@@ -30,6 +30,8 @@
#include <linux/printk.h>
#include <linux/bug.h>
#include <linux/of.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
struct trusted_foundations_platform_data {
unsigned int version_major;
@@ -47,10 +49,13 @@ static inline void register_trusted_foundations(
struct trusted_foundations_platform_data *pd)
{
/*
- * If we try to register TF, this means the system needs it to continue.
- * Its absence if thus a fatal error.
+ * If the system requires TF and we cannot provide it, continue booting
+ * but disable features that cannot be provided.
*/
- panic("No support for Trusted Foundations, stopping...\n");
+ pr_err("No support for Trusted Foundations, continuing in degraded mode.\n");
+ pr_err("Secondary processors as well as CPU PM will be disabled.\n");
+ setup_max_cpus = 0;
+ cpu_idle_poll_ctrl(true);
}
static inline void of_register_trusted_foundations(void)
When Trusted Foundations is detected as present on the system, but Trusted Foundations support is not built into the kernel, the kernel used to issue a panic very early during boot, leaving little clue to the user as to what is going wrong. It turns out that even without TF support built-in, the kernel can boot on a TF-enabled system provided that SMP and cpuidle are disabled. This patch does this and continue booting on one CPU, leaving the user with a usable (however degraded) system. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> --- arch/arm/include/asm/trusted_foundations.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)