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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E80C0C43215 for ; Fri, 15 Nov 2019 15:31:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7CDA2073A for ; Fri, 15 Nov 2019 15:31:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727627AbfKOPbH (ORCPT ); Fri, 15 Nov 2019 10:31:07 -0500 Received: from mga03.intel.com ([134.134.136.65]:22089 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727443AbfKOPbH (ORCPT ); Fri, 15 Nov 2019 10:31:07 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Nov 2019 07:31:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.68,308,1569308400"; d="scan'208";a="203609015" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga007.fm.intel.com with ESMTP; 15 Nov 2019 07:31:04 -0800 Received: by black.fi.intel.com (Postfix, from userid 1003) id 70EDDEB; Fri, 15 Nov 2019 17:31:03 +0200 (EET) From: Andy Shevchenko To: linux-efi@vger.kernel.org, mika.westerberg@linux.intel.com Cc: Andy Shevchenko , Ard Biesheuvel , Alexander Graf , Matt Fleming Subject: [PATCH v3] efi/earlycon: Remap entire framebuffer after page initialization Date: Fri, 15 Nov 2019 17:31:02 +0200 Message-Id: <20191115153102.51921-1-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org When the commit 69c1f396f25b ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") moved x86 specific EFI earlyprintk implementation to shared location it also tweaked the behaviour. In particular it dropped a trick with full framebuffer remapping after page initialization. This lead to two regressions: 1) very slow scrolling after page initialization; 2) kernel hang when keep_bootcon parameter is being provided. Returning the trick back fixes #2 and mitigates, i.e. reduces the window when slowness appears, #1 presumably due to eliminating heavy map()/unmap() operations per each pixel line on the screen. Fixes: 69c1f396f25b ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") Cc: Ard Biesheuvel Cc: Alexander Graf Cc: Matt Fleming Signed-off-by: Andy Shevchenko --- v3: - assign size in efi_earlycon_setup() - check base and size before mapping in early_efi_map_fb() drivers/firmware/efi/earlycon.c | 37 +++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/firmware/efi/earlycon.c b/drivers/firmware/efi/earlycon.c index c9a0efca17b0..60b5350c6105 100644 --- a/drivers/firmware/efi/earlycon.c +++ b/drivers/firmware/efi/earlycon.c @@ -16,15 +16,50 @@ static const struct font_desc *font; static u32 efi_x, efi_y; static u64 fb_base; +static u32 fb_size; static pgprot_t fb_prot; +static void *efi_fb; + +/* + * efi earlycon needs to use early_memremap() to map the framebuffer. + * But early_memremap() is not usable for 'earlycon=efifb keep_bootcon', + * memremap() should be used instead. memremap() will be available after + * paging_init() which is earlier than initcall callbacks. Thus adding this + * early initcall function early_efi_map_fb() to map the whole efi framebuffer. + */ +static int __init early_efi_map_fb(void) +{ + if (!fb_base || !fb_size) + return NULL; + + if (pgprot_val(fb_prot) == pgprot_val(PAGE_KERNEL)) + efi_fb = memremap(fb_base, fb_size, MEMREMAP_WB); + else + efi_fb = memremap(fb_base, fb_size, MEMREMAP_WC); + + return efi_fb ? 0 : -ENOMEM; +} +early_initcall(early_efi_map_fb); + +static void __exit early_efi_unmap_fb(void) +{ + memunmap(efi_fb); +} +__exitcall(early_efi_unmap_fb); static __ref void *efi_earlycon_map(unsigned long start, unsigned long len) { + if (efi_fb) + return efi_fb + start; + return early_memremap_prot(fb_base + start, len, pgprot_val(fb_prot)); } static __ref void efi_earlycon_unmap(void *addr, unsigned long len) { + if (efi_fb) + return; + early_memunmap(addr, len); } @@ -176,6 +211,8 @@ static int __init efi_earlycon_setup(struct earlycon_device *device, if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) fb_base |= (u64)screen_info.ext_lfb_base << 32; + fb_size = screen_info.lfb_size; + if (opt && !strcmp(opt, "ram")) fb_prot = PAGE_KERNEL; else -- 2.24.0