diff options
| author | Stephen Boyd <sboyd@codeaurora.org> | 2015-01-20 20:05:03 +0800 |
|---|---|---|
| committer | Andy Green <andy.green@linaro.org> | 2015-01-20 20:05:03 +0800 |
| commit | 07edb83ce60e8b009c276291869239f9ad8bc452 (patch) | |
| tree | 0c3b2f245c767eebdcd30f621b469e8cb37d3435 | |
| parent | 66cc4a69902f2b4d273e016f2ed14b373386ed4c (diff) | |
soc: qcom: scm: Add atomic SCM APIs
The atomic SCM APIs are useful for commands that are guaranteed by the
secure side to be uninterruptable, atomic and SMP safe. The calling
convention use registers for passing parameters and return values between
the secure and non-secure side. Support this interface with
scm_call_atomic[1-2]() functions corresponding to the number of arguments
passed.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
| -rw-r--r-- | drivers/soc/qcom/scm.c | 73 | ||||
| -rw-r--r-- | include/soc/qcom/scm.h | 5 |
2 files changed, 77 insertions, 1 deletions
diff --git a/drivers/soc/qcom/scm.c b/drivers/soc/qcom/scm.c index 85ea7f1f2b31..2e98d80e2387 100644 --- a/drivers/soc/qcom/scm.c +++ b/drivers/soc/qcom/scm.c @@ -288,6 +288,79 @@ out: } EXPORT_SYMBOL(scm_call); +#define SCM_CLASS_REGISTER (0x2 << 8) +#define SCM_MASK_IRQS BIT(5) +#define SCM_ATOMIC(svc, cmd, n) (((((svc) << 10)|((cmd) & 0x3ff)) << 12) | \ + SCM_CLASS_REGISTER | \ + SCM_MASK_IRQS | \ + (n & 0xf)) + +/** + * scm_call_atomic1() - Send an atomic SCM command with one argument + * @svc_id: service identifier + * @cmd_id: command identifier + * @arg1: first argument + * + * This shall only be used with commands that are guaranteed to be + * uninterruptable, atomic and SMP safe. + */ +s32 scm_call_atomic1(u32 svc, u32 cmd, u32 arg1) +{ + int context_id; + register u32 r0 asm("r0") = SCM_ATOMIC(svc, cmd, 1); + register u32 r1 asm("r1") = (u32)&context_id; + register u32 r2 asm("r2") = arg1; + + asm volatile( + __asmeq("%0", "r0") + __asmeq("%1", "r0") + __asmeq("%2", "r1") + __asmeq("%3", "r2") +#ifdef REQUIRES_SEC + ".arch_extension sec\n" +#endif + "smc #0 @ switch to secure world\n" + : "=r" (r0) + : "r" (r0), "r" (r1), "r" (r2) + : "r3"); + return r0; +} +EXPORT_SYMBOL(scm_call_atomic1); + +/** + * scm_call_atomic2() - Send an atomic SCM command with two arguments + * @svc_id: service identifier + * @cmd_id: command identifier + * @arg1: first argument + * @arg2: second argument + * + * This shall only be used with commands that are guaranteed to be + * uninterruptable, atomic and SMP safe. + */ +s32 scm_call_atomic2(u32 svc, u32 cmd, u32 arg1, u32 arg2) +{ + int context_id; + register u32 r0 asm("r0") = SCM_ATOMIC(svc, cmd, 2); + register u32 r1 asm("r1") = (u32)&context_id; + register u32 r2 asm("r2") = arg1; + register u32 r3 asm("r3") = arg2; + + asm volatile( + __asmeq("%0", "r0") + __asmeq("%1", "r0") + __asmeq("%2", "r1") + __asmeq("%3", "r2") + __asmeq("%4", "r3") +#ifdef REQUIRES_SEC + ".arch_extension sec\n" +#endif + "smc #0 @ switch to secure world\n" + : "=r" (r0) + : "r" (r0), "r" (r1), "r" (r2), "r" (r3)); + return r0; +} +EXPORT_SYMBOL(scm_call_atomic2); + u32 scm_get_version(void) { int context_id; diff --git a/include/soc/qcom/scm.h b/include/soc/qcom/scm.h index dcb4098802c0..a001ef865623 100644 --- a/include/soc/qcom/scm.h +++ b/include/soc/qcom/scm.h @@ -1,4 +1,4 @@ -/* Copyright (c) 2010, Code Aurora Forum. All rights reserved. +/* Copyright (c) 2010-2014, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and @@ -19,6 +19,9 @@ extern int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len, void *resp_buf, size_t resp_len); +extern s32 scm_call_atomic1(u32 svc, u32 cmd, u32 arg1); +extern s32 scm_call_atomic2(u32 svc, u32 cmd, u32 arg1, u32 arg2); + #define SCM_VERSION(major, minor) (((major) << 16) | ((minor) & 0xFF)) extern u32 scm_get_version(void); |