From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-la0-x230.google.com ([2a00:1450:4010:c03::230]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Uigdn-0001xp-Rv for barebox@lists.infradead.org; Sat, 01 Jun 2013 07:54:20 +0000 Received: by mail-la0-f48.google.com with SMTP id fs12so2058929lab.35 for ; Sat, 01 Jun 2013 00:53:57 -0700 (PDT) From: Antony Pavlov Date: Sat, 1 Jun 2013 11:52:45 +0400 Message-Id: <1370073169-29009-3-git-send-email-antonynpavlov@gmail.com> In-Reply-To: <1370073169-29009-1-git-send-email-antonynpavlov@gmail.com> References: <1370073169-29009-1-git-send-email-antonynpavlov@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 2/6] MIPS: pbl: add low-level debug asm macros for ns16550 To: barebox@lists.infradead.org This patch adds macros for ns16550 port initialisation and single char output. The macros can be used in MIPS asm pbl code. Signed-off-by: Antony Pavlov --- arch/mips/include/asm/debug_ll_ns16550.h | 100 ++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 arch/mips/include/asm/debug_ll_ns16550.h diff --git a/arch/mips/include/asm/debug_ll_ns16550.h b/arch/mips/include/asm/debug_ll_ns16550.h new file mode 100644 index 0000000..5dd1b39 --- /dev/null +++ b/arch/mips/include/asm/debug_ll_ns16550.h @@ -0,0 +1,100 @@ +/* + * Copyright (C) 2012, 2013 Antony Pavlov + * + * This file is part of barebox. + * See file CREDITS for list of people who contributed to this project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * 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. + * + */ + +/** @file + * This file contains declaration for early output support + */ +#ifndef __INCLUDE_MIPS_ASM_DEBUG_LL_NS16550_H__ +#define __INCLUDE_MIPS_ASM_DEBUG_LL_NS16550_H__ + +#ifdef CONFIG_DEBUG_LL + +#ifndef DEBUG_LL_UART_ADDR +#error DEBUG_LL_UART_ADDR is undefined! +#endif + +#ifndef DEBUG_LL_UART_SHIFT +#error DEBUG_LL_UART_SHIFT is undefined! +#endif + +#ifndef DEBUG_LL_UART_DIVISOR +#error DEBUG_LL_UART_DIVISOR is undefined! +#endif + +#endif /* CONFIG_DEBUG_LL */ + +#define UART_THR (0x0 << DEBUG_LL_UART_SHIFT) +#define UART_DLL (0x0 << DEBUG_LL_UART_SHIFT) +#define UART_DLM (0x1 << DEBUG_LL_UART_SHIFT) +#define UART_LCR (0x3 << DEBUG_LL_UART_SHIFT) +#define UART_LSR (0x5 << DEBUG_LL_UART_SHIFT) + +#define UART_LCR_W 0x07 /* Set UART to 8,N,2 & DLAB = 0 */ +#define UART_LCR_DLAB 0x87 /* Set UART to 8,N,2 & DLAB = 1 */ + +#define UART_LSR_THRE 0x20 /* Xmit holding register empty */ + +/* + * Macros for use in assembly language code + */ + +.macro debug_ll_ns16550_init +#ifdef CONFIG_DEBUG_LL + la t0, DEBUG_LL_UART_ADDR + + li t1, UART_LCR_DLAB /* DLAB on */ + sb t1, UART_LCR(t0) /* Write it out */ + + li t1, DEBUG_LL_UART_DIVISOR + sb t1, UART_DLL(t0) /* write low order byte */ + srl t1, t1, 8 + sb t1, UART_DLM(t0) /* write high order byte */ + + li t1, UART_LCR_W /* DLAB off */ + sb t1, UART_LCR(t0) /* Write it out */ +#endif /* CONFIG_DEBUG_LL */ +.endm + +/* + * output a character in a0 + */ +.macro debug_ll_ns16550_outc chr +#ifdef CONFIG_DEBUG_LL + li a0, \chr + la t0, DEBUG_LL_UART_ADDR + +1: lbu t1, UART_LSR(t0) /* get line status */ + nop + andi t1, t1, UART_LSR_THRE /* check for transmitter empty */ + beqz t1, 1b /* try again */ + nop + + sb a0, UART_THR(t0) /* write the character */ +#endif /* CONFIG_DEBUG_LL */ +.endm + +/* + * output CR + NL + */ +.macro debug_ll_ns16550_outnl +#ifdef CONFIG_DEBUG_LL + debug_ll_ns16550_outc '\r' + debug_ll_ns16550_outc '\n' +#endif /* CONFIG_DEBUG_LL */ +.endm + +#endif /* __INCLUDE_MIPS_ASM_DEBUG_LL_NS16550_H__ */ -- 1.7.10.4 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox