AArch32: Add support to PSCI lib
This patch adds AArch32 support to PSCI library, as follows :
* The `psci_helpers.S` is implemented for AArch32.
* AArch32 version of internal helper function `psci_get_ns_ep_info()` is
defined.
* The PSCI Library is responsible for the Non Secure context initialization.
Hence a library interface `psci_prepare_next_non_secure_ctx()` is introduced
to enable EL3 runtime firmware to initialize the non secure context without
invoking context management library APIs.
Change-Id: I25595b0cc2dbfdf39dbf7c589b875cba33317b9d
diff --git a/lib/psci/psci_common.c b/lib/psci/psci_common.c
index e87e8c0..68cdd6e 100644
--- a/lib/psci/psci_common.c
+++ b/lib/psci/psci_common.c
@@ -592,6 +592,53 @@
* This function determines the full entrypoint information for the requested
* PSCI entrypoint on power on/resume and returns it.
******************************************************************************/
+#ifdef AARCH32
+static int psci_get_ns_ep_info(entry_point_info_t *ep,
+ uintptr_t entrypoint,
+ u_register_t context_id)
+{
+ u_register_t ep_attr;
+ unsigned int aif, ee, mode;
+ u_register_t scr = read_scr();
+ u_register_t ns_sctlr, sctlr;
+
+ /* Switch to non secure state */
+ write_scr(scr | SCR_NS_BIT);
+ isb();
+ ns_sctlr = read_sctlr();
+
+ sctlr = scr & SCR_HCE_BIT ? read_hsctlr() : ns_sctlr;
+
+ /* Return to original state */
+ write_scr(scr);
+ isb();
+ ee = 0;
+
+ ep_attr = NON_SECURE | EP_ST_DISABLE;
+ if (sctlr & SCTLR_EE_BIT) {
+ ep_attr |= EP_EE_BIG;
+ ee = 1;
+ }
+ SET_PARAM_HEAD(ep, PARAM_EP, VERSION_1, ep_attr);
+
+ ep->pc = entrypoint;
+ memset(&ep->args, 0, sizeof(ep->args));
+ ep->args.arg0 = context_id;
+
+ mode = scr & SCR_HCE_BIT ? MODE32_hyp : MODE32_svc;
+
+ /*
+ * TODO: Choose async. exception bits if HYP mode is not
+ * implemented according to the values of SCR.{AW, FW} bits
+ */
+ aif = SPSR_ABT_BIT | SPSR_IRQ_BIT | SPSR_FIQ_BIT;
+
+ ep->spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, aif);
+
+ return PSCI_E_SUCCESS;
+}
+
+#else
static int psci_get_ns_ep_info(entry_point_info_t *ep,
uintptr_t entrypoint,
u_register_t context_id)
@@ -646,6 +693,7 @@
return PSCI_E_SUCCESS;
}
+#endif
/*******************************************************************************
* This function validates the entrypoint with the platform layer if the