1 // SPDX-License-Identifier: GPL-2.0-only
3  * FF-A v1.0 proxy to filter out invalid memory-sharing SMC calls issued by
4  * the host. FF-A is a slightly more palatable abbreviation of "Arm Firmware
5  * Framework for Arm A-profile", which is specified by Arm in document
8  * Copyright (C) 2022 - Google LLC
12  * all calls falling within the FF-A range. Each call is either:
14  *	- Forwarded on unmodified to the SPMD at EL3
15  *	- Rejected as "unsupported"
16  *	- Accompanied by a host stage-2 page-table check/update and reissued
19  * accessible to the secure world using FF-A will be detected either here
22  * with the secure world).
24  * To allow the rolling-back of page-table updates and FF-A calls in the
29 #include <linux/arm-smccc.h>
40  * "ID value 0 must be returned at the Non-secure physical FF-A instance"
97 	cpu_reg(ctxt, 0) = res->a0;  in ffa_set_retval()
98 	cpu_reg(ctxt, 1) = res->a1;  in ffa_set_retval()
99 	cpu_reg(ctxt, 2) = res->a2;  in ffa_set_retval()
100 	cpu_reg(ctxt, 3) = res->a3;  in ffa_set_retval()
299 		u64 sz = (u64)range->pg_cnt * FFA_PAGE_SIZE;  in __ffa_host_share_ranges()
300 		u64 pfn = hyp_phys_to_pfn(range->address);  in __ffa_host_share_ranges()
319 		u64 sz = (u64)range->pg_cnt * FFA_PAGE_SIZE;  in __ffa_host_unshare_ranges()
320 		u64 pfn = hyp_phys_to_pfn(range->address);  in __ffa_host_unshare_ranges()
393 		WARN_ON(res->a0 != FFA_SUCCESS);  in do_ffa_mem_frag_tx()
398 	if (res->a0 != FFA_SUCCESS && res->a0 != FFA_MEM_FRAG_RX)  in do_ffa_mem_frag_tx()
410 	 * the host stage-2 changes. The pages previously marked as shared will  in do_ffa_mem_frag_tx()
427 	struct ffa_composite_mem_region *reg;  in do_ffa_mem_xfer()  local
458 	offset = ep_mem_access->composite_off;  in do_ffa_mem_xfer()
459 	if (!offset || buf->ep_count != 1 || buf->sender_id != HOST_FFA_ID) {  in do_ffa_mem_xfer()
469 	reg = (void *)buf + offset;  in do_ffa_mem_xfer()
470 	nr_ranges = ((void *)buf + fraglen) - (void *)reg->constituents;  in do_ffa_mem_xfer()
471 	if (nr_ranges % sizeof(reg->constituents[0])) {  in do_ffa_mem_xfer()
476 	nr_ranges /= sizeof(reg->constituents[0]);  in do_ffa_mem_xfer()
477 	ret = ffa_host_share_ranges(reg->constituents, nr_ranges);  in do_ffa_mem_xfer()
483 		if (res->a0 != FFA_MEM_FRAG_RX)  in do_ffa_mem_xfer()
486 		if (res->a3 != fraglen)  in do_ffa_mem_xfer()
488 	} else if (res->a0 != FFA_SUCCESS) {  in do_ffa_mem_xfer()
500 	WARN_ON(ffa_host_unshare_ranges(reg->constituents, nr_ranges));  in do_ffa_mem_xfer()
511 	struct ffa_composite_mem_region *reg;  in do_ffa_mem_reclaim()  local
529 	if (res->a0 != FFA_MEM_RETRIEVE_RESP)  in do_ffa_mem_reclaim()
532 	len = res->a1;  in do_ffa_mem_reclaim()
533 	fraglen = res->a2;  in do_ffa_mem_reclaim()
537 	offset = ep_mem_access->composite_off;  in do_ffa_mem_reclaim()
559 		if (res->a0 != FFA_MEM_FRAG_TX) {  in do_ffa_mem_reclaim()
564 		fraglen = res->a3;  in do_ffa_mem_reclaim()
569 	if (res->a0 != FFA_SUCCESS)  in do_ffa_mem_reclaim()
572 	reg = (void *)buf + offset;  in do_ffa_mem_reclaim()
574 	WARN_ON(ffa_host_unshare_ranges(reg->constituents,  in do_ffa_mem_reclaim()
575 					reg->addr_range_cnt));  in do_ffa_mem_reclaim()
602 	/* 32-bit variants of 64-bit calls */  in ffa_call_supported()
648 	 * There's no way we can tell what a non-standard SMC call might  in kvm_host_ffa_handler()
652 	 * RNG access and crash reporting.  in kvm_host_ffa_handler()
656 	 * the firmware doesn't expose a mechanism to access arbitrary  in kvm_host_ffa_handler()
657 	 * non-secure memory. Short of a per-device table of SMCs, this  in kvm_host_ffa_handler()
714 	 * Firmware returns the maximum supported version of the FF-A  in hyp_ffa_init()
716 	 * backwards-compatible with the hyp according to the rules in DEN0077A  in hyp_ffa_init()
727 		return -EOPNOTSUPP;  in hyp_ffa_init()
731 		return -EOPNOTSUPP;  in hyp_ffa_init()
734 		return -EINVAL;  in hyp_ffa_init()
739 		return -EOPNOTSUPP;  in hyp_ffa_init()
752 		return -EINVAL;  in hyp_ffa_init()
756 		return -EOPNOTSUPP;  in hyp_ffa_init()
766 			  (hyp_ffa_proxy_pages() - (2 * KVM_FFA_MBOX_NR_PAGES)),  in hyp_ffa_init()