Message ID | 20200414104120.1.Ic70288f256ff0be65cac6a600367212dfe39f6c9@changeid (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | soc: qcom: rpmh-rsc: Factor "tcs_reg_addr" and "tcs_cmd_addr" calculation | expand |
On Tue, 2020-04-14 at 10:41 -0700, Douglas Anderson wrote: > We can make some of the register access functions more readable by > factoring out the calculations a little bit. unrelated trivia: > diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c [] > static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, > u32 data) > { > - writel(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); > + writel(data, tcs_reg_addr(drv, reg, tcs_id)); > for (;;) { > - if (data == readl(drv->tcs_base + reg + > - RSC_DRV_TCS_OFFSET * tcs_id)) > + if (data == readl(tcs_reg_addr(drv, reg, tcs_id))) > break; > udelay(1); > } There a lockup potential here. It might be better to use some max loop counter with an error/warning emitted instead of a continuous retry.
Hi, On Tue, Apr 14, 2020 at 10:58 AM Joe Perches <joe@perches.com> wrote: > > On Tue, 2020-04-14 at 10:41 -0700, Douglas Anderson wrote: > > We can make some of the register access functions more readable by > > factoring out the calculations a little bit. > > unrelated trivia: > > > diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c > [] > > static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, > > u32 data) > > { > > - writel(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); > > + writel(data, tcs_reg_addr(drv, reg, tcs_id)); > > for (;;) { > > - if (data == readl(drv->tcs_base + reg + > > - RSC_DRV_TCS_OFFSET * tcs_id)) > > + if (data == readl(tcs_reg_addr(drv, reg, tcs_id))) > > break; > > udelay(1); > > } > > There a lockup potential here. > > It might be better to use some max loop counter with > an error/warning emitted instead of a continuous retry. Yeah, I noticed that too but I assumed that it was probably OK. I think in this case it's really just confirming that the write made it across the bus since it's checking the same bit that it's writing. ...but I wouldn't be opposed to this changing to use readl_poll_timeout(). -Doug
Quoting Douglas Anderson (2020-04-14 10:41:34) > We can make some of the register access functions more readable by > factoring out the calculations a little bit. > > Suggested-by: Joe Perches <joe@perches.com> > Signed-off-by: Douglas Anderson <dianders@chromium.org> > --- > > drivers/soc/qcom/rpmh-rsc.c | 27 ++++++++++++++++++--------- > 1 file changed, 18 insertions(+), 9 deletions(-) > > diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c > index 732316bb67dc..de1f9c7732e1 100644 > --- a/drivers/soc/qcom/rpmh-rsc.c > +++ b/drivers/soc/qcom/rpmh-rsc.c > @@ -136,36 +136,45 @@ > * +---------------------------------------------------+ > */ > > +static inline void __iomem * > +tcs_reg_addr(struct rsc_drv *drv, int reg, int tcs_id) const drv? > +{ > + return drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg; > +} > + > +static inline void __iomem * > +tcs_cmd_addr(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) const drv? > +{ > + return tcs_reg_addr(drv, reg, tcs_id) + RSC_DRV_CMD_OFFSET * cmd_id; > +} > +
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 732316bb67dc..de1f9c7732e1 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -136,36 +136,45 @@ * +---------------------------------------------------+ */ +static inline void __iomem * +tcs_reg_addr(struct rsc_drv *drv, int reg, int tcs_id) +{ + return drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg; +} + +static inline void __iomem * +tcs_cmd_addr(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) +{ + return tcs_reg_addr(drv, reg, tcs_id) + RSC_DRV_CMD_OFFSET * cmd_id; +} + static u32 read_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) { - return readl_relaxed(drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg + - RSC_DRV_CMD_OFFSET * cmd_id); + return readl_relaxed(tcs_cmd_addr(drv, reg, tcs_id, cmd_id)); } static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id) { - return readl_relaxed(drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); + return readl_relaxed(tcs_reg_addr(drv, reg, tcs_id)); } static void write_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id, u32 data) { - writel_relaxed(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg + - RSC_DRV_CMD_OFFSET * cmd_id); + writel_relaxed(data, tcs_cmd_addr(drv, reg, tcs_id, cmd_id)); } static void write_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, u32 data) { - writel_relaxed(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); + writel_relaxed(data, tcs_reg_addr(drv, reg, tcs_id)); } static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, u32 data) { - writel(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); + writel(data, tcs_reg_addr(drv, reg, tcs_id)); for (;;) { - if (data == readl(drv->tcs_base + reg + - RSC_DRV_TCS_OFFSET * tcs_id)) + if (data == readl(tcs_reg_addr(drv, reg, tcs_id))) break; udelay(1); }
We can make some of the register access functions more readable by factoring out the calculations a little bit. Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- drivers/soc/qcom/rpmh-rsc.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-)