drivers/intel/fsp2_0: Do AP re-init after FSP-S if USE_INTEL_FSP_MP_INIT enable
This patch ensures that coreboot is able to take control of APs back
by doing a full AP re-initialization after FSP-S is done.
TEST=Able to see all cores available after booting to OS using below command
when coreboot is built with USE_INTEL_FSP_MP_INIT enable.
> cat /proc/cpuinfo
Without this CL :
shows only 1 core (only BSP)
With this CL :
shows all possible cores available (BSP + APs)
Change-Id: I247d8d1166c77bd01922323b6a0f14ec6640a666
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44077
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/src/drivers/intel/fsp2_0/Makefile.inc b/src/drivers/intel/fsp2_0/Makefile.inc
index e954a46..32140f4 100644
--- a/src/drivers/intel/fsp2_0/Makefile.inc
+++ b/src/drivers/intel/fsp2_0/Makefile.inc
@@ -14,6 +14,7 @@
romstage-y += cbmem.c
ramstage-y += debug.c
+ramstage-$(CONFIG_USE_INTEL_FSP_MP_INIT) += fsp_mpinit.c
ramstage-$(CONFIG_RUN_FSP_GOP) += graphics.c
ramstage-y += hand_off_block.c
ramstage-$(CONFIG_DISPLAY_FSP_HEADER) += header_display.c
diff --git a/src/drivers/intel/fsp2_0/fsp_mpinit.c b/src/drivers/intel/fsp2_0/fsp_mpinit.c
new file mode 100644
index 0000000..cda9269
--- /dev/null
+++ b/src/drivers/intel/fsp2_0/fsp_mpinit.c
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <fsp/api.h>
+#include <intelblocks/mp_init.h>
+
+/*
+ * As per FSP integration guide:
+ * If bootloader needs to take control of APs back, a full AP re-initialization is
+ * required after FSP-S is completed and control has been transferred back to bootloader
+ */
+void do_mpinit_after_fsp(void)
+{
+ init_cpus();
+}
diff --git a/src/drivers/intel/fsp2_0/include/fsp/api.h b/src/drivers/intel/fsp2_0/include/fsp/api.h
index d2c556f..e0cd96d 100644
--- a/src/drivers/intel/fsp2_0/include/fsp/api.h
+++ b/src/drivers/intel/fsp2_0/include/fsp/api.h
@@ -75,6 +75,13 @@
struct mma_config_param *mma_cfg);
/*
+ * As per FSP integration guide:
+ * If bootloader needs to take control of APs back, a full AP re-initialization is
+ * required after FSP-S is completed and control has been transferred back to bootloader
+ */
+void do_mpinit_after_fsp(void);
+
+/*
* # DOCUMENTATION:
*
* This file defines the interface between coreboot and the FSP 2.0 wrapper
diff --git a/src/drivers/intel/fsp2_0/silicon_init.c b/src/drivers/intel/fsp2_0/silicon_init.c
index 663b1d7..0b6540e 100644
--- a/src/drivers/intel/fsp2_0/silicon_init.c
+++ b/src/drivers/intel/fsp2_0/silicon_init.c
@@ -127,6 +127,10 @@
fsp_debug_after_silicon_init(status);
fsps_return_value_handler(FSP_SILICON_INIT_API, status);
+ /* Reinitialize CPUs if FSP-S has done MP Init */
+ if (CONFIG(USE_INTEL_FSP_MP_INIT))
+ do_mpinit_after_fsp();
+
if (!CONFIG(PLATFORM_USES_FSP2_2))
return;