mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Rouven Czerwinski <r.czerwinski@pengutronix.de>
To: barebox@lists.infradead.org
Cc: Rouven Czerwinski <r.czerwinski@pengutronix.de>
Subject: [PATCH v2 4/5] ARM: mach-imx: test PL310 write access
Date: Mon, 20 Jan 2020 09:56:47 +0100	[thread overview]
Message-ID: <20200120085647.19784-4-r.czerwinski@pengutronix.de> (raw)
In-Reply-To: <20200120085647.19784-1-r.czerwinski@pengutronix.de>

If OP-TEE early loading is performed, OP-TEE will configure the PL210
and lock write access to the controller from the normal world. Test this
by trying to write the same value back and do not configure if we can
not write to the PL310.

Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>
---
 arch/arm/mach-imx/imx6.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/arm/mach-imx/imx6.c b/arch/arm/mach-imx/imx6.c
index 41e0066add..c6fd862379 100644
--- a/arch/arm/mach-imx/imx6.c
+++ b/arch/arm/mach-imx/imx6.c
@@ -11,6 +11,7 @@
  *
  */
 
+#include <abort.h>
 #include <init.h>
 #include <common.h>
 #include <io.h>
@@ -273,6 +274,22 @@ int imx6_devices_init(void)
 	return 0;
 }
 
+static bool imx6_can_write_l2x0(void)
+{
+	void __iomem *l2x0_base = IOMEM(0x00a02000);
+	u32 val;
+	/*
+	 * Mask data aborts and try to access the PL210. If OP-TEE is running we
+	 * will receive a data-abort and assume barebox is running in the normal
+	 * world.
+	 */
+	val = readl(l2x0_base + L2X0_PREFETCH_CTRL);
+
+	data_abort_mask();
+	writel(val, l2x0_base + L2X0_PREFETCH_CTRL);
+	return data_abort_unmask();
+}
+
 static int imx6_mmu_init(void)
 {
 	void __iomem *l2x0_base = IOMEM(0x00a02000);
@@ -281,6 +298,9 @@ static int imx6_mmu_init(void)
 	if (!cpu_is_mx6())
 		return 0;
 
+	if (imx6_can_write_l2x0())
+		return 0;
+
 	val = readl(l2x0_base + L2X0_CACHE_ID);
 	cache_part = val & L2X0_CACHE_ID_PART_MASK;
 	cache_rtl  = val & L2X0_CACHE_ID_RTL_MASK;
-- 
2.25.0


_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

  parent reply	other threads:[~2020-01-20  8:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-20  8:56 [PATCH v2 1/5] optee: move optee_verify_header() to common Rouven Czerwinski
2020-01-20  8:56 ` [PATCH v2 2/5] ARM: import setjmp implementation from U-Boot Rouven Czerwinski
2020-01-21  7:46   ` Sascha Hauer
2020-01-20  8:56 ` [PATCH v2 3/5] ARM: add optee early loading function Rouven Czerwinski
2020-01-20  8:56 ` Rouven Czerwinski [this message]
2020-01-21  7:37   ` [PATCH v2 4/5] ARM: mach-imx: test PL310 write access Sascha Hauer
2020-01-20  8:56 ` [PATCH v2 5/5] user: add documentation for OP-TEE loading Rouven Czerwinski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200120085647.19784-4-r.czerwinski@pengutronix.de \
    --to=r.czerwinski@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox