From df3443dfa449ad02bef8ddf6e2c90a6fd9394fc9 Mon Sep 17 00:00:00 2001 From: Bryan Wu Date: Tue, 24 Jun 2014 11:45:29 +0900 Subject: ARM: tegra: Disable VPR On Tegra114 and Tegra124 platforms, certain display-related registers cannot be accessed unless the VPR registers are programmed. For bootloader, we probably don't care about VPR, so we disable it (which counts as programming it, and allows those display-related registers to be accessed). This patch is based on the commit 5f499646c83ba08079f3fdff6591f638a0ce4c0c in Chromium OS U-Boot project. Signed-off-by: Andrew Chew Signed-off-by: Jimmy Zhang Signed-off-by: Bryan Wu [acourbot: ensure write went through, vpr.c style changes] Signed-off-by: Alexandre Courbot Reviewed-by: Stephen Warren Cc: Tom Warren Cc: Stephen Warren Cc: Terje Bergstrom Tested-by: Thierry Reding Signed-off-by: Tom Warren --- arch/arm/cpu/tegra-common/Makefile | 1 + arch/arm/cpu/tegra-common/ap.c | 3 +++ arch/arm/cpu/tegra-common/vpr.c | 35 +++++++++++++++++++++++++++++++++++ 3 files changed, 39 insertions(+) create mode 100644 arch/arm/cpu/tegra-common/vpr.c (limited to 'arch/arm/cpu/tegra-common') diff --git a/arch/arm/cpu/tegra-common/Makefile b/arch/arm/cpu/tegra-common/Makefile index 892556e644..a18c318739 100644 --- a/arch/arm/cpu/tegra-common/Makefile +++ b/arch/arm/cpu/tegra-common/Makefile @@ -14,3 +14,4 @@ obj-y += clock.o obj-y += lowlevel_init.o obj-y += pinmux-common.o obj-$(CONFIG_DISPLAY_CPUINFO) += sys_info.o +obj-$(CONFIG_TEGRA124) += vpr.o diff --git a/arch/arm/cpu/tegra-common/ap.c b/arch/arm/cpu/tegra-common/ap.c index 91d70da656..a17dfd1e22 100644 --- a/arch/arm/cpu/tegra-common/ap.c +++ b/arch/arm/cpu/tegra-common/ap.c @@ -163,4 +163,7 @@ void s_init(void) /* init the cache */ config_cache(); + + /* init vpr */ + config_vpr(); } diff --git a/arch/arm/cpu/tegra-common/vpr.c b/arch/arm/cpu/tegra-common/vpr.c new file mode 100644 index 0000000000..f695811c9b --- /dev/null +++ b/arch/arm/cpu/tegra-common/vpr.c @@ -0,0 +1,35 @@ +/* + * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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 . + */ + +/* Tegra vpr routines */ + +#include +#include +#include +#include + +/* Configures VPR. Right now, all we do is turn it off. */ +void config_vpr(void) +{ + struct mc_ctlr *mc = (struct mc_ctlr *)NV_PA_MC_BASE; + + /* Turn VPR off */ + writel(0, &mc->mc_video_protect_size_mb); + writel(TEGRA_MC_VIDEO_PROTECT_REG_WRITE_ACCESS_DISABLED, + &mc->mc_video_protect_reg_ctrl); + /* read back to ensure the write went through */ + readl(&mc->mc_video_protect_reg_ctrl); +} -- cgit v1.2.1