[PATCH v2 03/11] firmware: qcom: scm: switch to using the SCM allocator

Bartosz Golaszewski
2023-09-28T09:21:35Z

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

We need to allocate, map and pass a buffer to the trustzone if we have
more than 4 arguments for a given SCM calls. Let's use the new SCM
allocator for that memory and shrink the code in process.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
drivers/firmware/qcom/qcom_scm-smc.c | 21 ++++-----------------
1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/firmware/qcom/qcom_scm-smc.c b/drivers/firmware/qcom/qcom_scm-smc.c
index 16cf88acfa8e..0d5554df1321 100644
--- a/drivers/firmware/qcom/qcom_scm-smc.c
+++ b/drivers/firmware/qcom/qcom_scm-smc.c
@@ -2,6 +2,7 @@
/* Copyright (c) 2015,2019 The Linux Foundation. All rights reserved.
*/

+#include <linux/cleanup.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/delay.h>
@@ -152,8 +153,7 @@ int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
{
int arglen = desc->arginfo & 0xf;
int i, ret;
- dma_addr_t args_phys = 0;
- void *args_virt = NULL;
+ void *args_virt __free(qcom_scm_mem) = NULL;
size_t alloc_len;
gfp_t flag = atomic ? GFP_ATOMIC : GFP_KERNEL;
u32 smccc_call_type = atomic ? ARM_SMCCC_FAST_CALL : ARM_SMCCC_STD_CALL;
@@ -173,7 +173,7 @@ int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,

if (unlikely(arglen > SCM_SMC_N_REG_ARGS)) {
alloc_len = SCM_SMC_N_EXT_ARGS * sizeof(u64);
- args_virt = kzalloc(PAGE_ALIGN(alloc_len), flag);
+ args_virt = qcom_scm_mem_alloc(PAGE_ALIGN(alloc_len), flag);

if (!args_virt)
return -ENOMEM;
@@ -192,25 +192,12 @@ int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
SCM_SMC_FIRST_EXT_IDX]);
}

- args_phys = dma_map_single(dev, args_virt, alloc_len,
- DMA_TO_DEVICE);
-
- if (dma_mapping_error(dev, args_phys)) {
- kfree(args_virt);
- return -ENOMEM;
- }
-
- smc.args[SCM_SMC_LAST_REG_IDX] = args_phys;
+ smc.args[SCM_SMC_LAST_REG_IDX] = qcom_scm_mem_to_phys(args_virt);
}

/* ret error check follows after args_virt cleanup*/
ret = __scm_smc_do(dev, &smc, &smc_res, atomic);

- if (args_virt) {
- dma_unmap_single(dev, args_phys, alloc_len, DMA_TO_DEVICE);
- kfree(args_virt);
- }
-
if (ret)
return ret;

--
2.39.2