Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754312Ab0HBTYM (ORCPT ); Mon, 2 Aug 2010 15:24:12 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:32858 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753747Ab0HBTYL (ORCPT ); Mon, 2 Aug 2010 15:24:11 -0400 Message-ID: <4C571B25.3080806@kernel.org> Date: Mon, 02 Aug 2010 12:23:17 -0700 From: Yinghai Lu User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.11) Gecko/20100714 SUSE/3.0.6 Thunderbird/3.0.6 MIME-Version: 1.0 To: Cyrill Gorcunov CC: "H. Peter Anvin" , Ingo Molnar , Thomas Gleixner , Pekka Enberg , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/2] x86, setup: reorgize the early_console_setup References: <4C56701B.1030000@kernel.org> <20100802150958.GA5544@lenovo> In-Reply-To: <20100802150958.GA5544@lenovo> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsmt353.oracle.com [141.146.40.153] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090205.4C571B2A.02B2,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6052 Lines: 179 On 08/02/2010 08:09 AM, Cyrill Gorcunov wrote: > On Mon, Aug 02, 2010 at 12:13:31AM -0700, Yinghai Lu wrote: >> >> Seperate early_console_setup from tty.c >> also make main.c to include printf.c/string.c/cmdline.c >> >> will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c >> >> Signed-off-by: Yinghai Lu >> >> --- > > Hi Yinghai, I'll try to find some time for review though it looks somehow > too 'big' for me :) > > Actually by reading your initial approach (which was much smaller in size) I > thought we end up in something like the patch below, though I'll review this > seris. So just to share (I've tested it under qemu). The idea is the same as > your was, so I pushed all constant parts into header and use it when needed > passing serial line base port via boot_params. Eric doesn't like early_serial_console_base in zero page. and said that is fragile. So try to include string.c/printf.c/cmdline.c/early_serial_console.c in arch/x86/boot/compressed/misc.c and analyze that command line again. then kexec path will get support too. that is from arch/x86/boot/compressed/head_32.S or head_64.S, startup_32. and skip arch/x86/boot/main.c later with following patch for 3, we get all covered in c code. 1. arch/x86/boot/main.c: setup code. 2. arch/x86/boot/compressed/misc.c: decompress_kernel code : the 2 -v3 patches that i sent last night. 3. arch/x86/kernel/head64.c: real kernel. maybe we can make early_serial_console.c and early_printk.c to share some .h etc later. Thanks Yinghai [PATCH -v2] x86: Setup early console as early as possible Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console. only can handle io port kind of 8250. because mmio need ioremap. -v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa update after using x86 memblock patchset Signed-off-by: Yinghai Lu --- arch/x86/include/asm/setup.h | 2 ++ arch/x86/kernel/head.c | 27 +++++++++++++++++++++++++++ arch/x86/kernel/head32.c | 2 ++ arch/x86/kernel/head64.c | 13 +++++++++++-- kernel/printk.c | 4 ++++ 5 files changed, 46 insertions(+), 2 deletions(-) Index: linux-2.6/arch/x86/include/asm/setup.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/setup.h +++ linux-2.6/arch/x86/include/asm/setup.h @@ -42,6 +42,8 @@ static inline void visws_early_detect(vo #endif extern unsigned long saved_video_mode; +int setup_early_serial8250_console(char *cmdline); +void setup_early_console(void); extern void reserve_standard_io_resources(void); extern void i386_reserve_resources(void); Index: linux-2.6/arch/x86/kernel/head.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/head.c +++ linux-2.6/arch/x86/kernel/head.c @@ -54,3 +54,30 @@ void __init reserve_ebda_region(void) /* reserve all memory between lowmem and the 1MB mark */ memblock_x86_reserve_range(lowmem, 0x100000, "* BIOS reserved"); } + + +void __init setup_early_console(void) +{ +#ifdef CONFIG_SERIAL_8250_CONSOLE + char constr[64], *p, *q; + + /* Can not handle mmio type 8250 uart yet, too early */ + p = strstr(boot_command_line, "console=uart8250,io,"); + if (!p) + p = strstr(boot_command_line, "console=uart,io,"); + if (!p) + return; + + p += 8; /* sizeof "console=" */ + q = strchr(p, ' '); + if ((q - p) >= sizeof(constr)) + return; + + memset(constr, 0, sizeof(constr)); + memcpy(constr, p, q - p); + + lockdep_init(); + + setup_early_serial8250_console(constr); +#endif +} Index: linux-2.6/arch/x86/kernel/head32.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/head32.c +++ linux-2.6/arch/x86/kernel/head32.c @@ -31,6 +31,8 @@ static void __init i386_default_early_se void __init i386_start_kernel(void) { + setup_early_console(); + memblock_init(); #ifdef CONFIG_X86_TRAMPOLINE Index: linux-2.6/arch/x86/kernel/head64.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/head64.c +++ linux-2.6/arch/x86/kernel/head64.c @@ -46,6 +46,10 @@ static void __init copy_bootdata(char *r { char * command_line; + /* make sure if it is copied already */ + if (boot_params.hdr.version) + return; + memcpy(&boot_params, real_mode_data, sizeof boot_params); if (boot_params.hdr.cmd_line_ptr) { command_line = __va(boot_params.hdr.cmd_line_ptr); @@ -74,6 +78,10 @@ void __init x86_64_start_kernel(char * r /* clear bss before set_intr_gate with early_idt_handler */ clear_bss(); + /* boot_params is in bss */ + copy_bootdata(__va(real_mode_data)); + setup_early_console(); + /* Make NULL pointers segfault */ zap_identity_mappings(); @@ -97,9 +105,10 @@ void __init x86_64_start_kernel(char * r void __init x86_64_start_reservations(char *real_mode_data) { - memblock_init(); - copy_bootdata(__va(real_mode_data)); + setup_early_console(); + + memblock_init(); memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS"); Index: linux-2.6/kernel/printk.c =================================================================== --- linux-2.6.orig/kernel/printk.c +++ linux-2.6/kernel/printk.c @@ -1204,6 +1204,10 @@ void register_console(struct console *ne if (console_drivers && newcon->flags & CON_BOOT) { /* find the last or real console */ for_each_console(bcon) { + /* not again */ + if (bcon == newcon) + return; + if (!(bcon->flags & CON_BOOT)) { printk(KERN_INFO "Too late to register bootconsole %s%d\n", newcon->name, newcon->index); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/