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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-05 13:51:19 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-05 13:51:19 -0700 |
commit | dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe (patch) | |
tree | 0a4f3a07e2286918298e635186e42726f4658cbd /arch/arm/mach-qcom/scm.c | |
parent | 9f800363bb0ea459e15bef0928a72c88d374e489 (diff) | |
parent | 8f881c67368f82d0e20e1072b50b21132cc2440d (diff) | |
download | linux-dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe.tar.gz linux-dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe.tar.bz2 linux-dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe.zip |
Merge tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Arnd Bergmann:
"These cleanup patches are mainly move stuff around and should all be
harmless. They are mainly split out so that other branches can be
based on top to avoid conflicts.
Notable changes are:
- We finally remove all mach/timex.h, after CLOCK_TICK_RATE is no
longer used (Uwe Kleine-König)
- The Qualcomm MSM platform is split out into legacy mach-msm and
new-style mach-qcom, to allow easier maintainance of the new
hardware support without regressions (Kumar Gala)
- A rework of some of the Kconfig logic to simplify multiplatform
support (Rob Herring)
- Samsung Exynos gets closer to supporting multiplatform (Sachin
Kamat and others)
- mach-bcm3528 gets merged into mach-bcm (Stephen Warren)
- at91 gains some common clock framework support (Alexandre Belloni,
Jean-Jacques Hiblot and other French people)"
* tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (89 commits)
ARM: hisi: select HAVE_ARM_SCU only for SMP
ARM: efm32: allow uncompress debug output
ARM: prima2: build reset code standalone
ARM: at91: add PWM clock
ARM: at91: move sam9261 SoC to common clk
ARM: at91: prepare common clk transition for sam9261 SoC
ARM: at91: updated the at91_dt_defconfig with support for the ADS7846
ARM: at91: dt: sam9261: Device Tree support for the at91sam9261ek
ARM: at91: dt: defconfig: Added the sam9261 to the list of DT-enabled SOCs
ARM: at91: dt: Add at91sam9261 dt SoC support
ARM: at91: switch sam9rl to common clock framework
ARM: at91/dt: define main clk frequency of at91sam9rlek
ARM: at91/dt: define at91sam9rl clocks
ARM: at91: prepare common clk transition for sam9rl SoCs
ARM: at91: prepare sam9 dt boards transition to common clk
ARM: at91: dt: sam9rl: Device Tree for the at91sam9rlek
ARM: at91/defconfig: Add the sam9rl to the list of DT-enabled SOCs
ARM: at91: Add at91sam9rl DT SoC support
ARM: at91: prepare at91sam9rl DT transition
ARM: at91/defconfig: refresh at91sam9260_9g20_defconfig
...
Diffstat (limited to 'arch/arm/mach-qcom/scm.c')
-rw-r--r-- | arch/arm/mach-qcom/scm.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/arch/arm/mach-qcom/scm.c b/arch/arm/mach-qcom/scm.c new file mode 100644 index 000000000000..c536fd6bf827 --- /dev/null +++ b/arch/arm/mach-qcom/scm.c @@ -0,0 +1,299 @@ +/* Copyright (c) 2010, Code Aurora Forum. 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 + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/errno.h> +#include <linux/err.h> + +#include <asm/cacheflush.h> + +#include "scm.h" + +/* Cache line size for msm8x60 */ +#define CACHELINESIZE 32 + +#define SCM_ENOMEM -5 +#define SCM_EOPNOTSUPP -4 +#define SCM_EINVAL_ADDR -3 +#define SCM_EINVAL_ARG -2 +#define SCM_ERROR -1 +#define SCM_INTERRUPTED 1 + +static DEFINE_MUTEX(scm_lock); + +/** + * struct scm_command - one SCM command buffer + * @len: total available memory for command and response + * @buf_offset: start of command buffer + * @resp_hdr_offset: start of response buffer + * @id: command to be executed + * @buf: buffer returned from scm_get_command_buffer() + * + * An SCM command is laid out in memory as follows: + * + * ------------------- <--- struct scm_command + * | command header | + * ------------------- <--- scm_get_command_buffer() + * | command buffer | + * ------------------- <--- struct scm_response and + * | response header | scm_command_to_response() + * ------------------- <--- scm_get_response_buffer() + * | response buffer | + * ------------------- + * + * There can be arbitrary padding between the headers and buffers so + * you should always use the appropriate scm_get_*_buffer() routines + * to access the buffers in a safe manner. + */ +struct scm_command { + u32 len; + u32 buf_offset; + u32 resp_hdr_offset; + u32 id; + u32 buf[0]; +}; + +/** + * struct scm_response - one SCM response buffer + * @len: total available memory for response + * @buf_offset: start of response data relative to start of scm_response + * @is_complete: indicates if the command has finished processing + */ +struct scm_response { + u32 len; + u32 buf_offset; + u32 is_complete; +}; + +/** + * alloc_scm_command() - Allocate an SCM command + * @cmd_size: size of the command buffer + * @resp_size: size of the response buffer + * + * Allocate an SCM command, including enough room for the command + * and response headers as well as the command and response buffers. + * + * Returns a valid &scm_command on success or %NULL if the allocation fails. + */ +static struct scm_command *alloc_scm_command(size_t cmd_size, size_t resp_size) +{ + struct scm_command *cmd; + size_t len = sizeof(*cmd) + sizeof(struct scm_response) + cmd_size + + resp_size; + + cmd = kzalloc(PAGE_ALIGN(len), GFP_KERNEL); + if (cmd) { + cmd->len = len; + cmd->buf_offset = offsetof(struct scm_command, buf); + cmd->resp_hdr_offset = cmd->buf_offset + cmd_size; + } + return cmd; +} + +/** + * free_scm_command() - Free an SCM command + * @cmd: command to free + * + * Free an SCM command. + */ +static inline void free_scm_command(struct scm_command *cmd) +{ + kfree(cmd); +} + +/** + * scm_command_to_response() - Get a pointer to a scm_response + * @cmd: command + * + * Returns a pointer to a response for a command. + */ +static inline struct scm_response *scm_command_to_response( + const struct scm_command *cmd) +{ + return (void *)cmd + cmd->resp_hdr_offset; +} + +/** + * scm_get_command_buffer() - Get a pointer to a command buffer + * @cmd: command + * + * Returns a pointer to the command buffer of a command. + */ +static inline void *scm_get_command_buffer(const struct scm_command *cmd) +{ + return (void *)cmd->buf; +} + +/** + * scm_get_response_buffer() - Get a pointer to a response buffer + * @rsp: response + * + * Returns a pointer to a response buffer of a response. + */ +static inline void *scm_get_response_buffer(const struct scm_response *rsp) +{ + return (void *)rsp + rsp->buf_offset; +} + +static int scm_remap_error(int err) +{ + switch (err) { + case SCM_ERROR: + return -EIO; + case SCM_EINVAL_ADDR: + case SCM_EINVAL_ARG: + return -EINVAL; + case SCM_EOPNOTSUPP: + return -EOPNOTSUPP; + case SCM_ENOMEM: + return -ENOMEM; + } + return -EINVAL; +} + +static u32 smc(u32 cmd_addr) +{ + int context_id; + register u32 r0 asm("r0") = 1; + register u32 r1 asm("r1") = (u32)&context_id; + register u32 r2 asm("r2") = cmd_addr; + do { + 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"); + } while (r0 == SCM_INTERRUPTED); + + return r0; +} + +static int __scm_call(const struct scm_command *cmd) +{ + int ret; + u32 cmd_addr = virt_to_phys(cmd); + + /* + * Flush the entire cache here so callers don't have to remember + * to flush the cache when passing physical addresses to the secure + * side in the buffer. + */ + flush_cache_all(); + ret = smc(cmd_addr); + if (ret < 0) + ret = scm_remap_error(ret); + + return ret; +} + +/** + * scm_call() - Send an SCM command + * @svc_id: service identifier + * @cmd_id: command identifier + * @cmd_buf: command buffer + * @cmd_len: length of the command buffer + * @resp_buf: response buffer + * @resp_len: length of the response buffer + * + * Sends a command to the SCM and waits for the command to finish processing. + */ +int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len, + void *resp_buf, size_t resp_len) +{ + int ret; + struct scm_command *cmd; + struct scm_response *rsp; + + cmd = alloc_scm_command(cmd_len, resp_len); + if (!cmd) + return -ENOMEM; + + cmd->id = (svc_id << 10) | cmd_id; + if (cmd_buf) + memcpy(scm_get_command_buffer(cmd), cmd_buf, cmd_len); + + mutex_lock(&scm_lock); + ret = __scm_call(cmd); + mutex_unlock(&scm_lock); + if (ret) + goto out; + + rsp = scm_command_to_response(cmd); + do { + u32 start = (u32)rsp; + u32 end = (u32)scm_get_response_buffer(rsp) + resp_len; + start &= ~(CACHELINESIZE - 1); + while (start < end) { + asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start) + : "memory"); + start += CACHELINESIZE; + } + } while (!rsp->is_complete); + + if (resp_buf) + memcpy(resp_buf, scm_get_response_buffer(rsp), resp_len); +out: + free_scm_command(cmd); + return ret; +} +EXPORT_SYMBOL(scm_call); + +u32 scm_get_version(void) +{ + int context_id; + static u32 version = -1; + register u32 r0 asm("r0"); + register u32 r1 asm("r1"); + + if (version != -1) + return version; + + mutex_lock(&scm_lock); + + r0 = 0x1 << 8; + r1 = (u32)&context_id; + do { + asm volatile( + __asmeq("%0", "r0") + __asmeq("%1", "r1") + __asmeq("%2", "r0") + __asmeq("%3", "r1") +#ifdef REQUIRES_SEC + ".arch_extension sec\n" +#endif + "smc #0 @ switch to secure world\n" + : "=r" (r0), "=r" (r1) + : "r" (r0), "r" (r1) + : "r2", "r3"); + } while (r0 == SCM_INTERRUPTED); + + version = r1; + mutex_unlock(&scm_lock); + + return version; +} +EXPORT_SYMBOL(scm_get_version); |