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Commit da85170d authored by danh-arm's avatar danh-arm
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Merge pull request #289 from danh-arm/vw/tlkd-args-via-cpu-regs-v4 

Pass arguments/results between EL3/S-EL1 via CPU registers (x0-x7) v4
parents 620b5be9 709a3c47
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include/bl32/payloads/tlk.h
View file @ da85170d
......@@ -52,7 +52,6 @@
#define TLK_PREEMPTED (0x32000002 | (1 << 31))
#define TLK_ENTRY_DONE (0x32000003 | (1 << 31))
#define TLK_VA_TRANSLATE (0x32000004 | (1 << 31))
#define TLK_FID_SHARED_MEMBUF (0x32000005 | (1 << 31))
/*
* Trusted Application specific function IDs
......
services/spd/tlkd/tlkd_main.c
View file @ da85170d
......@@ -65,36 +65,6 @@ DEFINE_SVC_UUID(tlk_uuid,
int32_t tlkd_init(void);
/*
* The number of arguments/results to save during a SMC call for TLK.
*/
#define TLK_SHDBUF_SIZE 4
/*******************************************************************************
* Shared memory buffer for passing SMC args/results to TLK
******************************************************************************/
typedef struct tlk_args_results {
uint64_t args[TLK_SHDBUF_SIZE];
} tlk_args_results_t;
static tlk_args_results_t *tlk_args_results_buf;
/*
* Helper function to store args from TLK and pass results back
*/
static inline void store_tlk_args_results(uint64_t x0, uint64_t x1, uint64_t x2,
uint64_t x3)
{
/* store arguments sent by TLK */
tlk_args_results_buf->args[0] = x0;
tlk_args_results_buf->args[1] = x1;
tlk_args_results_buf->args[2] = x2;
tlk_args_results_buf->args[3] = x3;
flush_dcache_range((uint64_t)tlk_args_results_buf,
sizeof(tlk_args_results_t));
}
/*******************************************************************************
* Secure Payload Dispatcher setup. The SPD finds out the SP entrypoint and type
* (aarch32/aarch64) if not already known and initialises the context for entry
......@@ -187,8 +157,9 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
uint64_t flags)
{
cpu_context_t *ns_cpu_context;
gp_regs_t *gp_regs;
uint32_t ns;
uint64_t vaddr, type, par;
uint64_t par;
/* Passing a NULL context is a critical programming error */
assert(handle);
......@@ -226,7 +197,7 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
cm_el1_sysregs_context_restore(NON_SECURE);
cm_set_next_eret_context(NON_SECURE);
SMC_RET1(ns_cpu_context, tlk_args_results_buf->args[0]);
SMC_RET1(ns_cpu_context, x1);
/*
* Request from non secure world to resume the preempted
......@@ -281,7 +252,7 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
case TLK_TA_LAUNCH_OP:
case TLK_TA_SEND_EVENT:
if (!ns || !tlk_args_results_buf)
if (!ns)
SMC_RET1(handle, SMC_UNK);
/*
......@@ -308,41 +279,67 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
*/
set_std_smc_active_flag(tlk_ctx.state);
/* Save args for use by the SP on return */
store_tlk_args_results(smc_fid, x1, x2, x3);
/*
* We are done stashing the non-secure context. Ask the
* secure payload to do the work now.
*/
cm_el1_sysregs_context_restore(SECURE);
cm_set_next_eret_context(SECURE);
SMC_RET0(&tlk_ctx.cpu_ctx);
/*
* TLK is a 32-bit Trusted OS and so expects the SMC
* arguments via r0-r7. TLK expects the monitor frame
* registers to be 64-bits long. Hence, we pass x0 in
* r0-r1, x1 in r2-r3, x3 in r4-r5 and x4 in r6-r7.
*
* As smc_fid is a uint32 value, r1 contains 0.
*/
gp_regs = get_gpregs_ctx(&tlk_ctx.cpu_ctx);
write_ctx_reg(gp_regs, CTX_GPREG_X4, (uint32_t)x2);
write_ctx_reg(gp_regs, CTX_GPREG_X5, (uint32_t)(x2 >> 32));
write_ctx_reg(gp_regs, CTX_GPREG_X6, (uint32_t)x3);
write_ctx_reg(gp_regs, CTX_GPREG_X7, (uint32_t)(x3 >> 32));
SMC_RET4(&tlk_ctx.cpu_ctx, smc_fid, 0, (uint32_t)x1,
(uint32_t)(x1 >> 32));
/*
* Translate NS/EL1-S virtual addresses
* Translate NS/EL1-S virtual addresses.
*
* x1 = virtual address
* x3 = type (NS/S)
*
* Returns PA:lo in r0, PA:hi in r1.
*/
case TLK_VA_TRANSLATE:
if (ns || !tlk_args_results_buf)
/* Should be invoked only by secure world */
if (ns)
SMC_RET1(handle, SMC_UNK);
/* virtual address and type: ns/s */
vaddr = tlk_args_results_buf->args[0];
type = tlk_args_results_buf->args[1];
/* NS virtual addresses are 64-bit long */
if (x3 & TLK_TRANSLATE_NS_VADDR)
x1 = (uint32_t)x1 | (x2 << 32);
par = tlkd_va_translate(vaddr, type);
if (!x1)
SMC_RET1(handle, SMC_UNK);
/*
* TODO: Sanity check x1. This would require platform
* support.
*/
/* Save PA for use by the SP on return */
store_tlk_args_results(par, 0, 0, 0);
/* virtual address and type: ns/s */
par = tlkd_va_translate(x1, x3);
SMC_RET0(handle);
/* return physical address in r0-r1 */
SMC_RET4(handle, (uint32_t)par, (uint32_t)(par >> 32), 0, 0);
/*
* This is a request from the SP to mark completion of
* a standard function ID.
*/
case TLK_REQUEST_DONE:
if (ns || !tlk_args_results_buf)
if (ns)
SMC_RET1(handle, SMC_UNK);
/*
......@@ -366,14 +363,14 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
*/
cm_el1_sysregs_context_restore(NON_SECURE);
cm_set_next_eret_context(NON_SECURE);
SMC_RET1(ns_cpu_context, tlk_args_results_buf->args[0]);
SMC_RET1(ns_cpu_context, x1);
/*
* This function ID is used only by the SP to indicate it has
* finished initialising itself after a cold boot
*/
case TLK_ENTRY_DONE:
if (ns || !tlk_args_results_buf)
if (ns)
SMC_RET1(handle, SMC_UNK);
/*
......@@ -388,23 +385,7 @@ uint64_t tlkd_smc_handler(uint32_t smc_fid,
* into the SP. Jump back to the original C runtime
* context.
*/
tlkd_synchronous_sp_exit(&tlk_ctx, tlk_args_results_buf->args[0]);
/*
* This is a request from the secure payload to register
* shared memory to pass SMC args/results between EL1, EL3.
*/
case TLK_FID_SHARED_MEMBUF:
if (ns || !x1)
SMC_RET1(handle, SMC_UNK);
/*
* TODO: Check if the passed memory pointer is valid. Might
* require a call into the platform code.
*/
tlk_args_results_buf = (tlk_args_results_t *)x1;
SMC_RET0(handle);
tlkd_synchronous_sp_exit(&tlk_ctx, x1);
/*
* Return the number of service function IDs implemented to
......
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