diff mbox series

[kvm-unit-tests,v11,9/9] s390x: css: ssch/tsch with sense and interrupt

Message ID 1594282068-11054-10-git-send-email-pmorel@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: Testing the Channel Subsystem I/O | expand

Commit Message

Pierre Morel July 9, 2020, 8:07 a.m. UTC
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@linux.ibm.com>
---
 lib/s390x/asm/arch_def.h |   1 +
 lib/s390x/css.h          |  35 ++++++++
 lib/s390x/css_lib.c      | 183 +++++++++++++++++++++++++++++++++++++++
 s390x/css.c              |  80 +++++++++++++++++
 4 files changed, 299 insertions(+)

Comments

Cornelia Huck July 9, 2020, 12:13 p.m. UTC | #1
On Thu,  9 Jul 2020 10:07:48 +0200
Pierre Morel <pmorel@linux.ibm.com> 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@linux.ibm.com>
> ---
>  lib/s390x/asm/arch_def.h |   1 +
>  lib/s390x/css.h          |  35 ++++++++
>  lib/s390x/css_lib.c      | 183 +++++++++++++++++++++++++++++++++++++++
>  s390x/css.c              |  80 +++++++++++++++++
>  4 files changed, 299 insertions(+)

(...)

> diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
> index eda68a4..c64edd5 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>
>  
> @@ -103,6 +104,9 @@ retry:
>  	/* Update the SCHIB to enable the channel and set the ISC */
>  	pmcw->flags |= flags;
>  
> +	/* Set Interruption Subclass to IO_SCH_ISC */
> +	pmcw->flags |= (isc << PMCW_ISC_SHIFT);

But isn't the isc already contained in 'flags'? I think you should just
delete these two lines.

> +
>  	/* Tell the CSS we want to modify the subchannel */
>  	cc = msch(schid, &schib);
>  	if (cc) {

(...)

> +/* wait_and_check_io_completion:
> + * @schid: the subchannel ID
> + *
> + * Makes the most common check to validate a successful I/O
> + * completion.
> + * Only report failures.
> + */
> +int wait_and_check_io_completion(int schid)
> +{
> +	int ret = 0;
> +
> +	wait_for_interrupt(PSW_MASK_IO);
> +
> +	report_prefix_push("check I/O completion");
> +
> +	if (lowcore_ptr->io_int_param != schid) {
> +		report(0, "interrupt parameter: expected %08x got %08x",
> +		       schid, lowcore_ptr->io_int_param);
> +		ret = -1;
> +		goto end;
> +	}
> +
> +	/* Verify that device status is valid */
> +	if (!(irb.scsw.ctrl & SCSW_SC_PENDING)) {
> +		report(0, "No status pending after interrupt. Subch Ctrl: %08x",
> +		       irb.scsw.ctrl);
> +		ret = -1;
> +		goto end;
> +	}
> +
> +	if (!(irb.scsw.ctrl & (SCSW_SC_SECONDARY | SCSW_SC_PRIMARY))) {
> +		report(0, "Primary or secondary status missing. Subch Ctrl: %08x",
> +		       irb.scsw.ctrl);
> +		ret = -1;
> +		goto end;
> +	}
> +
> +	if (!(irb.scsw.dev_stat & (SCSW_DEVS_DEV_END | SCSW_DEVS_SCH_END))) {
> +		report(0, "No device end nor sch end. Dev. status: %02x",

s/nor/or/ ?

> +		       irb.scsw.dev_stat);
> +		ret = -1;
> +		goto end;
> +	}
> +
> +	if (irb.scsw.sch_stat & !(SCSW_SCHS_PCI | SCSW_SCHS_IL)) {

Did you mean ~(SCSW_SCHS_PCI | SCSW_SCHS_IL)?

If yes, why do think a PCI may show up?

> +		report_info("Unexpected Subch. status %02x", irb.scsw.sch_stat);
> +		ret = -1;
> +		goto end;
> +	}
> +
> +end:
> +	report_prefix_pop();
> +	return ret;

(...)
Pierre Morel July 9, 2020, 1:18 p.m. UTC | #2
On 2020-07-09 14:13, Cornelia Huck wrote:
> On Thu,  9 Jul 2020 10:07:48 +0200
> Pierre Morel <pmorel@linux.ibm.com> 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@linux.ibm.com>
>> ---
>>   lib/s390x/asm/arch_def.h |   1 +
>>   lib/s390x/css.h          |  35 ++++++++
>>   lib/s390x/css_lib.c      | 183 +++++++++++++++++++++++++++++++++++++++
>>   s390x/css.c              |  80 +++++++++++++++++
>>   4 files changed, 299 insertions(+)
> 
> (...)
> 
>> diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
>> index eda68a4..c64edd5 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>
>>   
>> @@ -103,6 +104,9 @@ retry:
>>   	/* Update the SCHIB to enable the channel and set the ISC */
>>   	pmcw->flags |= flags;
>>   
>> +	/* Set Interruption Subclass to IO_SCH_ISC */
>> +	pmcw->flags |= (isc << PMCW_ISC_SHIFT);
> 
> But isn't the isc already contained in 'flags'? I think you should just
> delete these two lines.

right.

> 
>> +
>>   	/* Tell the CSS we want to modify the subchannel */
>>   	cc = msch(schid, &schib);
>>   	if (cc) {
> 
> (...)
> 
>> +/* wait_and_check_io_completion:
>> + * @schid: the subchannel ID
>> + *
>> + * Makes the most common check to validate a successful I/O
>> + * completion.
>> + * Only report failures.
>> + */
>> +int wait_and_check_io_completion(int schid)
>> +{
>> +	int ret = 0;
>> +
>> +	wait_for_interrupt(PSW_MASK_IO);
>> +
>> +	report_prefix_push("check I/O completion");
>> +
>> +	if (lowcore_ptr->io_int_param != schid) {
>> +		report(0, "interrupt parameter: expected %08x got %08x",
>> +		       schid, lowcore_ptr->io_int_param);
>> +		ret = -1;
>> +		goto end;
>> +	}
>> +
>> +	/* Verify that device status is valid */
>> +	if (!(irb.scsw.ctrl & SCSW_SC_PENDING)) {
>> +		report(0, "No status pending after interrupt. Subch Ctrl: %08x",
>> +		       irb.scsw.ctrl);
>> +		ret = -1;
>> +		goto end;
>> +	}
>> +
>> +	if (!(irb.scsw.ctrl & (SCSW_SC_SECONDARY | SCSW_SC_PRIMARY))) {
>> +		report(0, "Primary or secondary status missing. Subch Ctrl: %08x",
>> +		       irb.scsw.ctrl);
>> +		ret = -1;
>> +		goto end;
>> +	}
>> +
>> +	if (!(irb.scsw.dev_stat & (SCSW_DEVS_DEV_END | SCSW_DEVS_SCH_END))) {
>> +		report(0, "No device end nor sch end. Dev. status: %02x",
> 
> s/nor/or/ ?

OK

> 
>> +		       irb.scsw.dev_stat);
>> +		ret = -1;
>> +		goto end;
>> +	}
>> +
>> +	if (irb.scsw.sch_stat & !(SCSW_SCHS_PCI | SCSW_SCHS_IL)) {
> 
> Did you mean ~(SCSW_SCHS_PCI | SCSW_SCHS_IL)?

grrr... yes, thanks.

> 
> If yes, why do think a PCI may show up?

Should not in the current implementation.
I thought I can add it as a general test.

Regards,
Pierre
Cornelia Huck July 9, 2020, 1:33 p.m. UTC | #3
On Thu, 9 Jul 2020 15:18:25 +0200
Pierre Morel <pmorel@linux.ibm.com> wrote:

> On 2020-07-09 14:13, Cornelia Huck wrote:
> > On Thu,  9 Jul 2020 10:07:48 +0200
> > Pierre Morel <pmorel@linux.ibm.com> wrote:

> >> +	if (irb.scsw.sch_stat & !(SCSW_SCHS_PCI | SCSW_SCHS_IL)) {  
> > 
> > Did you mean ~(SCSW_SCHS_PCI | SCSW_SCHS_IL)?  
> 
> grrr... yes, thanks.
> 
> > 
> > If yes, why do think a PCI may show up?  
> 
> Should not in the current implementation.
> I thought I can add it as a general test.

Yeah, maybe in the future. But for now, I think it is a bit confusing.
Pierre Morel July 9, 2020, 1:38 p.m. UTC | #4
On 2020-07-09 15:33, Cornelia Huck wrote:
> On Thu, 9 Jul 2020 15:18:25 +0200
> Pierre Morel <pmorel@linux.ibm.com> wrote:
> 
>> On 2020-07-09 14:13, Cornelia Huck wrote:
>>> On Thu,  9 Jul 2020 10:07:48 +0200
>>> Pierre Morel <pmorel@linux.ibm.com> wrote:
> 
>>>> +	if (irb.scsw.sch_stat & !(SCSW_SCHS_PCI | SCSW_SCHS_IL)) {
>>>
>>> Did you mean ~(SCSW_SCHS_PCI | SCSW_SCHS_IL)?
>>
>> grrr... yes, thanks.
>>
>>>
>>> If yes, why do think a PCI may show up?
>>
>> Should not in the current implementation.
>> I thought I can add it as a general test.
> 
> Yeah, maybe in the future. But for now, I think it is a bit confusing.
> 

OK then I just remove it.
diff mbox series

Patch

diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
index 022a564..edc06ef 100644
--- a/lib/s390x/asm/arch_def.h
+++ b/lib/s390x/asm/arch_def.h
@@ -16,6 +16,7 @@  struct psw {
 };
 
 #define PSW_MASK_EXT			0x0100000000000000UL
+#define PSW_MASK_IO			0x0200000000000000UL
 #define PSW_MASK_DAT			0x0400000000000000UL
 #define PSW_MASK_WAIT			0x0002000000000000UL
 #define PSW_MASK_PSTATE			0x0001000000000000UL
diff --git a/lib/s390x/css.h b/lib/s390x/css.h
index 106479d..e754f9f 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)
+
 /* subchannel ID bit 16 must always be one */
 #define SCHID_ONE	0x00010000
 
@@ -62,9 +64,18 @@  struct orb {
 } __attribute__ ((aligned(4)));
 
 struct scsw {
+#define SCSW_SC_PENDING		0x00000001
+#define SCSW_SC_SECONDARY	0x00000002
+#define SCSW_SC_PRIMARY		0x00000004
+#define SCSW_SC_INTERMEDIATE	0x00000008
+#define SCSW_SC_ALERT		0x00000010
 	uint32_t ctrl;
 	uint32_t ccw_addr;
+#define SCSW_DEVS_DEV_END	0x04
+#define SCSW_DEVS_SCH_END	0x08
 	uint8_t  dev_stat;
+#define SCSW_SCHS_PCI	0x80
+#define SCSW_SCHS_IL	0x40
 	uint8_t  sch_stat;
 	uint16_t count;
 };
@@ -101,6 +112,19 @@  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)
@@ -255,4 +279,15 @@  int css_enumerate(void);
 
 #define IO_SCH_ISC      3
 int css_enable(int schid, int isc);
+
+/* 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);
+
+void enable_io_isc(uint8_t isc);
+int wait_and_check_io_completion(int schid);
+
 #endif
diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
index eda68a4..c64edd5 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>
 
@@ -103,6 +104,9 @@  retry:
 	/* Update the SCHIB to enable the channel and set the ISC */
 	pmcw->flags |= flags;
 
+	/* 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) {
@@ -140,3 +144,182 @@  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, but tsch returns CC 1 for subchannel %08x. SCSW flags: %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;
+	ccw->count = count;
+	ccw->data_address = (int)(unsigned long)data;
+
+	cc = start_ccw1_chain(sid, ccw);
+	if (cc) {
+		report(0, "cc = %d", cc);
+		report_prefix_pop();
+		return cc;
+	}
+	report_prefix_pop();
+	return 0;
+}
+
+/* wait_and_check_io_completion:
+ * @schid: the subchannel ID
+ *
+ * Makes the most common check to validate a successful I/O
+ * completion.
+ * Only report failures.
+ */
+int wait_and_check_io_completion(int schid)
+{
+	int ret = 0;
+
+	wait_for_interrupt(PSW_MASK_IO);
+
+	report_prefix_push("check I/O completion");
+
+	if (lowcore_ptr->io_int_param != schid) {
+		report(0, "interrupt parameter: expected %08x got %08x",
+		       schid, lowcore_ptr->io_int_param);
+		ret = -1;
+		goto end;
+	}
+
+	/* Verify that device status is valid */
+	if (!(irb.scsw.ctrl & SCSW_SC_PENDING)) {
+		report(0, "No status pending after interrupt. Subch Ctrl: %08x",
+		       irb.scsw.ctrl);
+		ret = -1;
+		goto end;
+	}
+
+	if (!(irb.scsw.ctrl & (SCSW_SC_SECONDARY | SCSW_SC_PRIMARY))) {
+		report(0, "Primary or secondary status missing. Subch Ctrl: %08x",
+		       irb.scsw.ctrl);
+		ret = -1;
+		goto end;
+	}
+
+	if (!(irb.scsw.dev_stat & (SCSW_DEVS_DEV_END | SCSW_DEVS_SCH_END))) {
+		report(0, "No device end nor sch end. Dev. status: %02x",
+		       irb.scsw.dev_stat);
+		ret = -1;
+		goto end;
+	}
+
+	if (irb.scsw.sch_stat & !(SCSW_SCHS_PCI | SCSW_SCHS_IL)) {
+		report_info("Unexpected Subch. status %02x", irb.scsw.sch_stat);
+		ret = -1;
+		goto end;
+	}
+
+end:
+	report_prefix_pop();
+	return ret;
+}
+
+/*
+ * css_residual_count
+ * Return the residual count, if it is valid.
+ *
+ * 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 invalid;
+
+	if (irb.scsw.dev_stat)
+		if (irb.scsw.sch_stat & ~(SCSW_SCHS_PCI | SCSW_SCHS_IL))
+			goto invalid;
+
+	return irb.scsw.count;
+
+invalid:
+	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 f314a0c..ee3bc83 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)
 {
@@ -45,12 +49,87 @@  static void test_enable(void)
 	report(cc == 0, "Enable subchannel %08x", test_device_sid);
 }
 
+/*
+ * test_sense
+ * Pre-requisites:
+ * - 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");
+		return;
+	}
+
+	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)
+		goto error;
+
+	if (wait_and_check_io_completion(test_device_sid) < 0)
+		goto error;
+
+	/* Test transfer completion */
+	report_prefix_push("ssch transfer completion");
+
+	ret = css_residual_count(test_device_sid);
+
+	if (ret < 0) {
+		report_info("no valid residual count");
+	} else if (ret != 0) {
+		len = sizeof(senseid) - ret;
+		if (ret && len < CSS_SENSEID_COMMON_LEN) {
+			report(0, "transferred a too short length: %d", ret);
+			goto error;
+		} else if (ret && len)
+			report_info("transferred a shorter length: %d", len);
+	}
+
+	if (senseid.reserved != 0xff) {
+		report(0, "transferred garbage: 0x%02x", senseid.reserved);
+		goto error;
+	}
+
+	report_prefix_pop();
+
+	report_info("reserved 0x%02x cu_type 0x%04x cu_model 0x%02x dev_type 0x%04x dev_model 0x%02x",
+		    senseid.reserved, senseid.cu_type, senseid.cu_model,
+		    senseid.dev_type, senseid.dev_model);
+
+	report(senseid.cu_type == cu_type, "cu_type expected 0x%04x got 0x%04x",
+	       (uint16_t) cu_type, senseid.cu_type);
+
+error:
+	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 +138,7 @@  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();