From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 161E0C433EF for ; Sun, 15 May 2022 12:42:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232084AbiEOMmf (ORCPT ); Sun, 15 May 2022 08:42:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236680AbiEOMmR (ORCPT ); Sun, 15 May 2022 08:42:17 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44F89120B9 for ; Sun, 15 May 2022 05:42:15 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id ds11so392355pjb.0 for ; Sun, 15 May 2022 05:42:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=xo5Ghd/3yJ7FLKh8D+m75D1eKalJcyY8jdsgr84yU/I=; b=UGg9D7WDFM+99mE8iFDNjNTGmvsUchZrGHxjkNG2X2WjeW5oP6TQ5UaSLuw1EjGEwB 80Qrsfzq9EPBq+vMCE9MYV22lKl3bQrI+Gzhp4HfsRRoEsCWsyj2buZfsgHIR3Xf604B 6BBckUO6kB2Xp3GyL5BScTftLwfgXZnZ47e9rxBqjXpAJKnPwnVlozwGpYtdHhVBG8yA ljInbiCjp6/0O58ExEx/G/x9wOoxyP52cWeh2xSG9+Bxz1Ap1IxoTjBC1+5q1AVRe3gn l3rMTC3o+0SyuQn16w/26OXtpI1bZOftql5KG/gkZq7R+fUxUDnLtctPFH40HZ1ACTup 83Cg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=xo5Ghd/3yJ7FLKh8D+m75D1eKalJcyY8jdsgr84yU/I=; b=uobNhFEAv3ZqIgNc7oYAii2XMkAuL3/YsbNEfLHGeKQX1n81uqvULZmdal4lWEuZ92 cYgviQf021nS1Hq5itloymV36UjT+adocGa3LereGmqTBBVkkDRhesSDIZWI/bErVClT iuPa2KZ9OEX5ympXdyxHTf5mYsrq6247GML8a7TYRZ2HJQUCTqVEElClXH4LziPKZkIG uzNpYCRaBNxNFUJecUGcN2dZpE0bQ4/WOvG84vBNJPkVlEDcAzpjHgKVvVpX8THvbUdD p/u/QkFZakwq2TApKNYjTSQvVNzVgjqKDbi6iDdndTTB1J2mq62TvnrcNrHiIBQ/tKh0 48vg== X-Gm-Message-State: AOAM533Q2CrIaESG1kk1mr0oY9ObXqoTFYBWm3euR2bvfNt3l8T0twOv 9AbH10sdaJ/qhYQZQwUUt0v0fCckrZfpkg== X-Google-Smtp-Source: ABdhPJyk6e85mbLA1N9B5xixcrQxE0nu+AzMGR3tpBKDUBP72f9SXKWY5HCUM6aRWIS6w0LDcXTlWA== X-Received: by 2002:a17:90a:7f94:b0:1cb:1853:da1b with SMTP id m20-20020a17090a7f9400b001cb1853da1bmr14161696pjl.14.1652618534246; Sun, 15 May 2022 05:42:14 -0700 (PDT) Received: from localhost ([2409:10:24a0:4700:e8ad:216a:2a9d:6d0c]) by smtp.gmail.com with ESMTPSA id g6-20020a17090ae58600b001cd4989febcsm6669885pjz.8.2022.05.15.05.42.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 15 May 2022 05:42:13 -0700 (PDT) From: Stafford Horne To: LKML Cc: Openrisc , Stafford Horne , Jonas Bonn , Stefan Kristiansson , Randy Dunlap Subject: [PATCH 02/13] openrisc: Cleanup emergency print handling Date: Sun, 15 May 2022 21:41:47 +0900 Message-Id: <20220515124158.3167452-3-shorne@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220515124158.3167452-1-shorne@gmail.com> References: <20220515124158.3167452-1-shorne@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The emergency print support only works for 8250 compatible serial ports. Now that OpenRISC platforms may be configured with different serial port hardware we don't want emergency print to try to print to non-existent hardware which will cause lockups. This patch contains several fixes to get emergency print working again: - Update symbol loading to not assume the location of symbols - Split the putc print operation out to its own function to allow for different future implementations. - Update _emergency_print_nr and _emergency_print to use the putc function. - Guard serial 8250 specific sequences by CONFIG_SERIAL_8250 - Update string line feed from lf,cr to cr,lf. Signed-off-by: Stafford Horne --- arch/openrisc/kernel/head.S | 148 +++++++++++++++++++++--------------- 1 file changed, 85 insertions(+), 63 deletions(-) diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S index 15f1b38dfe03..b1f3a65c271c 100644 --- a/arch/openrisc/kernel/head.S +++ b/arch/openrisc/kernel/head.S @@ -297,19 +297,23 @@ /* temporary store r3, r9 into r1, r10 */ ;\ l.addi r1,r3,0x0 ;\ l.addi r10,r9,0x0 ;\ - /* the string referenced by r3 must be low enough */ ;\ + LOAD_SYMBOL_2_GPR(r9,_string_unhandled_exception) ;\ + tophys (r3,r9) ;\ l.jal _emergency_print ;\ - l.ori r3,r0,lo(_string_unhandled_exception) ;\ + l.nop ;\ l.mfspr r3,r0,SPR_NPC ;\ l.jal _emergency_print_nr ;\ - l.andi r3,r3,0x1f00 ;\ - /* the string referenced by r3 must be low enough */ ;\ + l.andi r3,r3,0x1f00 ;\ + LOAD_SYMBOL_2_GPR(r9,_string_epc_prefix) ;\ + tophys (r3,r9) ;\ l.jal _emergency_print ;\ - l.ori r3,r0,lo(_string_epc_prefix) ;\ + l.nop ;\ l.jal _emergency_print_nr ;\ - l.mfspr r3,r0,SPR_EPCR_BASE ;\ + l.mfspr r3,r0,SPR_EPCR_BASE ;\ + LOAD_SYMBOL_2_GPR(r9,_string_nl) ;\ + tophys (r3,r9) ;\ l.jal _emergency_print ;\ - l.ori r3,r0,lo(_string_nl) ;\ + l.nop ;\ /* end of printing */ ;\ l.addi r3,r1,0x0 ;\ l.addi r9,r10,0x0 ;\ @@ -1530,65 +1534,99 @@ trampoline_out: l.jr r9 l.nop - /* - * DSCR: prints a string referenced by r3. + * DESC: Prints ASCII character stored in r7 * - * PRMS: r3 - address of the first character of null - * terminated string to be printed + * PRMS: r7 - a 32-bit value with an ASCII character in the first byte + * position. * - * PREQ: UART at UART_BASE_ADD has to be initialized + * PREQ: The UART at UART_BASE_ADD has to be initialized * - * POST: caller should be aware that r3, r9 are changed + * POST: internally used but restores: + * r4 - to store UART_BASE_ADD + * r5 - for loading OFF_TXFULL / THRE,TEMT + * r6 - for storing bitmask (SERIAL_8250) */ -ENTRY(_emergency_print) +ENTRY(_emergency_putc) EMERGENCY_PRINT_STORE_GPR4 EMERGENCY_PRINT_STORE_GPR5 EMERGENCY_PRINT_STORE_GPR6 - EMERGENCY_PRINT_STORE_GPR7 -2: - l.lbz r7,0(r3) - l.sfeq r7,r0 - l.bf 9f - l.nop -// putc: l.movhi r4,hi(UART_BASE_ADD) + l.ori r4,r4,lo(UART_BASE_ADD) +#elif defined(CONFIG_SERIAL_8250) + /* Check UART LSR THRE (hold) bit */ l.addi r6,r0,0x20 1: l.lbz r5,5(r4) l.andi r5,r5,0x20 l.sfeq r5,r6 l.bnf 1b - l.nop + l.nop + /* Write character */ l.sb 0(r4),r7 + /* Check UART LSR THRE|TEMT (hold, empty) bits */ l.addi r6,r0,0x60 1: l.lbz r5,5(r4) l.andi r5,r5,0x60 l.sfeq r5,r6 l.bnf 1b - l.nop + l.nop +#endif + EMERGENCY_PRINT_LOAD_GPR6 + EMERGENCY_PRINT_LOAD_GPR5 + EMERGENCY_PRINT_LOAD_GPR4 + l.jr r9 + l.nop + +/* + * DSCR: prints a string referenced by r3. + * + * PRMS: r3 - address of the first character of null + * terminated string to be printed + * + * PREQ: UART at UART_BASE_ADD has to be initialized + * + * POST: caller should be aware that r3, r9 are changed + */ +ENTRY(_emergency_print) + EMERGENCY_PRINT_STORE_GPR7 + EMERGENCY_PRINT_STORE_GPR9 + + /* Load character to r7, check for null terminator */ +2: l.lbz r7,0(r3) + l.sfeqi r7,0x0 + l.bf 9f + l.nop + + l.jal _emergency_putc + l.nop /* next character */ l.j 2b - l.addi r3,r3,0x1 + l.addi r3,r3,0x1 9: + EMERGENCY_PRINT_LOAD_GPR9 EMERGENCY_PRINT_LOAD_GPR7 - EMERGENCY_PRINT_LOAD_GPR6 - EMERGENCY_PRINT_LOAD_GPR5 - EMERGENCY_PRINT_LOAD_GPR4 l.jr r9 - l.nop + l.nop +/* + * DSCR: prints a number in r3 in hex. + * + * PRMS: r3 - a 32-bit unsigned integer + * + * PREQ: UART at UART_BASE_ADD has to be initialized + * + * POST: caller should be aware that r3, r9 are changed + */ ENTRY(_emergency_print_nr) - EMERGENCY_PRINT_STORE_GPR4 - EMERGENCY_PRINT_STORE_GPR5 - EMERGENCY_PRINT_STORE_GPR6 EMERGENCY_PRINT_STORE_GPR7 EMERGENCY_PRINT_STORE_GPR8 + EMERGENCY_PRINT_STORE_GPR9 l.addi r8,r0,32 // shift register @@ -1600,58 +1638,39 @@ ENTRY(_emergency_print_nr) /* don't skip the last zero if number == 0x0 */ l.sfeqi r8,0x4 l.bf 2f - l.nop + l.nop l.sfeq r7,r0 l.bf 1b - l.nop + l.nop 2: l.srl r7,r3,r8 l.andi r7,r7,0xf l.sflts r8,r0 - l.bf 9f + l.bf 9f + /* Numbers greater than 9 translate to a-f */ l.sfgtui r7,0x9 l.bnf 8f - l.nop + l.nop l.addi r7,r7,0x27 -8: - l.addi r7,r7,0x30 -// putc: - l.movhi r4,hi(UART_BASE_ADD) - - l.addi r6,r0,0x20 -1: l.lbz r5,5(r4) - l.andi r5,r5,0x20 - l.sfeq r5,r6 - l.bnf 1b - l.nop - - l.sb 0(r4),r7 - - l.addi r6,r0,0x60 -1: l.lbz r5,5(r4) - l.andi r5,r5,0x60 - l.sfeq r5,r6 - l.bnf 1b - l.nop + /* Convert to ascii and output character */ +8: l.jal _emergency_putc + l.addi r7,r7,0x30 /* next character */ l.j 2b l.addi r8,r8,-0x4 9: + EMERGENCY_PRINT_LOAD_GPR9 EMERGENCY_PRINT_LOAD_GPR8 EMERGENCY_PRINT_LOAD_GPR7 - EMERGENCY_PRINT_LOAD_GPR6 - EMERGENCY_PRINT_LOAD_GPR5 - EMERGENCY_PRINT_LOAD_GPR4 l.jr r9 - l.nop - + l.nop /* * This should be used for debugging only. @@ -1676,7 +1695,9 @@ ENTRY(_emergency_print_nr) ENTRY(_early_uart_init) l.movhi r3,hi(UART_BASE_ADD) + l.ori r3,r3,lo(UART_BASE_ADD) +#if defined(CONFIG_SERIAL_8250) l.addi r4,r0,0x7 l.sb 0x2(r3),r4 @@ -1694,9 +1715,10 @@ ENTRY(_early_uart_init) l.addi r4,r0,((UART_DIVISOR) & 0x000000ff) l.sb UART_DLL(r3),r4 l.sb 0x3(r3),r5 +#endif l.jr r9 - l.nop + l.nop .align 0x1000 .global _secondary_evbar @@ -1711,13 +1733,13 @@ _secondary_evbar: .section .rodata _string_unhandled_exception: - .string "\n\rRunarunaround: Unhandled exception 0x\0" + .string "\r\nRunarunaround: Unhandled exception 0x\0" _string_epc_prefix: .string ": EPC=0x\0" _string_nl: - .string "\n\r\0" + .string "\r\n\0" /* ========================================[ page aligned structures ]=== */ -- 2.31.1