[RFC PATCH 3/5] platform/generic: Initialise MPT at boot

[Rahul Pathak]

Integrates MPT initialisation into the generic platform boot flow.

mpt_early_init() probes for SMMPT during cold-boot early init and
initialises the structures required to build MPT tables.

mpt_final_init() creates the root supervisor domain which is mapping all
physical memory with the firmware region explcitly denied to S-mode and
adds support for an MPT domain for each additional registered SBI domain.

The heap budget is extended to reserve space for MPT tables.

With this patch MPT tables are built at boot.

Signed-off-by: Rahul Pathak <rahul.pathak at oss.qualcomm.com>
---
 platform/generic/platform.c | 101 ++++++++++++++++++++++++++++++++++++
 1 file changed, 101 insertions(+)

diff --git a/platform/generic/platform.c b/platform/generic/platform.c
index 1df0280d..b9a715b6 100644
--- a/platform/generic/platform.c
+++ b/platform/generic/platform.c
@@ -17,6 +17,9 @@
 #include <sbi/sbi_string.h>
 #include <sbi/sbi_system.h>
 #include <sbi/sbi_tlb.h>
+#include <sbi/sbi_mpt.h>
+#include <sbi/sbi_domain.h>
+#include <sbi/sbi_console.h>
 #include <sbi_utils/cache/fdt_cmo_helper.h>
 #include <sbi_utils/fdt/fdt_domain.h>
 #include <sbi_utils/fdt/fdt_driver.h>
@@ -33,6 +36,86 @@
 /* List of platform override modules generated at compile time */
 extern const struct fdt_driver *const platform_override_modules[];
 
+/*
+ * mpt_early_init(): Detects the SMMPT mode and initializes the
+ * structures (not MPT tables) requried to prepare MPT tables and
+ * domain programming.
+ */
+int mpt_early_init(bool cold_boot)
+{
+	int rc;
+
+	if (!cold_boot)
+		return 0;
+
+	rc = sbi_mpt_init();
+	if (rc == SBI_ENODEV)
+		return 0;
+
+	return rc;
+}
+
+/*
+ * mpt_final_init(): Performs the final initialzation including
+ * creation of Root supervisor domain.
+ */
+int mpt_final_init(bool cold_boot)
+{
+	int rc;
+	u32 sdid;
+	struct sbi_domain *dom, *root_dom;
+	struct sbi_mpt_domain_config cfg;
+
+	if (!cold_boot)
+		return 0;
+
+	/* SMMPT may be unavailable */
+	if (!sbi_mpt_ctrl_get()->ready)
+		return 0;
+
+	/*
+	 * Create MPT domain for Root domain.
+	 *
+	 * Root domain maps all physical memory so the
+	 * firmware region must be explicitly denied to S-mode.
+	 *
+	 * regions pointer is NULL and nregions is 0 since there
+	 * are no other regions other than respective SBI domain for mapping.
+	 */
+	root_dom = sbi_domain_thishart_ptr();
+	cfg.sbi_dom = root_dom;
+	cfg.xwr = SBI_MPT_PERM_RWX;
+	cfg.fw_protect = true;
+	cfg.regions = NULL;
+	cfg.nregions = 0;
+
+	rc = sbi_mpt_domain_create(&cfg, &sdid);
+	if (rc) {
+		sbi_printf("mpt: Root domain create failed rc=%d\n", rc);
+		return rc;
+	}
+
+	sbi_memset(&cfg, 0, sizeof(cfg));
+
+	/* Create MPT domain for all other registered SBI domains. */
+	sbi_domain_for_each(dom) {
+		if (dom == root_dom)
+			continue;
+
+		cfg.sbi_dom = dom;
+		cfg.xwr = SBI_MPT_PERM_RWX;
+		cfg.fw_protect = false;
+		cfg.regions = NULL;
+		cfg.nregions = 0;
+
+		rc = sbi_mpt_domain_create(&cfg, &sdid);
+		if (rc)
+			sbi_printf("mpt: domain '%s' failed rc=%d\n", dom->name, rc);
+	}
+
+	return 0;
+}
+
 static u32 fw_platform_calculate_heap_size(u32 hart_count)
 {
 	u32 heap_size;
@@ -42,6 +125,15 @@ static u32 fw_platform_calculate_heap_size(u32 hart_count)
 	/* For TLB fifo */
 	heap_size += SBI_TLB_INFO_SIZE * (hart_count) * (hart_count);
 
+	/*
+	 * MPT table budget
+	 * 1 MiB memory for MPT allocated currently.
+	 *
+	 * TODO: Need better way to get the memory budget based on active
+	 * SMMPT mode.
+	 */
+	heap_size += 1024 * 1024;
+
 	return BIT_ALIGN(heap_size, HEAP_BASE_ALIGN);
 }
 
@@ -229,6 +321,10 @@ int generic_early_init(bool cold_boot)
 			return rc;
 
 		fdt_driver_init_all(fdt, fdt_early_drivers);
+
+		rc = mpt_early_init(cold_boot);
+		if (rc)
+			return rc;
 	}
 
 	return fdt_cmo_init(cold_boot);
@@ -236,11 +332,16 @@ int generic_early_init(bool cold_boot)
 
 int generic_final_init(bool cold_boot)
 {
+	int rc;
 	void *fdt = fdt_get_address_rw();
 
 	if (!cold_boot)
 		return 0;
 
+	rc = mpt_final_init(cold_boot);
+	if (rc)
+		return rc;
+
 	fdt_cpu_fixup(fdt);
 	fdt_fixups(fdt);
 	fdt_domain_fixup(fdt);
-- 
2.51.0