SMCCC/PCI: Handle std svc boilerplate
Add SMC wrappers for handshaking the existence
and basic parameter validation for the SMCCC/PCI
API. The actual read/write/segment validation is
implemented by a given platform which will enable
the API by defining SMC_PCI_SUPPORT.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Change-Id: I4485ad0fe6003cec6f5eedef688914d100513c21
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index 2088533..1fdf545 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -95,6 +95,10 @@
lib/cpus/aarch64/wa_cve_2017_5715_mmu.S
endif
+ifeq ($(SMC_PCI_SUPPORT),1)
+BL31_SOURCES += services/std_svc/pci_svc.c
+endif
+
BL31_LINKERFILE := bl31/bl31.ld.S
# Flag used to indicate if Crash reporting via console should be included
diff --git a/services/std_svc/pci_svc.c b/services/std_svc/pci_svc.c
new file mode 100644
index 0000000..a02b8a7
--- /dev/null
+++ b/services/std_svc/pci_svc.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2021, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <stdint.h>
+
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <services/pci_svc.h>
+#include <services/std_svc.h>
+#include <smccc_helpers.h>
+
+static uint64_t validate_rw_addr_sz(uint32_t addr, uint64_t off, uint64_t sz)
+{
+ uint32_t nseg;
+ uint32_t ret;
+ uint32_t start_end_bus;
+
+ ret = pci_get_bus_for_seg(PCI_ADDR_SEG(addr), &start_end_bus, &nseg);
+
+ if (ret != SMC_PCI_CALL_SUCCESS) {
+ return SMC_PCI_CALL_INVAL_PARAM;
+ }
+ switch (sz) {
+ case SMC_PCI_SZ_8BIT:
+ case SMC_PCI_SZ_16BIT:
+ case SMC_PCI_SZ_32BIT:
+ break;
+ default:
+ return SMC_PCI_CALL_INVAL_PARAM;
+ }
+ if ((off + sz) > (PCI_OFFSET_MASK + 1U)) {
+ return SMC_PCI_CALL_INVAL_PARAM;
+ }
+ return SMC_PCI_CALL_SUCCESS;
+}
+
+uint64_t pci_smc_handler(uint32_t smc_fid,
+ u_register_t x1,
+ u_register_t x2,
+ u_register_t x3,
+ u_register_t x4,
+ void *cookie,
+ void *handle,
+ u_register_t flags)
+{
+ switch (smc_fid) {
+ case SMC_PCI_VERSION: {
+ pcie_version ver;
+
+ ver.major = 1U;
+ ver.minor = 0U;
+ SMC_RET4(handle, ver.val, 0U, 0U, 0U);
+ }
+ case SMC_PCI_FEATURES:
+ switch (x1) {
+ case SMC_PCI_VERSION:
+ case SMC_PCI_FEATURES:
+ case SMC_PCI_READ:
+ case SMC_PCI_WRITE:
+ case SMC_PCI_SEG_INFO:
+ SMC_RET1(handle, SMC_PCI_CALL_SUCCESS);
+ default:
+ SMC_RET1(handle, SMC_PCI_CALL_NOT_SUPPORTED);
+ }
+ break;
+ case SMC_PCI_READ: {
+ uint32_t ret;
+
+ if (validate_rw_addr_sz(x1, x2, x3) != SMC_PCI_CALL_SUCCESS) {
+ SMC_RET2(handle, SMC_PCI_CALL_INVAL_PARAM, 0U);
+ }
+ if (x4 != 0U) {
+ SMC_RET2(handle, SMC_PCI_CALL_INVAL_PARAM, 0U);
+ }
+ if (pci_read_config(x1, x2, x3, &ret) != 0U) {
+ SMC_RET2(handle, SMC_PCI_CALL_INVAL_PARAM, 0U);
+ } else {
+ SMC_RET2(handle, SMC_PCI_CALL_SUCCESS, ret);
+ }
+ break;
+ }
+ case SMC_PCI_WRITE: {
+ uint32_t ret;
+
+ if (validate_rw_addr_sz(x1, x2, x3) != SMC_PCI_CALL_SUCCESS) {
+ SMC_RET1(handle, SMC_PCI_CALL_INVAL_PARAM);
+ }
+ ret = pci_write_config(x1, x2, x3, x4);
+ SMC_RET1(handle, ret);
+ break;
+ }
+ case SMC_PCI_SEG_INFO: {
+ uint32_t nseg;
+ uint32_t ret;
+ uint32_t start_end_bus;
+
+ if ((x2 != 0U) || (x3 != 0U) || (x4 != 0U)) {
+ SMC_RET3(handle, SMC_PCI_CALL_INVAL_PARAM, 0U, 0U);
+ }
+ ret = pci_get_bus_for_seg(x1, &start_end_bus, &nseg);
+ SMC_RET3(handle, ret, start_end_bus, nseg);
+ break;
+ }
+ default:
+ /* should be unreachable */
+ WARN("Unimplemented PCI Service Call: 0x%x\n", smc_fid);
+ SMC_RET1(handle, SMC_PCI_CALL_NOT_SUPPORTED);
+ }
+}
diff --git a/services/std_svc/std_svc_setup.c b/services/std_svc/std_svc_setup.c
index 540bb86..7f0252d 100644
--- a/services/std_svc/std_svc_setup.c
+++ b/services/std_svc/std_svc_setup.c
@@ -13,6 +13,7 @@
#include <lib/pmf/pmf.h>
#include <lib/psci/psci.h>
#include <lib/runtime_instr.h>
+#include <services/pci_svc.h>
#include <services/sdei.h>
#include <services/spm_mm_svc.h>
#include <services/spmd_svc.h>
@@ -158,6 +159,13 @@
}
#endif
+#if SMC_PCI_SUPPORT
+ if (is_pci_fid(smc_fid)) {
+ return pci_smc_handler(smc_fid, x1, x2, x3, x4, cookie, handle,
+ flags);
+ }
+#endif
+
switch (smc_fid) {
case ARM_STD_SVC_CALL_COUNT:
/*