From dbdf20db537a5369c65330f878ad4905020a8bfa Mon Sep 17 00:00:00 2001 From: Bernd Schmidt Date: Wed, 7 Jan 2009 23:14:38 +0800 Subject: Blackfin arch: Faster C implementation of no-MPU CPLB handler This is a mixture ofcMichael McTernan's patch and the existing cplb-mpu code. We ditch the old cplb-nompu implementation, which is a good example of why a good algorithm in a HLL is preferrable to a bad algorithm written in assembly. Rather than try to construct a table of all posible CPLBs and search it, we just create a (smaller) table of memory regions and their attributes. Some of the data structures are now unified for both the mpu and nompu cases. A lot of needless complexity in cplbinit.c is removed. Further optimizations: * compile cplbmgr.c with a lot of -ffixed-reg options, and omit saving these registers on the stack when entering a CPLB exception. * lose cli/nop/nop/sti sequences for some workarounds - these don't * make sense in an exception context Additional code unification should be possible after this. [Mike Frysinger : - convert CPP if statements to C if statements - remove redundant statements - use a do...while loop rather than a for loop to get slightly better optimization and to avoid gcc "may be used uninitialized" warnings ... we know that the [id]cplb_nr_bounds variables will never be 0, so this is OK - the no-mpu code was the last user of MAX_MEM_SIZE and with that rewritten, we can punt it - add some BUG_ON() checks to make sure we dont overflow the small cplb_bounds array - add i/d cplb entries for the bootrom because there is functions/data in there we want to access - we do not need a NULL trailing entry as any time we access the bounds arrays, we use the nr_bounds variable ] Signed-off-by: Michael McTernan Signed-off-by: Mike Frysinger Signed-off-by: Bernd Schmidt Signed-off-by: Bryan Wu --- arch/blackfin/kernel/cplb-nompu/cplbhdlr.S | 130 ----------------------------- 1 file changed, 130 deletions(-) delete mode 100644 arch/blackfin/kernel/cplb-nompu/cplbhdlr.S (limited to 'arch/blackfin/kernel/cplb-nompu/cplbhdlr.S') diff --git a/arch/blackfin/kernel/cplb-nompu/cplbhdlr.S b/arch/blackfin/kernel/cplb-nompu/cplbhdlr.S deleted file mode 100644 index ecbabc0a1fed..000000000000 --- a/arch/blackfin/kernel/cplb-nompu/cplbhdlr.S +++ /dev/null @@ -1,130 +0,0 @@ -/* - * File: arch/blackfin/mach-common/cplbhdlr.S - * Based on: - * Author: LG Soft India - * - * Created: ? - * Description: CPLB exception handler - * - * Modified: - * Copyright 2004-2006 Analog Devices Inc. - * - * Bugs: Enter bugs at http://blackfin.uclinux.org/ - * - * 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, see the file COPYING, or write - * to the Free Software Foundation, Inc., - * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include -#include -#include - -#ifdef CONFIG_EXCPT_IRQ_SYSC_L1 -.section .l1.text -#else -.text -#endif - -.type _cplb_mgr, STT_FUNC; -.type _panic_cplb_error, STT_FUNC; - -.align 2 - -ENTRY(__cplb_hdr) - R2 = SEQSTAT; - - /* Mask the contents of SEQSTAT and leave only EXCAUSE in R2 */ - R2 <<= 26; - R2 >>= 26; - - R1 = 0x23; /* Data access CPLB protection violation */ - CC = R2 == R1; - IF !CC JUMP .Lnot_data_write; - R0 = 2; /* is a write to data space*/ - JUMP .Lis_icplb_miss; - -.Lnot_data_write: - R1 = 0x2C; /* CPLB miss on an instruction fetch */ - CC = R2 == R1; - R0 = 0; /* is_data_miss == False*/ - IF CC JUMP .Lis_icplb_miss; - - R1 = 0x26; - CC = R2 == R1; - IF !CC JUMP .Lunknown; - - R0 = 1; /* is_data_miss == True*/ - -.Lis_icplb_miss: - -#if defined(CONFIG_BFIN_ICACHE) || defined(CONFIG_BFIN_DCACHE) -# if defined(CONFIG_BFIN_ICACHE) && !defined(CONFIG_BFIN_DCACHE) - R1 = CPLB_ENABLE_ICACHE; -# endif -# if !defined(CONFIG_BFIN_ICACHE) && defined(CONFIG_BFIN_DCACHE) - R1 = CPLB_ENABLE_DCACHE; -# endif -# if defined(CONFIG_BFIN_ICACHE) && defined(CONFIG_BFIN_DCACHE) - R1 = CPLB_ENABLE_DCACHE | CPLB_ENABLE_ICACHE; -# endif -#else - R1 = 0; -#endif - - [--SP] = RETS; - CALL _cplb_mgr; - RETS = [SP++]; - CC = R0 == 0; - IF !CC JUMP .Lnot_replaced; - RTS; - -/* - * Diagnostic exception handlers - */ -.Lunknown: - R0 = CPLB_UNKNOWN_ERR; - JUMP .Lcplb_error; - -.Lnot_replaced: - CC = R0 == CPLB_NO_UNLOCKED; - IF !CC JUMP .Lnext_check; - R0 = CPLB_NO_UNLOCKED; - JUMP .Lcplb_error; - -.Lnext_check: - CC = R0 == CPLB_NO_ADDR_MATCH; - IF !CC JUMP .Lnext_check2; - R0 = CPLB_NO_ADDR_MATCH; - JUMP .Lcplb_error; - -.Lnext_check2: - CC = R0 == CPLB_PROT_VIOL; - IF !CC JUMP .Lstrange_return_from_cplb_mgr; - R0 = CPLB_PROT_VIOL; - JUMP .Lcplb_error; - -.Lstrange_return_from_cplb_mgr: - IDLE; - CSYNC; - JUMP .Lstrange_return_from_cplb_mgr; - -.Lcplb_error: - R1 = sp; - SP += -12; - call _panic_cplb_error; - SP += 12; - JUMP.L _handle_bad_cplb; - -ENDPROC(__cplb_hdr) -- cgit v1.2.3-59-g8ed1b