Add runtime services framework
This patch introduces the framework to enable registration and
initialisation of runtime services. PSCI is registered and initialised
as a runtime service. Handling of runtime service requests will be
implemented in subsequent patches.
Change-Id: Id21e7ddc5a33d42b7d6e455b41155fc5441a9547
diff --git a/Makefile b/Makefile
index 1ebc172..83f6813 100644
--- a/Makefile
+++ b/Makefile
@@ -36,8 +36,11 @@
KBUILD_VERBOSE = 0
endif
-CHECKPATCH_ARGS = --no-tree --no-signoff
-CHECKCODE_ARGS = --no-patch --no-tree --no-signoff
+# Checkpatch ignores
+CHECK_IGNORE = --ignore COMPLEX_MACRO
+
+CHECKPATCH_ARGS = --no-tree --no-signoff ${CHECK_IGNORE}
+CHECKCODE_ARGS = --no-patch --no-tree --no-signoff ${CHECK_IGNORE}
ifeq "${KBUILD_VERBOSE}" "0"
Q=@
diff --git a/bl31/bl31.ld.S b/bl31/bl31.ld.S
index 2583c9a..859ccfe 100644
--- a/bl31/bl31.ld.S
+++ b/bl31/bl31.ld.S
@@ -50,6 +50,13 @@
*bl31_entrypoint.o(.text)
*(.text)
*(.rodata*)
+
+ /* Ensure 8-byte alignment for descriptors */
+ . = ALIGN(8);
+ __RT_SVC_DESCS_START__ = .;
+ *(rt_svc_descs)
+ __RT_SVC_DESCS_END__ = .;
+
*(.vectors)
__RO_END_UNALIGNED__ = .;
/*
diff --git a/bl31/bl31_main.c b/bl31/bl31_main.c
index fb69718..dc65b60 100644
--- a/bl31/bl31_main.c
+++ b/bl31/bl31_main.c
@@ -57,7 +57,6 @@
void bl31_main(void)
{
el_change_info *image_info;
- unsigned long mpidr = read_mpidr();
/* Perform remaining generic architectural setup from EL3 */
bl31_arch_setup();
@@ -72,7 +71,7 @@
bl31_lib_init();
/* Initialize the runtime services e.g. psci */
- runtime_svc_init(mpidr);
+ runtime_svc_init();
/* Clean caches before re-entering normal world */
dcsw_op_all(DCCSW);
diff --git a/common/psci/psci_setup.c b/common/psci/psci_setup.c
index 91de1ab..c471d1f 100644
--- a/common/psci/psci_setup.c
+++ b/common/psci/psci_setup.c
@@ -36,6 +36,7 @@
#include <platform.h>
#include <psci_private.h>
#include <context_mgmt.h>
+#include <runtime_svc.h>
/*******************************************************************************
* Per cpu non-secure contexts used to program the architectural state prior
@@ -275,8 +276,9 @@
* level within the 'psci_aff_map' array. This allows restricting search of a
* node at an affinity level between the indices in the limits array.
******************************************************************************/
-void psci_setup(unsigned long mpidr)
+int32_t psci_setup(void)
{
+ unsigned long mpidr = read_mpidr();
int afflvl, affmap_idx, max_afflvl;
aff_map_node *node;
@@ -335,5 +337,16 @@
platform_setup_pm(&psci_plat_pm_ops);
assert(psci_plat_pm_ops);
- return;
+ return 0;
}
+
+/* Register PSCI as a run time service */
+DECLARE_RT_SVC(
+ psci,
+
+ OEN_STD_START,
+ OEN_STD_END,
+ SMC_TYPE_FAST,
+ psci_setup,
+ NULL
+);
diff --git a/common/runtime_svc.c b/common/runtime_svc.c
index 1bda151..c059078 100644
--- a/common/runtime_svc.c
+++ b/common/runtime_svc.c
@@ -39,13 +39,106 @@
#include <bl_common.h>
#include <psci.h>
#include <runtime_svc.h>
+#include <debug.h>
/*******************************************************************************
- * Perform initialization of runtime services possibly across exception levels
- * in the secure address space e.g. psci & interrupt handling.
+ * The 'rt_svc_descs' array holds the runtime service descriptors exported by
+ * services by placing them in the 'rt_svc_descs' linker section.
+ * The 'rt_svc_descs_indices' array holds the index of a descriptor in the
+ * 'rt_svc_descs' array. When an SMC arrives, the OEN[29:24] bits and the call
+ * type[31] bit in the function id are combined to get an index into the
+ * 'rt_svc_descs_indices' array. This gives the index of the descriptor in the
+ * 'rt_svc_descs' array which contains the SMC handler.
******************************************************************************/
-void runtime_svc_init(unsigned long mpidr)
+#define RT_SVC_DESCS_START ((uint64_t) (&__RT_SVC_DESCS_START__))
+#define RT_SVC_DESCS_END ((uint64_t) (&__RT_SVC_DESCS_END__))
+uint8_t rt_svc_descs_indices[MAX_RT_SVCS];
+static rt_svc_desc *rt_svc_descs;
+
+/*******************************************************************************
+ * Simple routine to sanity check a runtime service descriptor before using it
+ ******************************************************************************/
+static int32_t validate_rt_svc_desc(rt_svc_desc *desc)
{
- psci_setup(mpidr);
+ if (desc == NULL)
+ return -EINVAL;
+
+ if (desc->start_oen > desc->end_oen)
+ return -EINVAL;
+
+ if (desc->end_oen >= OEN_LIMIT)
+ return -EINVAL;
+
+ if (desc->call_type != SMC_TYPE_FAST && desc->call_type != SMC_TYPE_STD)
+ return -EINVAL;
+
+ /* A runtime service having no init or handle function doesn't make sense */
+ if (desc->init == NULL && desc->handle == NULL)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*******************************************************************************
+ * This function calls the initialisation routine in the descriptor exported by
+ * a runtime service. Once a descriptor has been validated, its start & end
+ * owning entity numbers and the call type are combined to form a unique oen.
+ * The unique oen is used as an index into the 'rt_svc_descs_indices' array.
+ * The index of the runtime service descriptor is stored at this index.
+ ******************************************************************************/
+void runtime_svc_init()
+{
+ int32_t rc = 0;
+ uint32_t index, start_idx, end_idx;
+ uint64_t rt_svc_descs_num;
+
+ /* If no runtime services are implemented then simply bail out */
+ rt_svc_descs_num = RT_SVC_DESCS_END - RT_SVC_DESCS_START;
+ rt_svc_descs_num /= sizeof(rt_svc_desc);
+ if (rt_svc_descs_num == 0)
+ return;
+
+ /* Initialise internal variables to invalid state */
+ memset(rt_svc_descs_indices, -1, sizeof(rt_svc_descs_indices));
+
+ rt_svc_descs = (rt_svc_desc *) RT_SVC_DESCS_START;
+ for (index = 0; index < rt_svc_descs_num; index++) {
+
+ /*
+ * An invalid descriptor is an error condition since it is
+ * difficult to predict the system behaviour in the absence
+ * of this service.
+ */
+ rc = validate_rt_svc_desc(&rt_svc_descs[index]);
+ if (rc) {
+ ERROR("Invalid runtime service descriptor 0x%x (%s)\n",
+ &rt_svc_descs[index],
+ rt_svc_descs[index].name);
+ goto error;
+ }
+
+ /*
+ * Fill the indices corresponding to the start and end owning
+ * entity numbers with the index of the descriptor which will
+ * handle the SMCs for this owning entity range.
+ */
+ start_idx = get_unique_oen(rt_svc_descs[index].start_oen,
+ rt_svc_descs[index].call_type);
+ end_idx = get_unique_oen(rt_svc_descs[index].end_oen,
+ rt_svc_descs[index].call_type);
+ for (; start_idx <= end_idx; start_idx++)
+ rt_svc_descs_indices[start_idx] = index;
+
+ /* Call the initialisation routine for this runtime service */
+ rc = rt_svc_descs[index].init();
+ if (rc) {
+ ERROR("Error initializing runtime service %s\n",
+ rt_svc_descs[index].name);
+ goto error;
+ }
+ }
+
return;
+error:
+ panic();
}
diff --git a/include/psci.h b/include/psci.h
index 5da78ee..e14c60b 100644
--- a/include/psci.h
+++ b/include/psci.h
@@ -156,7 +156,6 @@
unsigned long);
extern void psci_aff_on_finish_entry(void);
extern void psci_aff_suspend_finish_entry(void);
-extern void psci_setup(unsigned long);
#endif /*__ASSEMBLY__*/
diff --git a/include/runtime_svc.h b/include/runtime_svc.h
index e5bfcf3..db8fd29 100644
--- a/include/runtime_svc.h
+++ b/include/runtime_svc.h
@@ -38,20 +38,47 @@
******************************************************************************/
#define FUNCID_TYPE_SHIFT 31
#define FUNCID_CC_SHIFT 30
-#define FUNCID_OWNER_SHIFT 24
+#define FUNCID_OEN_SHIFT 24
#define FUNCID_NUM_SHIFT 0
#define FUNCID_TYPE_MASK 0x1
#define FUNCID_CC_MASK 0x1
-#define FUNCID_OWNER_MASK 0x3f
+#define FUNCID_OEN_MASK 0x3f
#define FUNCID_NUM_MASK 0xffff
+#define FUNCID_TYPE_WIDTH 1
+#define FUNCID_CC_WIDTH 1
+#define FUNCID_OEN_WIDTH 6
+#define FUNCID_NUM_WIDTH 16
+
#define GET_SMC_CC(id) ((id >> FUNCID_CC_SHIFT) & \
FUNCID_CC_MASK)
#define SMC_64 1
#define SMC_32 0
#define SMC_UNK 0xffffffff
+#define SMC_TYPE_FAST 1
+#define SMC_TYPE_STD 0
+
+/*******************************************************************************
+ * Owning entity number definitions inside the function id as per the SMC
+ * calling convention
+ ******************************************************************************/
+#define OEN_ARM_START 0
+#define OEN_ARM_END 0
+#define OEN_CPU_START 1
+#define OEN_CPU_END 1
+#define OEN_SIP_START 2
+#define OEN_SIP_END 2
+#define OEN_OEM_START 3
+#define OEN_OEM_END 3
+#define OEN_STD_START 4 /* Standard Calls */
+#define OEN_STD_END 4
+#define OEN_TAP_START 48 /* Trusted Applications */
+#define OEN_TAP_END 49
+#define OEN_TOS_START 50 /* Trusted OS */
+#define OEN_TOS_END 63
+#define OEN_LIMIT 64
/*******************************************************************************
* Constants to indicate type of exception to the common exception handler.
@@ -112,8 +139,77 @@
#define GPREGS_FP_OFF 0x100
#define GPREGS_LR_OFF 0x108
+/*
+ * Constants to allow the assembler access a runtime service
+ * descriptor
+ */
+#define SIZEOF_RT_SVC_DESC 32
+#define RT_SVC_DESC_INIT 16
+#define RT_SVC_DESC_HANDLE 24
+
+/*
+ * The function identifier has 6 bits for the owning entity number and
+ * single bit for the type of smc call. When taken together these
+ * values limit the maximum number of runtime services to 128.
+ */
+#define MAX_RT_SVCS 128
+
#ifndef __ASSEMBLY__
+/* Prototype for runtime service initializing function */
+typedef int32_t (*rt_svc_init)(void);
+
+/* Convenience macros to return from SMC handler */
+#define SMC_RET1(_h, _x0) { \
+ write_ctx_reg(get_gpregs_ctx(_h), CTX_GPREG_X0, (_x0)); \
+ return _x0; \
+}
+#define SMC_RET2(_h, _x0, _x1) { \
+ write_ctx_reg(get_gpregs_ctx(_h), CTX_GPREG_X1, (_x1)); \
+ SMC_RET1(_h, (_x0)); \
+}
+#define SMC_RET3(_h, _x0, _x1, _x2) { \
+ write_ctx_reg(get_gpregs_ctx(_h), CTX_GPREG_X2, (_x2)); \
+ SMC_RET2(_h, (_x0), (_x1)); \
+}
+#define SMC_RET4(_h, _x0, _x1, _x2, _x3) { \
+ write_ctx_reg(get_gpregs_ctx(_h), CTX_GPREG_X3, (_x3)); \
+ SMC_RET3(_h, (_x0), (_x1), (_x2)); \
+}
+
+
+/*
+ * Convenience macros to access general purpose registers using handle provided
+ * to SMC handler. These takes the offset values defined in context.h
+ */
+#define SMC_GET_GP(_h, _g) \
+ read_ctx_reg(get_gpregs_ctx(_h), (_g));
+#define SMC_SET_GP(_h, _g, _v) \
+ write_ctx_reg(get_gpregs_ctx(_h), (_g), (_v));
+
+/*
+ * Convenience macros to access EL3 context registers using handle provided to
+ * SMC handler. These takes the offset values defined in context.h
+ */
+#define SMC_GET_EL3(_h, _e) \
+ read_ctx_reg(get_el3state_ctx(_h), (_e));
+#define SMC_SET_EL3(_h, _e, _v) \
+ write_ctx_reg(get_el3state_ctx(_h), (_e), (_v));
+
+/*
+ * Prototype for runtime service SMC handler function. x0 (SMC Function ID) to
+ * x4 are as passed by the caller. Rest of the arguments to SMC and the context
+ * can be accessed using the handle pointer. The cookie parameter is reserved
+ * for future use
+ */
+typedef uint64_t (*rt_svc_handle)(uint32_t smc_fid,
+ uint64_t x1,
+ uint64_t x2,
+ uint64_t x3,
+ uint64_t x4,
+ void *cookie,
+ void *handle,
+ uint64_t flags);
typedef struct {
uint64_t x0;
uint64_t x1;
@@ -150,9 +246,31 @@
* Alignment constraint which allows save & restore of fp & lr on the
* stack during exception handling
*/
- uint64_t fp __attribute__((__aligned__(16)));
+ uint64_t fp __aligned(16);
uint64_t lr;
-} __attribute__((__aligned__(16))) gp_regs;
+} __aligned(16) gp_regs;
+
+typedef struct {
+ uint8_t start_oen;
+ uint8_t end_oen;
+ uint8_t call_type;
+ const char *name;
+ rt_svc_init init;
+ rt_svc_handle handle;
+} rt_svc_desc;
+
+/*
+ * Convenience macro to declare a service descriptor
+ */
+#define DECLARE_RT_SVC(_name, _start, _end, _type, _setup, _smch) \
+ static const rt_svc_desc __svc_desc_ ## _name \
+ __attribute__ ((section("rt_svc_descs"), used)) = { \
+ _start, \
+ _end, \
+ _type, \
+ #_name, \
+ _setup, \
+ _smch }
/*******************************************************************************
* Compile time assertions to ensure that:
@@ -164,11 +282,39 @@
CASSERT((sizeof(gp_regs) == SIZEOF_GPREGS), assert_sizeof_gpregs_mismatch);
CASSERT(GPREGS_FP_OFF == __builtin_offsetof(gp_regs, fp), \
assert_gpregs_fp_offset_mismatch);
+/*
+ * Compile time assertions related to the 'rt_svc_desc' structure to:
+ * 1. ensure that the assembler and the compiler view of the size
+ * of the structure are the same.
+ * 2. ensure that the assembler and the compiler see the initialisation
+ * routine at the same offset.
+ * 2. ensure that the assembler and the compiler see the handler
+ * routine at the same offset.
+ */
+CASSERT((sizeof(rt_svc_desc) == SIZEOF_RT_SVC_DESC), \
+ assert_sizeof_rt_svc_desc_mismatch);
+CASSERT(RT_SVC_DESC_INIT == __builtin_offsetof(rt_svc_desc, init), \
+ assert_rt_svc_desc_init_offset_mismatch);
+CASSERT(RT_SVC_DESC_HANDLE == __builtin_offsetof(rt_svc_desc, handle), \
+ assert_rt_svc_desc_handle_offset_mismatch);
+
+
+/*
+ * This macro combines the call type and the owning entity number corresponding
+ * to a runtime service to generate a unique owning entity number. This unique
+ * oen is used to access an entry in the 'rt_svc_descs_indices' array. The entry
+ * contains the index of the service descriptor in the 'rt_svc_descs' array.
+ */
+#define get_unique_oen(oen, call_type) ((oen & FUNCID_OEN_MASK) | \
+ ((call_type & FUNCID_TYPE_MASK) \
+ << FUNCID_OEN_WIDTH))
/*******************************************************************************
* Function & variable prototypes
******************************************************************************/
-extern void runtime_svc_init(unsigned long mpidr);
+extern void runtime_svc_init();
+extern uint64_t __RT_SVC_DESCS_START__;
+extern uint64_t __RT_SVC_DESCS_END__;
#endif /*__ASSEMBLY__*/
#endif /* __RUNTIME_SVC_H__ */