Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753069AbbELHjd (ORCPT ); Tue, 12 May 2015 03:39:33 -0400 Received: from bhuna.collabora.co.uk ([93.93.135.160]:43975 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752831AbbELHjY (ORCPT ); Tue, 12 May 2015 03:39:24 -0400 From: Sjoerd Simons To: Rob Herring , Russell King , Tony Lindgren Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Javier Martinez Canillas Subject: [PATCH 1/2] ARM: cache-l2c: Detect whether it's safe to unlock Date: Tue, 12 May 2015 09:39:14 +0200 Message-Id: <1431416355-7693-2-git-send-email-sjoerd.simons@collabora.co.uk> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1431416355-7693-1-git-send-email-sjoerd.simons@collabora.co.uk> References: <1431416355-7693-1-git-send-email-sjoerd.simons@collabora.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3996 Lines: 115 The L2C cache should only be unlocked when the cache is setup to allow that. In the common case the l2x0 driver sets up the cache for that to be the case (e.g. setting L310_AUX_CTRL_NS_LOCKDOWN on L2C-310), making unlock safe. However when a secure firmware is in use, it may not be possible for the L2c to be configured that way making unlocking unsafe. To handle that, for caches where special configuration is needed to allow unlocking, check whether this has been setup before unlocking. Signed-off-by: Sjoerd Simons --- arch/arm/mm/cache-l2x0.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c index e309c8f..2563458 100644 --- a/arch/arm/mm/cache-l2x0.c +++ b/arch/arm/mm/cache-l2x0.c @@ -42,6 +42,7 @@ struct l2c_init_data { void (*fixup)(void __iomem *, u32, struct outer_cache_fns *); void (*save)(void __iomem *); void (*configure)(void __iomem *); + bool (*can_unlock)(void __iomem *); struct outer_cache_fns outer_cache; }; @@ -100,6 +101,9 @@ static inline void l2c_unlock(void __iomem *base, unsigned num) { unsigned i; + if (l2x0_data->can_unlock && !l2x0_data->can_unlock(base)) + return; + for (i = 0; i < num; i++) { writel_relaxed(0, base + L2X0_LOCKDOWN_WAY_D_BASE + i * L2X0_LOCKDOWN_STRIDE); @@ -403,12 +407,18 @@ static void l2c220_enable(void __iomem *base, u32 aux, unsigned num_lock) l2c_enable(base, aux, num_lock); } +static bool l2c220_can_unlock(void __iomem *base) +{ + return readl_relaxed(base + L2X0_AUX_CTRL) & L220_AUX_CTRL_NS_LOCKDOWN; +} + static const struct l2c_init_data l2c220_data = { .type = "L2C-220", .way_size_0 = SZ_8K, .num_lock = 1, .enable = l2c220_enable, .save = l2c_save, + .can_unlock = l2c220_can_unlock, .outer_cache = { .inv_range = l2c220_inv_range, .clean_range = l2c220_clean_range, @@ -681,6 +691,11 @@ static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock) } } +static bool l2c310_can_unlock(void __iomem *base) +{ + return readl_relaxed(base + L2X0_AUX_CTRL) & L310_AUX_CTRL_NS_LOCKDOWN; +} + static void __init l2c310_fixup(void __iomem *base, u32 cache_id, struct outer_cache_fns *fns) { @@ -763,6 +778,7 @@ static const struct l2c_init_data l2c310_init_fns __initconst = { .fixup = l2c310_fixup, .save = l2c310_save, .configure = l2c310_configure, + .can_unlock = l2c310_can_unlock, .outer_cache = { .inv_range = l2c210_inv_range, .clean_range = l2c210_clean_range, @@ -1084,6 +1100,7 @@ static const struct l2c_init_data of_l2c220_data __initconst = { .of_parse = l2x0_of_parse, .enable = l2c220_enable, .save = l2c_save, + .can_unlock = l2c220_can_unlock, .outer_cache = { .inv_range = l2c220_inv_range, .clean_range = l2c220_clean_range, @@ -1211,6 +1228,7 @@ static const struct l2c_init_data of_l2c310_data __initconst = { .fixup = l2c310_fixup, .save = l2c310_save, .configure = l2c310_configure, + .can_unlock = l2c310_can_unlock, .outer_cache = { .inv_range = l2c210_inv_range, .clean_range = l2c210_clean_range, @@ -1240,6 +1258,7 @@ static const struct l2c_init_data of_l2c310_coherent_data __initconst = { .fixup = l2c310_fixup, .save = l2c310_save, .configure = l2c310_configure, + .can_unlock = l2c310_can_unlock, .outer_cache = { .inv_range = l2c210_inv_range, .clean_range = l2c210_clean_range, @@ -1585,6 +1604,7 @@ static const struct l2c_init_data of_bcm_l2x0_data __initconst = { .enable = l2c310_enable, .save = l2c310_save, .configure = l2c310_configure, + .can_unlock = l2c310_can_unlock, .outer_cache = { .inv_range = bcm_inv_range, .clean_range = bcm_clean_range, -- 2.1.4 -- 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/