHE_SYNC_WAR for your platform
147 * From TX49/H2 manual: "If the instruction (i.e. CACHE) is issued for
148 * the line which this instruction itself exists, the following
149 * operation is not guaranteed."
151 * Workaround: do two phase flushing for Index_Invalidate_I
153 #ifndef TX49XX_ICACHE_INDEX_INV_WAR
154 #error Check setting of TX49XX_ICACHE_INDEX_INV_WAR for your platform
158 * The RM7000 processors and the E9000 cores have a bug (though PMC-Sierra
159 * opposes it being called that) where invalid instructions in the same
160 * I-cache line worth of instructions being fetched may case spurious
163 #ifndef ICACHE_REFILLS_WORKAROUND_WAR
164 #error Check setting of ICACHE_REFILLS_WORKAROUND_WAR for your platform
168 * On the R10000 up to version 2.6 (not sure about 2.7) there is a bug that
169 * may cause ll / sc and lld / scd sequences to execute non-atomically.
171 #ifndef R10000_LLSC_WAR
172 #error Check setting of R10000_LLSC_WAR for your platform
176 * 34K core erratum: "Problems Executing the TLBR Instruction"
178 #ifndef MIPS34K_MISSED_ITLB_WAR
179 #error Check setting of MIPS34K_MISSED_ITLB_WAR for your platform
182 #endif /* _ASM_WAR_H */