On Thu, 7 Apr 2022 at 13:00, Lai Jason <jasonlai.genesyslogic@xxxxxxxxx> wrote:
>
> Hi Uffe,
>
> On Thu, Mar 24, 2022 at 12:23 AM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
> >
> > On Tue, 22 Feb 2022 at 04:40, Jason Lai <jasonlai.genesyslogic@xxxxxxxxx> wrote:
> > >
> > > From: Jason Lai <jason.lai@xxxxxxxxxxxxxxxxxxx>
> > >
> > > Embed UHS-II access functionality into the MMC request processing flow.
> > >
> > > Signed-off-by: Jason Lai <jason.lai@xxxxxxxxxxxxxxxxxxx>
> > > ---
> > > drivers/mmc/core/core.c | 26 ++++++++++++++++++++++++--
> > > 1 file changed, 24 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> > > index fc3d8d61a97c..d2dcaa64bf27 100644
> > > --- a/drivers/mmc/core/core.c
> > > +++ b/drivers/mmc/core/core.c
> > > @@ -31,6 +31,7 @@
> > > #include <linux/mmc/mmc.h>
> > > #include <linux/mmc/sd.h>
> > > #include <linux/mmc/slot-gpio.h>
> > > +#include <linux/mmc/sd_uhs2.h>
> > >
> > > #define CREATE_TRACE_POINTS
> > > #include <trace/events/mmc.h>
> > > @@ -42,6 +43,7 @@
> > > #include "host.h"
> > > #include "sdio_bus.h"
> > > #include "pwrseq.h"
> > > +#include "sd_uhs2.h"
> > >
> > > #include "mmc_ops.h"
> > > #include "sd_ops.h"
> > > @@ -335,6 +337,8 @@ static int mmc_mrq_prep(struct mmc_host *host, struct mmc_request *mrq)
> > >
> > > int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
> > > {
> > > + struct uhs2_command uhs2_cmd;
> > > + u32 payload[4]; /* for maximum size */
> > > int err;
> > >
> > > init_completion(&mrq->cmd_completion);
> > > @@ -352,6 +356,13 @@ int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
> > > if (err)
> > > return err;
> > >
> > > + if (host->uhs2_caps.flags & MMC_UHS2_SUPPORT &&
> > > + host->uhs2_caps.flags & MMC_UHS2_INITIALIZED) {
> > > + uhs2_cmd.payload = payload;
> > > + mrq->cmd->uhs2_cmd = &uhs2_cmd;
> > > + sd_uhs2_prepare_cmd(host, mrq);
> > > + }
> > > +
> > > led_trigger_event(host->led, LED_FULL);
> > > __mmc_start_request(host, mrq);
> > >
> > > @@ -431,6 +442,8 @@ EXPORT_SYMBOL(mmc_wait_for_req_done);
> > > */
> > > int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
> > > {
> > > + struct uhs2_command uhs2_cmd;
> > > + u32 payload[4]; /* for maximum size */
> > > int err;
> > >
> > > /*
> > > @@ -451,6 +464,13 @@ int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq)
> > > if (err)
> > > goto out_err;
> > >
> > > + if (host->uhs2_caps.flags & MMC_UHS2_SUPPORT &&
> > > + host->uhs2_caps.flags & MMC_UHS2_INITIALIZED) {
> > > + uhs2_cmd.payload = payload;
> > > + mrq->cmd->uhs2_cmd = &uhs2_cmd;
> > > + sd_uhs2_prepare_cmd(host, mrq);
> > > + }
> > > +
> > > err = host->cqe_ops->cqe_request(host, mrq);
> > > if (err)
> > > goto out_err;
> > > @@ -899,8 +919,10 @@ static inline void mmc_set_ios(struct mmc_host *host)
> > > */
> > > void mmc_set_chip_select(struct mmc_host *host, int mode)
> > > {
> > > - host->ios.chip_select = mode;
> > > - mmc_set_ios(host);
> > > + if (!(host->uhs2_caps.flags & MMC_UHS2_INITIALIZED)) {
> > > + host->ios.chip_select = mode;
> > > + mmc_set_ios(host);
> > > + }
> >
> > As I stated for patch6, rather than having these hacks spread out into
> > the legacy code, we must not allow the ->set_ios() ops to be invoked
> > when UHS-II is being used/initialized.
> >
>
> After checking sd_uhs2.c, mmc_set_chip_select() is called in mmc_go_idle()
> and mmc_go_idle() is called in sd_uhs2_legacy_init(). Hence, I issue CMD0
> directly in sd_uhs2_legacy_init().
That works as a simple solution. But an even better option would be to
re-factor mmc_go_idle(), which then can avoid the open coding. Along
the lines like this:
1) Add a new function, _mmc_go_idle(struct mmc_host *host, bool
chip_select) - which is in principle the same as mmc_go_idle() as
today.
2) From mmc_go_idle() call _mmc_go_idle(host, true).
3) From uhs2 specific code, call _mmc_go_idle(host, false).
[...]
Kind regards
Uffe
