Re: [PATCH v4 19/21] firmware: scm: Modify only the download bits in TCSR register

[Mukesh Ojha]

On 6/28/2023 8:50 PM, Konrad Dybcio wrote:
> On 28.06.2023 14:34, Mukesh Ojha wrote:
> > CrashDump collection is based on the DLOAD bit of TCSR register.
> > To retain other bits, we read the register and modify only the
> > DLOAD bit as the other bits have their own significance.
> >
> > Co-developed-by: Poovendhan Selvaraj <quic_poovendh@xxxxxxxxxxx>
> > Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
> > ---
> >   drivers/firmware/qcom_scm.c | 12 ++++++++++--
> >   1 file changed, 10 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
> > index 104d86e49b97..a9ff77d16c42 100644
> > --- a/drivers/firmware/qcom_scm.c
> > +++ b/drivers/firmware/qcom_scm.c
> > @@ -30,6 +30,11 @@ module_param(download_mode, bool, 0);
> >   #define SCM_HAS_IFACE_CLK	BIT(1)
> >   #define SCM_HAS_BUS_CLK		BIT(2)
> >   
> > +#define QCOM_DOWNLOAD_FULLDUMP		 0x1
> > +#define QCOM_DOWNLOAD_NODUMP		 0x0
> > +#define QCOM_DOWNLOAD_MODE_SHIFT	   4
> > +#define QCOM_DOWNLOAD_MODE_MASK		0x30
> GENMASK and then FIELD_PREP below?

Just checked about FIELD_PREP, it works, thanks.

FIELD_PREP(GENMASK(5, 4), QCOM_DOWNLOAD_FULLDUMP)
FIELD_PREP(GENMASK(5, 4), QCOM_DOWNLOAD_NODUMP)

-Mukesh

> > +
> >   struct qcom_scm {
> >   	struct device *dev;
> >   	struct clk *core_clk;
> > @@ -440,6 +445,7 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
> >   static void qcom_scm_set_download_mode(bool enable)
> >   {
> >   	bool avail;
> > +	int val;
> What's wrong with initializing it in the same line as ret?
>
> >   	int ret = 0;
> >   
> >   	avail = __qcom_scm_is_call_available(__scm->dev,
> > @@ -448,8 +454,10 @@ static void qcom_scm_set_download_mode(bool enable)
> >   	if (avail) {
> >   		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
> >   	} else if (__scm->dload_mode_addr) {
> > -		ret = qcom_scm_io_writel(__scm->dload_mode_addr,
> > -				enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
> > +		val = (enable ? QCOM_DOWNLOAD_FULLDUMP : QCOM_DOWNLOAD_NODUMP);
> unnecessary braces
>
> Konrad
> > +		val <<= QCOM_DOWNLOAD_MODE_SHIFT;
> > +		ret = qcom_scm_io_update_field(__scm->dload_mode_addr,
> > +				QCOM_DOWNLOAD_MODE_MASK, val);
> >   	} else {
> >   		dev_err(__scm->dev,
> >   			"No available mechanism for setting download mode\n");