ARM: OMAP3: RX-51: ARM errata 430973 workaround

Closed and signed Nokia X-Loader bootloader stored in RX-51 nand does not set
IBE bit in ACTLR and starting kernel in non-secure mode. So direct write to
ACTLR by our kernel does not working and the code for ARM errata 430973 in
commit 7ce236fcd6fd45b0441a2d49acb2ceb2de2e8a47 that sets IBE bit is a noop.

In order to have workaround for ARM errata 430973 from non-secure world on
RX-51 we needs Secure Monitor Call to set IBE BIT in ACTLR.

This patch adds RX-51 specific secure support code and sets IBE bit in ACTLR
during board init code for ARM errata 430973 workaround.

Note that new function rx51_secure_dispatcher() differs from existing
omap_secure_dispatcher(). It calling omap_smc3() and param[0] is nargs+1.

ARM errata 430973 workaround is needed for thumb-2 ISA compiled userspace
binaries. Without this workaround thumb-2 binaries crashing. So with this
patch it is possible to recompile and run applications/binaries with thumb-2
ISA on RX-51.

Signed-off-by: Ivaylo Dimitrov <freemangordon@abv.bg>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/board-rx51.c b/arch/arm/mach-omap2/board-rx51.c
index 7735105561d8..db168c9627a1 100644
--- a/arch/arm/mach-omap2/board-rx51.c
+++ b/arch/arm/mach-omap2/board-rx51.c
@@ -2,6 +2,8 @@
  * Board support file for Nokia N900 (aka RX-51).
  *
  * Copyright (C) 2007, 2008 Nokia
+ * Copyright (C) 2012 Ivaylo Dimitrov <freemangordon@abv.bg>
+ * Copyright (C) 2013 Pali Rohár <pali.rohar@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -31,7 +33,9 @@
 #include "mux.h"
 #include "gpmc.h"
 #include "pm.h"
+#include "soc.h"
 #include "sdram-nokia.h"
+#include "omap-secure.h"
 
 #define RX51_GPIO_SLEEP_IND 162
 
@@ -103,6 +107,14 @@ static void __init rx51_init(void)
         usb_musb_init(&musb_board_data);
         rx51_peripherals_init();
 
+        if (omap_type() == OMAP2_DEVICE_TYPE_SEC) {
+#ifdef CONFIG_ARM_ERRATA_430973
+                pr_info("RX-51: Enabling ARM errata 430973 workaround\n");
+                /* set IBE to 1 */
+                rx51_secure_update_aux_cr(BIT(6), 0);
+#endif
+        }
+
         /* Ensure SDRC pins are mux'd for self-refresh */
         omap_mux_init_signal("sdrc_cke0", OMAP_PIN_OUTPUT);
         omap_mux_init_signal("sdrc_cke1", OMAP_PIN_OUTPUT);