core: add support for transfer list

Add supports for Transfer List on both aarch32/64.
Fetch arguments from {x,r}{0-3} and check if a valid Transfer List
exists, which compliant to the Firmware Handoff specification.
The Transfer List will be mapped during early initialization and
unmapped before exiting to next boot stage.
DTB and pagable address will be parsed from the Transfer List if
they exist as Transfer Entries.
If Transfer List does not exist or is invalid, legacy argument
handoff is backwards compatible.

Signed-off-by: Raymond Mao <raymond.mao@linaro.org>

core/arch/arm/kernel/boot.c

@@ -15,6 +15,7 @@
 #include <ffa.h>
 #include <initcall.h>
 #include <inttypes.h>
+#include <io.h>
 #include <keep.h>
 #include <kernel/asan.h>
 #include <kernel/boot.h>
@@ -1253,13 +1254,30 @@ static void init_secondary_helper(unsigned long nsec_entry)
  * the unpaged area so that it lies in the init area.
  */
 void __weak boot_init_primary_early(unsigned long pageable_part,
-				    unsigned long nsec_entry __maybe_unused)
+				    unsigned long nsec_entry __maybe_unused,
+				    unsigned long transfer_list)
 {
 	unsigned long e = PADDR_INVALID;
+	struct transfer_list_entry *te = NULL;
+	struct transfer_list_header *tl = NULL;
+	struct dt_descriptor *dt = get_external_dt_desc();
 
 #if !defined(CFG_WITH_ARM_TRUSTED_FW)
 	e = nsec_entry;
 #endif
+	if (IS_ENABLED(CFG_TRANSFER_LIST) && transfer_list) {
+		/* map the TL */
+		tl = transfer_list_map(transfer_list);
+		if (!tl)
+			panic("Failed to map transfer list");
+		dt->tl = tl; /* save the mapped TL */
+
+		te = transfer_list_find(tl, TL_TAG_OPTEE_PAGABLE_PART);
+		if (IS_ENABLED(CFG_WITH_PAGER) && !pageable_part && te) {
+			pageable_part = get_le64(transfer_list_entry_data(te));
+			transfer_list_rem(tl, te);
+		}
+	}
 
 	init_primary(pageable_part, e);
 }
@@ -1321,7 +1339,7 @@ struct ns_entry_context *boot_core_hpen(void)
 
 #if defined(CFG_CORE_ASLR)
 #if defined(CFG_DT)
-unsigned long __weak get_aslr_seed(void *fdt)
+unsigned long __weak get_aslr_seed(void *fdt, struct transfer_list_header *tl)
 {
 	int rc = 0;
 	const uint64_t *seed = NULL;
@@ -1333,6 +1351,14 @@ unsigned long __weak get_aslr_seed(void *fdt)
 		goto err;
 	}
 
+	if (tl && IS_ENABLED(CFG_TRANSFER_LIST)) {
+		if (fdt != transfer_list_entry_data
+			(transfer_list_find(tl,	TL_TAG_FDT))) {
+			EMSG("fdt does not match to the fdt entry of the TL");
+			goto err;
+		}
+	}
+
 	rc = fdt_check_header(fdt);
 	if (rc) {
 		DMSG("Bad fdt: %d", rc);
@@ -1357,7 +1383,8 @@ unsigned long __weak get_aslr_seed(void *fdt)
 	return plat_get_aslr_seed();
 }
 #else /*!CFG_DT*/
-unsigned long __weak get_aslr_seed(void *fdt __unused)
+unsigned long __weak get_aslr_seed(void *fdt __unused,
+				   struct transfer_list_header *tl __unused)
 {
 	/* Try platform implementation */
 	return plat_get_aslr_seed();

core/arch/arm/kernel/entry_a32.S

@@ -12,6 +12,7 @@
 #include <kernel/asan.h>
 #include <kernel/cache_helpers.h>
 #include <kernel/thread_private.h>
+#include <kernel/transfer_list.h>
 #include <mm/core_mmu.h>
 #include <platform_config.h>
 #include <sm/optee_smc.h>
@@ -162,6 +163,24 @@ END_FUNC reset_vect_table
 #endif
 		write_sctlr r0
 	.endm
+#if defined(CFG_TRANSFER_LIST)
+	/*
+	 * FW Handoff register use:
+	 * entry r0: Zero
+	 * entry r1: TRANSFER_LIST_SIGNATURE | REGISTER_CONVENTION_VERSION_MASK
+	 * entry r2, saved r6: device tree address
+	 * entry r3, saved r10: Transfer list base address
+	 * saved r4, r7: Zero
+	 * entry lr, saved r5: non-secure entry address
+	 */
+	.macro bootargs_entry_tl
+	mov	r5, lr	/* non-secure entry address */
+	mov	r4, #0	/* Pagable or TOS FW config address is in TL */
+	mov	r6, r2	/* Save DT address */
+	mov	r7, #0
+	mov	r10, r3	/* Save TL address */
+	.endm
+#endif
 
 #if defined(CFG_CORE_SEL1_SPMC) && defined(CFG_WITH_ARM_TRUSTED_FW)
 	/*
@@ -179,6 +198,7 @@ END_FUNC reset_vect_table
 	mov	r4, r1
 	mov	r5, #0
 	mov	r7, #0
+	mov	r10, #0
 	.endm
 #else
 	/*
@@ -205,6 +225,7 @@ END_FUNC reset_vect_table
 	mov	r6, r2
 #endif
 	mov	r7, r1
+	mov	r10, #0
 	.endm
 #endif
 
@@ -239,8 +260,20 @@ END_FUNC reset_vect_table
 
 FUNC _start , :
 UNWIND(	.cantunwind)
-
+#if defined(CFG_TRANSFER_LIST)
+	/* check if the TL signature exists */
+	ldr     r4, =TRANSFER_LIST_SIGNATURE
+	ldr     r5, =REGISTER_CONVENTION_VERSION_MASK
+	orr     r6, r4, r5
+	cmp	r1, r6
+	bne	no_tl_sig
+	/* TL signature exists */
+	bootargs_entry_tl
+	b	sav_arg_done
+no_tl_sig:	/* TL signature does not exist, legacy mode */
+#endif
 	bootargs_entry
+sav_arg_done:	/* arguments saved */
 
 	/*
 	 * 32bit entry is expected to execute Supervisor mode,
@@ -365,7 +398,7 @@ DECLARE_KEEP_INIT _start
 LOCAL_FUNC reset_primary , : , .identity_map
 UNWIND(	.cantunwind)
 
-	/* preserve r4-r7: bootargs */
+	/* preserve r4-r7 and r10: bootargs */
 
 #ifdef CFG_WITH_PAGER
 	/*
@@ -390,8 +423,8 @@ UNWIND(	.cantunwind)
 	str	r0, cached_mem_end
 	ldr	r2, =__init_start
 copy_init:
-	ldmdb	r1!, {r3, r8-r12}
-	stmdb	r0!, {r3, r8-r12}
+	ldmdb	r1!, {r3, r8-r9, r11-r12}
+	stmdb	r0!, {r3, r8-r9, r11-r12}
 	cmp	r0, r2
 	bgt	copy_init
 #else
@@ -411,8 +444,8 @@ copy_init:
 	ldr	r2, =__end
 
 copy_init:
-	ldmdb	r1!, {r3, r8-r12}
-	stmdb	r0!, {r3, r8-r12}
+	ldmdb	r1!, {r3, r8-r9, r11-r12}
+	stmdb	r0!, {r3, r8-r9, r11-r12}
 	cmp	r0, r2
 	bgt	copy_init
 #endif
@@ -499,8 +532,20 @@ shadow_stack_access_ok:
 	bl	arm_cl2_enable
 #endif
 
+#if defined(CFG_TRANSFER_LIST)
+	/* check if the TL header valid */
+	mov	r0, r10
+	bl	transfer_list_check_header
+	ldr	r1, =TL_OPS_NON
+	cmp	r0, r1
+	bne	tl_valid
+	mov	r10, #0		/* clean the address if TL is invalid */
+tl_valid:
+#endif
+
 #ifdef CFG_CORE_ASLR
-	mov	r0, r6
+	mov	r0, r6		/* DT address */
+	mov	r1, r10		/* TL address */
 	bl	get_aslr_seed
 #else
 	mov	r0, #0
@@ -549,6 +594,7 @@ shadow_stack_access_ok:
 
 	mov	r0, r4		/* pageable part address */
 	mov	r1, r5		/* ns-entry address */
+	mov	r2, r10		/* TL address */
 	bl	boot_init_primary_early
 #ifndef CFG_NS_VIRTUALIZATION
 	mov	r9, sp
@@ -562,6 +608,7 @@ shadow_stack_access_ok:
 #endif
 	mov	r0, r6		/* DT address */
 	mov	r1, #0		/* unused */
+	/* PA of TL is not needed as it is already mapped */
 	bl	boot_init_primary_late
 #ifndef CFG_NS_VIRTUALIZATION
 	mov	r0, #THREAD_CLF_TMP

core/arch/arm/kernel/entry_a64.S

@@ -12,6 +12,7 @@
 #include <generated/asm-defines.h>
 #include <keep.h>
 #include <kernel/thread_private.h>
+#include <kernel/transfer_list.h>
 #include <mm/core_mmu.h>
 #include <sm/optee_smc.h>
 #include <sm/teesmc_opteed.h>
@@ -160,8 +161,28 @@
 	.endm
 
 FUNC _start , :
+#if defined(CFG_TRANSFER_LIST)
 	/*
-	 * Register use:
+	 * FW Handoff register use:
+	 * x0	- DTB address or 0
+	 * x1	- TRANSFER_LIST_SIGNATURE | REGISTER_CONVENTION_VERSION_MASK
+	 * x2	- 0
+	 * x3	- Transfer list base address
+	 *
+	 * x19	- 0
+	 * x20	- saved x0
+	 * x23	- saved x3
+	 */
+	/* check if the TL signature exists */
+	ldr     x19, =TRANSFER_LIST_SIGNATURE
+	ldr     x20, =REGISTER_CONVENTION_VERSION_MASK
+	orr     x23, x19, x20
+	cmp	x1, x23
+	b.eq	tl_sig_exist
+#endif
+	/* Transfer list signature does not exist, legacy mode
+	 *
+	 * Legacy register use:
 	 * x0	- CFG_CORE_FFA=y && CFG_CORE_SEL2_SPMC=n:
 	 *	  if non-NULL holds the TOS FW config [1] address
 	 *	- CFG_CORE_FFA=y && CFG_CORE_SEL2_SPMC=y:
@@ -173,6 +194,7 @@ FUNC _start , :
 	 *
 	 * x19 - saved x0
 	 * x20 - saved x2
+	 * x23 - 0
 	 *
 	 * [1] A TF-A concept: TOS_FW_CONFIG - Trusted OS Firmware
 	 * configuration file. Used by Trusted OS (BL32), that is, OP-TEE
@@ -184,7 +206,15 @@ FUNC _start , :
 #else
 	mov	x20, x2		/* Save DT address */
 #endif
+	mov	x23, #0
+	b	sav_arg_done
+
+tl_sig_exist:	/* Transfer list signature exists */
+	mov	x19, #0		/* Pagable or TOS FW config address is in TL */
+	mov	x20, x0		/* Save DT address */
+	mov	x23, x3		/* Save TL address */
 
+sav_arg_done:	/* arguments saved */
 	adr	x0, reset_vect_table
 	msr	vbar_el1, x0
 	isb
@@ -326,8 +356,20 @@ clear_nex_bss:
 	bl	boot_init_memtag
 #endif
 
+#if defined(CFG_TRANSFER_LIST)
+	/* check if the TL header valid */
+	mov	x0, x23
+	bl	transfer_list_check_header
+	ldr	x1, =TL_OPS_NON
+	cmp	x0, x1
+	b.ne	tl_valid
+	mov	x23, #0		/* clean the address if TL is invalid */
+tl_valid:
+#endif
+
 #ifdef CFG_CORE_ASLR
 	mov	x0, x20		/* DT address */
+	mov	x1, x23		/* TL address */
 	bl	get_aslr_seed
 #else
 	mov	x0, #0
@@ -382,6 +424,7 @@ clear_nex_bss:
 	mov	x0, x19		/* pagable part address */
 #endif
 	mov	x1, #-1
+	mov	x2, x23		/* TL address */
 	bl	boot_init_primary_early
 
 #ifdef CFG_MEMTAG
@@ -403,6 +446,7 @@ clear_nex_bss:
 #else
 	mov	x1, xzr		/* unused */
 #endif
+	/* PA of TL is not needed as it is already mapped */
 	bl	boot_init_primary_late
 #ifdef CFG_CORE_PAUTH
 	init_pauth_per_cpu

core/arch/arm/kernel/link_dummies_init.c

@@ -12,7 +12,7 @@ boot_save_boot_info(void *boot_info __unused)
 }
 
 unsigned long __section(".text.dummy.get_aslr_seed")
-get_aslr_seed(void *fdt __unused)
+get_aslr_seed(void *fdt __unused, struct transfer_list_header *tl __unused)
 {
 	return 0;
 }
@@ -25,6 +25,7 @@ core_init_mmu_map(unsigned long seed __unused,
 
 void __section(".text.dummy.boot_init_primary_early")
 boot_init_primary_early(unsigned long pageable_part __unused,
-			unsigned long nsec_entry __unused)
+			unsigned long nsec_entry __unused,
+			unsigned long transfer_list __unused)
 {
 }

core/include/kernel/boot.h

@@ -7,6 +7,7 @@
 #define __KERNEL_BOOT_H
 
 #include <initcall.h>
+#include <kernel/transfer_list.h>
 #include <types_ext.h>
 
 /*
@@ -44,7 +45,8 @@ extern const struct core_mmu_config boot_mmu_config;
 
 /* @nsec_entry is unused if using CFG_WITH_ARM_TRUSTED_FW */
 void boot_init_primary_early(unsigned long pageable_part,
-			     unsigned long nsec_entry);
+			     unsigned long nsec_entry,
+			     unsigned long transfer_list);
 void boot_init_primary_late(unsigned long fdt, unsigned long manifest);
 void boot_init_memtag(void);
 void boot_save_boot_info(void *boot_info);
@@ -97,9 +99,10 @@ void *get_manifest_dt(void);
 /*
  * get_aslr_seed() - return a random seed for core ASLR
  * @fdt:	Pointer to a device tree if CFG_DT_ADDR=y
+ * @tl:		Pointer to a transfer list
  *
  * This function has a __weak default implementation.
  */
-unsigned long get_aslr_seed(void *fdt);
+unsigned long get_aslr_seed(void *fdt, struct transfer_list_header *tl);
 
 #endif /* __KERNEL_BOOT_H */

core/include/kernel/dt.h

@@ -83,6 +83,7 @@ struct dt_descriptor {
 #ifdef _CFG_USE_DTB_OVERLAY
 	int frag_id;
 #endif
+	struct transfer_list_header *tl;
 };
 
 extern uint8_t embedded_secure_dtb[];

core/include/mm/core_mmu.h

@@ -77,6 +77,7 @@
  * MEM_AREA_IO_SEC:   Secure HW mapped registers
  * MEM_AREA_EXT_DT:   Memory loads external device tree
  * MEM_AREA_MANIFEST_DT: Memory loads manifest device tree
+ * MEM_AREA_TRANSFER_LIST: Memory area mapped for Transfer List
  * MEM_AREA_RES_VASPACE: Reserved virtual memory space
  * MEM_AREA_SHM_VASPACE: Virtual memory space for dynamic shared memory buffers
  * MEM_AREA_TS_VASPACE: TS va space, only used with phys_to_virt()