| Message ID | 1687955688-20809-18-git-send-email-quic_mojha@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4,01/21] docs: qcom: Add qualcomm minidump guide | expand |
On Wed, Jun 28, 2023 at 06:04:44PM +0530, Mukesh Ojha wrote: > It was realized by Srinivas K. that there is a need of > read-modify-write scm exported function so that it can > be used by multiple clients. > > Let's introduce qcom_scm_io_update_field() which masks > out the bits and write the passed value to that > bit-offset. Subsequent patch will use this function. > > Suggested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> > Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com> > --- > drivers/firmware/qcom_scm.c | 15 +++++++++++++++ > include/linux/firmware/qcom/qcom_scm.h | 2 ++ > 2 files changed, 17 insertions(+) > > diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c > index fde33acd46b7..104d86e49b97 100644 > --- a/drivers/firmware/qcom_scm.c > +++ b/drivers/firmware/qcom_scm.c > @@ -407,6 +407,21 @@ int qcom_scm_set_remote_state(u32 state, u32 id) > } > EXPORT_SYMBOL(qcom_scm_set_remote_state); > > +int qcom_scm_io_update_field(phys_addr_t addr, unsigned int mask, unsigned int val) > +{ > + unsigned int old, new; > + int ret; > + > + ret = qcom_scm_io_readl(addr, &old); > + if (ret) > + return ret; > + > + new = (old & ~mask) | (val & mask); > + > + return qcom_scm_io_writel(addr, new); > +} I believe this API leaves the atomicity part to the client. or how does it work? Thanks, Pavan
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c index fde33acd46b7..104d86e49b97 100644 --- a/drivers/firmware/qcom_scm.c +++ b/drivers/firmware/qcom_scm.c @@ -407,6 +407,21 @@ int qcom_scm_set_remote_state(u32 state, u32 id) } EXPORT_SYMBOL(qcom_scm_set_remote_state); +int qcom_scm_io_update_field(phys_addr_t addr, unsigned int mask, unsigned int val) +{ + unsigned int old, new; + int ret; + + ret = qcom_scm_io_readl(addr, &old); + if (ret) + return ret; + + new = (old & ~mask) | (val & mask); + + return qcom_scm_io_writel(addr, new); +} +EXPORT_SYMBOL(qcom_scm_io_update_field); + static int __qcom_scm_set_dload_mode(struct device *dev, bool enable) { struct qcom_scm_desc desc = { diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h index 250ea4efb7cb..ca41e4eb33ad 100644 --- a/include/linux/firmware/qcom/qcom_scm.h +++ b/include/linux/firmware/qcom/qcom_scm.h @@ -84,6 +84,8 @@ extern bool qcom_scm_pas_supported(u32 peripheral); extern int qcom_scm_io_readl(phys_addr_t addr, unsigned int *val); extern int qcom_scm_io_writel(phys_addr_t addr, unsigned int val); +extern int qcom_scm_io_update_field(phys_addr_t addr, unsigned int mask, + unsigned int val); extern bool qcom_scm_restore_sec_cfg_available(void); extern int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare);
It was realized by Srinivas K. that there is a need of read-modify-write scm exported function so that it can be used by multiple clients. Let's introduce qcom_scm_io_update_field() which masks out the bits and write the passed value to that bit-offset. Subsequent patch will use this function. Suggested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com> --- drivers/firmware/qcom_scm.c | 15 +++++++++++++++ include/linux/firmware/qcom/qcom_scm.h | 2 ++ 2 files changed, 17 insertions(+)