On 3/12/21 11:41 AM, Pierre Morel wrote:
> In order to ease the writing of tests based on:
> - interrupt
> - enabling a subchannel
> - using multiple I/O on a channel without disabling it
>
> We do the following simplifications:
> - the I/O interrupt handler is registered on CSS initialization
> - We do not enable again a subchannel in senseid if it is already
> enabled
> - we add a css_enabled() function to test if a subchannel is enabled
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Acked-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> ---
> lib/s390x/css.h | 1 +
> lib/s390x/css_lib.c | 41 ++++++++++++++++++++++++++---------------
> s390x/css.c | 15 +++++----------
> 3 files changed, 32 insertions(+), 25 deletions(-)
>
> diff --git a/lib/s390x/css.h b/lib/s390x/css.h
> index 3dc2f31..b9e4c08 100644
> --- a/lib/s390x/css.h
> +++ b/lib/s390x/css.h
> @@ -278,6 +278,7 @@ int css_enumerate(void);
>
> #define IO_SCH_ISC 3
> int css_enable(int schid, int isc);
> +bool css_enabled(int schid);
>
> /* Library functions */
> int start_ccw1_chain(unsigned int sid, struct ccw1 *ccw);
> diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
> index 3c1acbf..a97d61e 100644
> --- a/lib/s390x/css_lib.c
> +++ b/lib/s390x/css_lib.c
> @@ -161,6 +161,31 @@ out:
> return schid;
> }
>
> +/*
> + * css_enabled: report if the subchannel is enabled
> + * @schid: Subchannel Identifier
> + * Return value:
> + * true if the subchannel is enabled
> + * false otherwise
> + */
> +bool css_enabled(int schid)
> +{
> + struct pmcw *pmcw = &schib.pmcw;
> + int cc;
> +
> + cc = stsch(schid, &schib);
> + if (cc) {
> + report_info("stsch: updating sch %08x failed with cc=%d",
> + schid, cc);
> + return false;
> + }
> +
> + if (!(pmcw->flags & PMCW_ENABLE)) {
> + report_info("stsch: sch %08x not enabled", schid);
> + return false;
> + }
> + return true;
> +}
> /*
> * css_enable: enable the subchannel with the specified ISC
> * @schid: Subchannel Identifier
> @@ -210,18 +235,8 @@ retry:
> /*
> * Read the SCHIB again to verify the enablement
> */
> - cc = stsch(schid, &schib);
> - if (cc) {
> - report_info("stsch: updating sch %08x failed with cc=%d",
> - schid, cc);
> - return cc;
> - }
> -
> - if ((pmcw->flags & flags) == flags) {
> - report_info("stsch: sch %08x successfully modified after %d retries",
> - schid, retry_count);
> + if (css_enabled(schid))
> return 0;
> - }
>
> if (retry_count++ < MAX_ENABLE_RETRIES) {
> mdelay(10); /* the hardware was not ready, give it some time */
> @@ -250,10 +265,6 @@ void css_irq_io(void)
> lowcore_ptr->io_int_param, sid);
> goto pop;
> }
> - report_info("subsys_id_word: %08x io_int_param %08x io_int_word %08x",
> - lowcore_ptr->subsys_id_word,
> - lowcore_ptr->io_int_param,
> - lowcore_ptr->io_int_word);
> report_prefix_pop();
>
> report_prefix_push("tsch");
> diff --git a/s390x/css.c b/s390x/css.c
> index 12036b3..a477833 100644
> --- a/s390x/css.c
> +++ b/s390x/css.c
> @@ -25,6 +25,7 @@ static unsigned long cu_type = DEFAULT_CU_TYPE;
>
> static int test_device_sid;
> static struct senseid *senseid;
> +struct ccw1 *ccw;
>
> static void test_enumerate(void)
> {
> @@ -58,7 +59,6 @@ static void test_enable(void)
> */
> static void test_sense(void)
> {
> - struct ccw1 *ccw;
> int ret;
> int len;
>
> @@ -74,18 +74,12 @@ static void test_sense(void)
> return;
> }
>
> - ret = register_io_int_func(css_irq_io);
> - if (ret) {
> - report(0, "Could not register IRQ handler");
> - return;
> - }
> -
> lowcore_ptr->io_int_param = 0;
>
> senseid = alloc_io_mem(sizeof(*senseid), 0);
> if (!senseid) {
> report(0, "Allocation of senseid");
> - goto error_senseid;
> + return;
> }
>
> ccw = ccw_alloc(CCW_CMD_SENSE_ID, senseid, sizeof(*senseid), CCW_F_SLI);
> @@ -137,12 +131,13 @@ error:
> free_io_mem(ccw, sizeof(*ccw));
> error_ccw:
> free_io_mem(senseid, sizeof(*senseid));
> -error_senseid:
> - unregister_io_int_func(css_irq_io);
> }
>
> static void css_init(void)
> {
> + assert(register_io_int_func(css_irq_io) == 0);
> + lowcore_ptr->io_int_param = 0;
> +
> report(get_chsc_scsc(), "Store Channel Characteristics");
> }
>
>
