Tegra: memctrl_v1: disable AHB redirection after cold boot
During boot, USB3 and flash media (SDMMC/SATA) devices need access to
IRAM. Because these clients connect to the MC and do not have a direct
path to the IRAM, the MC implements AHB redirection during boot to allow
path to IRAM. In this mode, accesses to a programmed memory address aperture
are directed to the AHB bus, allowing access to the IRAM. The AHB aperture
is defined by the IRAM_BASE_LO and IRAM_BASE_HI registers, which are
initialized to disable this aperture. Once bootup is complete, we must
program IRAM base/top, thus disabling access to IRAM.
This patch provides functionality to disable this access. The tegra port
calls this new function before jumping to the non-secure world during
cold boot.
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/common/tegra_bl31_setup.c b/plat/nvidia/tegra/common/tegra_bl31_setup.c
index 9e7e576..d2a6be5 100644
--- a/plat/nvidia/tegra/common/tegra_bl31_setup.c
+++ b/plat/nvidia/tegra/common/tegra_bl31_setup.c
@@ -299,7 +299,16 @@
******************************************************************************/
void bl31_plat_runtime_setup(void)
{
- ; /* do nothing */
+ /*
+ * During boot, USB3 and flash media (SDMMC/SATA) devices need
+ * access to IRAM. Because these clients connect to the MC and
+ * do not have a direct path to the IRAM, the MC implements AHB
+ * redirection during boot to allow path to IRAM. In this mode
+ * accesses to a programmed memory address aperture are directed
+ * to the AHB bus, allowing access to the IRAM. This mode must be
+ * disabled before we jump to the non-secure world.
+ */
+ tegra_memctrl_disable_ahb_redirection();
}
/*******************************************************************************