Re: [Patch v2 1/5] firmware: qcom_scm: Introduce SCM calls to access LMh

From: Thara Gopinath
Date: Fri Jun 25 2021 - 11:45:50 EST




On 6/24/21 1:48 PM, Matthias Kaehlcke wrote:
On Thu, Jun 24, 2021 at 07:58:09AM -0400, Thara Gopinath wrote:
Introduce SCM calls to access/configure limits management hardware(LMH).

Signed-off-by: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
---

v1->v2:
Changed the input parameters in qcom_scm_lmh_dcvsh from payload_buf and
payload_size to payload_fn, payload_reg, payload_val as per Bjorn's review
comments.

drivers/firmware/qcom_scm.c | 54 +++++++++++++++++++++++++++++++++++++
drivers/firmware/qcom_scm.h | 4 +++
include/linux/qcom_scm.h | 14 ++++++++++
3 files changed, 72 insertions(+)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index ee9cb545e73b..19e9fb91d084 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -1147,6 +1147,60 @@ int qcom_scm_qsmmu500_wait_safe_toggle(bool en)
}
EXPORT_SYMBOL(qcom_scm_qsmmu500_wait_safe_toggle);
+bool qcom_scm_lmh_dcvsh_available(void)
+{
+ return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_LMH, QCOM_SCM_LMH_LIMIT_DCVSH);
+}
+EXPORT_SYMBOL(qcom_scm_lmh_dcvsh_available);
+
+int qcom_scm_lmh_profile_change(u32 profile_id)
+{
+ struct qcom_scm_desc desc = {
+ .svc = QCOM_SCM_SVC_LMH,
+ .cmd = QCOM_SCM_LMH_LIMIT_PROFILE_CHANGE,
+ .arginfo = QCOM_SCM_ARGS(1, QCOM_SCM_VAL),
+ .args[0] = profile_id,
+ .owner = ARM_SMCCC_OWNER_SIP,
+ };
+
+ return qcom_scm_call(__scm->dev, &desc, NULL);
+}
+EXPORT_SYMBOL(qcom_scm_lmh_profile_change);
+
+int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
+ u64 limit_node, u32 node_id, u64 version)
+{
+ dma_addr_t payload_phys;
+ u32 *payload_buf;
+ int payload_size = 5 * sizeof(u32);
+
+ struct qcom_scm_desc desc = {
+ .svc = QCOM_SCM_SVC_LMH,
+ .cmd = QCOM_SCM_LMH_LIMIT_DCVSH,
+ .arginfo = QCOM_SCM_ARGS(5, QCOM_SCM_RO, QCOM_SCM_VAL, QCOM_SCM_VAL,
+ QCOM_SCM_VAL, QCOM_SCM_VAL),
+ .args[1] = payload_size,
+ .args[2] = limit_node,
+ .args[3] = node_id,
+ .args[4] = version,
+ .owner = ARM_SMCCC_OWNER_SIP,
+ };
+
+ payload_buf = dma_alloc_coherent(__scm->dev, payload_size, &payload_phys, GFP_KERNEL);
+ if (!payload_buf)
+ return -ENOMEM;
+
+ payload_buf[0] = payload_fn;
+ payload_buf[1] = 0;
+ payload_buf[2] = payload_reg;
+ payload_buf[3] = 1;
+ payload_buf[4] = payload_val;
+
+ desc.args[0] = payload_phys;
+ return qcom_scm_call(__scm->dev, &desc, NULL);

dma_free_coherent()?

yep.. A free should be done here. Will fix it



--
Warm Regards
Thara (She/Her/Hers)