On 02/07/2020 18.31, Pierre Morel wrote:
> After a channel is enabled we start a SENSE_ID command using
> the SSCH instruction to recognize the control unit and device.
>
> This tests the success of SSCH, the I/O interruption and the TSCH
> instructions.
>
> The SENSE_ID command response is tested to report 0xff inside
> its reserved field and to report the same control unit type
> as the cu_type kernel argument.
>
> Without the cu_type kernel argument, the test expects a device
> with a default control unit type of 0x3832, a.k.a virtio-net-ccw.
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
[...]
> diff --git a/lib/s390x/css.h b/lib/s390x/css.h
> index 0ddceb1..9c22644 100644
> --- a/lib/s390x/css.h
> +++ b/lib/s390x/css.h
> @@ -11,6 +11,8 @@
> #ifndef CSS_H
> #define CSS_H
>
> +#define lowcore_ptr ((struct lowcore *)0x0)
I'd prefer if you could either put this into the css_lib.c file or in
lib/s390x/asm/arch_def.h.
> /* subchannel ID bit 16 must always be one */
> #define SCHID_ONE 0x00010000
>
> @@ -62,9 +64,13 @@ struct orb {
> } __attribute__ ((aligned(4)));
>
> struct scsw {
> +#define SCSW_SC_PENDING 0x00000001
> +#define SCSW_SC_PRIMARY 0x00000004
> uint32_t ctrl;
> uint32_t ccw_addr;
> uint8_t dev_stat;
> +#define SCSW_SCHS_PCI 0x80
> +#define SCSW_SCHS_IL 0x40
> uint8_t sch_stat;
> uint16_t count;
> };
> @@ -73,6 +79,7 @@ struct pmcw {
> uint32_t intparm;
> #define PMCW_DNV 0x0001
> #define PMCW_ENABLE 0x0080
> +#define PMCW_ISC_SHIFT 11
> uint16_t flags;
> uint16_t devnum;
> uint8_t lpm;
> @@ -100,6 +107,19 @@ struct irb {
> uint32_t emw[8];
> } __attribute__ ((aligned(4)));
>
> +#define CCW_CMD_SENSE_ID 0xe4
> +#define CSS_SENSEID_COMMON_LEN 8
> +struct senseid {
> + /* common part */
> + uint8_t reserved; /* always 0x'FF' */
> + uint16_t cu_type; /* control unit type */
> + uint8_t cu_model; /* control unit model */
> + uint16_t dev_type; /* device type */
> + uint8_t dev_model; /* device model */
> + uint8_t unused; /* padding byte */
> + uint8_t padding[256 - 10]; /* Extra padding for CCW */
> +} __attribute__ ((aligned(4))) __attribute__ ((packed));
> +
> /* CSS low level access functions */
>
> static inline int ssch(unsigned long schid, struct orb *addr)
> @@ -251,6 +271,16 @@ void dump_orb(struct orb *op);
>
> int css_enumerate(void);
> #define MAX_ENABLE_RETRIES 5
> -int css_enable(int schid);
> +int css_enable(int schid, int isc);
> +
> +
In case you respin: Remove one empty line?
> +/* Library functions */
> +int start_ccw1_chain(unsigned int sid, struct ccw1 *ccw);
> +int start_single_ccw(unsigned int sid, int code, void *data, int count,
> + unsigned char flags);
> +void css_irq_io(void);
> +int css_residual_count(unsigned int schid);
>
> +#define IO_SCH_ISC 3
> +void enable_io_isc(uint8_t isc);
> #endif
> diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
> index 6e5ffed..249330f 100644
> --- a/lib/s390x/css_lib.c
> +++ b/lib/s390x/css_lib.c
> @@ -16,6 +16,7 @@
> #include <interrupt.h>
> #include <asm/arch_def.h>
> #include <asm/time.h>
> +#include <asm/arch_def.h>
>
> #include <css.h>
>
> @@ -70,7 +71,17 @@ out:
> return schid;
> }
>
> -int css_enable(int schid)
> +/*
> + * css_enable: enable Subchannel
> + * @schid: Subchannel Identifier
> + * @isc: Interruption subclass for this subchannel as a number
> + * Return value:
> + * On success: 0
> + * On error the CC of the faulty instruction
> + * or -1 if the retry count is exceeded.
> + *
> + */
> +int css_enable(int schid, int isc)
> {
> struct pmcw *pmcw = &schib.pmcw;
> int retry_count = 0;
> @@ -92,6 +103,9 @@ retry:
> /* Update the SCHIB to enable the channel */
> pmcw->flags |= PMCW_ENABLE;
>
> + /* Set Interruption Subclass to IO_SCH_ISC */
> + pmcw->flags |= (isc << PMCW_ISC_SHIFT);
> +
> /* Tell the CSS we want to modify the subchannel */
> cc = msch(schid, &schib);
> if (cc) {
> @@ -114,6 +128,7 @@ retry:
> return cc;
> }
>
> + report_info("stsch: flags: %04x", pmcw->flags);
> if (pmcw->flags & PMCW_ENABLE) {
> report_info("stsch: sch %08x enabled after %d retries",
> schid, retry_count);
> @@ -129,3 +144,134 @@ retry:
> schid, retry_count, pmcw->flags);
> return -1;
> }
> +
> +static struct irb irb;
> +
> +void css_irq_io(void)
> +{
> + int ret = 0;
> + char *flags;
> + int sid;
> +
> + report_prefix_push("Interrupt");
> + sid = lowcore_ptr->subsys_id_word;
> + /* Lowlevel set the SID as interrupt parameter. */
> + if (lowcore_ptr->io_int_param != sid) {
> + report(0,
> + "io_int_param: %x differs from subsys_id_word: %x",
> + 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");
> + ret = tsch(sid, &irb);
> + switch (ret) {
> + case 1:
> + dump_irb(&irb);
> + flags = dump_scsw_flags(irb.scsw.ctrl);
> + report(0,
> + "I/O interrupt, CC 1 but tsch reporting sch %08x as not status pending: %s",
> + sid, flags);
> + break;
> + case 2:
> + report(0, "tsch returns unexpected CC 2");
> + break;
> + case 3:
> + report(0, "tsch reporting sch %08x as not operational", sid);
> + break;
> + case 0:
> + /* Stay humble on success */
> + break;
> + }
> +pop:
> + report_prefix_pop();
> + lowcore_ptr->io_old_psw.mask &= ~PSW_MASK_WAIT;
> +}
> +
> +int start_ccw1_chain(unsigned int sid, struct ccw1 *ccw)
> +{
> + struct orb orb = {
> + .intparm = sid,
> + .ctrl = ORB_CTRL_ISIC|ORB_CTRL_FMT|ORB_LPM_DFLT,
> + .cpa = (unsigned int) (unsigned long)ccw,
> + };
> +
> + return ssch(sid, &orb);
> +}
> +
> +/*
> + * In the future, we want to implement support for CCW chains;
> + * for that, we will need to work with ccw1 pointers.
> + */
> +static struct ccw1 unique_ccw;
> +
> +int start_single_ccw(unsigned int sid, int code, void *data, int count,
> + unsigned char flags)
> +{
> + int cc;
> + struct ccw1 *ccw = &unique_ccw;
> +
> + report_prefix_push("start_subchannel");
> + /* Build the CCW chain with a single CCW */
> + ccw->code = code;
> + ccw->flags = flags; /* No flags need to be set */
> + ccw->count = count;
> + ccw->data_address = (int)(unsigned long)data;
> +
> + cc = start_ccw1_chain(sid, ccw);
> + if (cc) {
> + report(0, "start_ccw_chain failed ret=%d", cc);
> + report_prefix_pop();
> + return cc;
> + }
> + report_prefix_pop();
> + return 0;
> +}
> +
> +/*
> + * css_residual_count
> + * We expect no residual count when the ORB request was successful
> + * The residual count is valid when the subchannel is status pending
> + * with primary status and device status only or device status and
> + * subchannel status with PCI or incorrect length.
> + * Return value:
> + * Success: the residual count
> + * Not meaningful: -1 (-1 can not be a valid count)
> + */
> +int css_residual_count(unsigned int schid)
> +{
> +
> + if (!(irb.scsw.ctrl & (SCSW_SC_PENDING | SCSW_SC_PRIMARY)))
> + goto fail;
> +
> + if (irb.scsw.dev_stat)
> + if (irb.scsw.sch_stat & ~(SCSW_SCHS_PCI | SCSW_SCHS_IL))
> + goto fail;
> +
> + return irb.scsw.count;
> +
> +fail:
> + report_info("sch status %02x", irb.scsw.sch_stat);
> + report_info("dev status %02x", irb.scsw.dev_stat);
> + report_info("ctrl status %08x", irb.scsw.ctrl);
> + report_info("count %04x", irb.scsw.count);
> + report_info("ccw addr %08x", irb.scsw.ccw_addr);
> + return -1;
> +}
> +
> +/*
> + * enable_io_isc: setup ISC in Control Register 6
> + * @isc: The interruption Sub Class as a bitfield
> + */
> +void enable_io_isc(uint8_t isc)
> +{
> + uint64_t value;
> +
> + value = (uint64_t)isc << 24;
> + lctlg(6, value);
> +}
> diff --git a/s390x/css.c b/s390x/css.c
> index 72aec43..60e6434 100644
> --- a/s390x/css.c
> +++ b/s390x/css.c
> @@ -19,7 +19,11 @@
>
> #include <css.h>
>
> +#define DEFAULT_CU_TYPE 0x3832 /* virtio-ccw */
> +static unsigned long cu_type = DEFAULT_CU_TYPE;
> +
> static int test_device_sid;
> +static struct senseid senseid;
>
> static void test_enumerate(void)
> {
> @@ -40,17 +44,104 @@ static void test_enable(void)
> return;
> }
>
> - cc = css_enable(test_device_sid);
> + cc = css_enable(test_device_sid, IO_SCH_ISC);
>
> report(cc == 0, "Enable subchannel %08x", test_device_sid);
> }
>
> +/*
> + * test_sense
> + * Pre-requisits:
> + * - We need the test device as the first recognized
> + * device by the enumeration.
> + */
> +static void test_sense(void)
> +{
> + int ret;
> + int len;
> +
> + if (!test_device_sid) {
> + report_skip("No device");
> + return;
> + }
> +
> + ret = css_enable(test_device_sid, IO_SCH_ISC);
> + if (ret) {
> + report(0,
> + "Could not enable the subchannel: %08x",
> + test_device_sid);
> + return;
> + }
> +
> + ret = register_io_int_func(css_irq_io);
> + if (ret) {
> + report(0, "Could not register IRQ handler");
> + goto unreg_cb;
> + }
> +
> + lowcore_ptr->io_int_param = 0;
> +
> + memset(&senseid, 0, sizeof(senseid));
> + ret = start_single_ccw(test_device_sid, CCW_CMD_SENSE_ID,
> + &senseid, sizeof(senseid), CCW_F_SLI);
> + if (ret) {
> + report(0, "ssch failed for SENSE ID on sch %08x with cc %d",
> + test_device_sid, ret);
> + goto unreg_cb;
> + }
I'd maybe rather do something like:
report(ret == 0, "SENSE ID on sch %08x has good CC (%d)", ...)
if (ret)
goto unreg_cb;
and avoid report(0, ...) statements. Also for the other tests below. But
maybe that's really just a matter of taste.
> + wait_for_interrupt(PSW_MASK_IO);
> +
> + if (lowcore_ptr->io_int_param != test_device_sid) {
> + report(0, "ssch succeeded but interrupt parameter is wrong: expect %08x got %08x",
> + test_device_sid, lowcore_ptr->io_int_param);
> + goto unreg_cb;
> + }
> +
> + ret = css_residual_count(test_device_sid);
> + if (ret < 0) {
> + report(0, "ssch succeeded for SENSE ID but can not get a valid residual count");
> + goto unreg_cb;
> + }
> +
> + len = sizeof(senseid) - ret;
> + if (ret && len < CSS_SENSEID_COMMON_LEN) {
> + report(0,
> + "ssch succeeded for SENSE ID but report a too short length: %d",
> + ret);
> + goto unreg_cb;
> + }
> +
> + if (ret && len)
> + report_info("ssch succeeded for SENSE ID but report a shorter length: %d",
> + len);
> +
> + if (senseid.reserved != 0xff) {
> + report(0,
> + "ssch succeeded for SENSE ID but reports garbage: %x",
> + senseid.reserved);
> + goto unreg_cb;
> + }
> +
> + report_info("senseid length read: %d", ret);
> + report_info("reserved %02x cu_type %04x cu_model %02x dev_type %04x dev_model %02x",
> + senseid.reserved, senseid.cu_type, senseid.cu_model,
> + senseid.dev_type, senseid.dev_model);
> +
> + report(senseid.cu_type == cu_type, "cu_type: expect 0x%04x got 0x%04x",
> + (uint16_t) cu_type, senseid.cu_type);
> +
> +unreg_cb:
> + unregister_io_int_func(css_irq_io);
> +}
> +
> static struct {
> const char *name;
> void (*func)(void);
> } tests[] = {
> { "enumerate (stsch)", test_enumerate },
> { "enable (msch)", test_enable },
> + { "sense (ssch/tsch)", test_sense },
> { NULL, NULL }
> };
>
> @@ -59,6 +150,7 @@ int main(int argc, char *argv[])
> int i;
>
> report_prefix_push("Channel Subsystem");
> + enable_io_isc(0x80 >> IO_SCH_ISC);
> for (i = 0; tests[i].name; i++) {
> report_prefix_push(tests[i].name);
> tests[i].func();
Apart from the nits, I'm fine with the patch.
Acked-by: Thomas Huth <thuth@xxxxxxxxxx>
