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>
---
lib/s390x/asm/arch_def.h | 1 +
lib/s390x/css.h | 32 ++++++++-
lib/s390x/css_lib.c | 148 ++++++++++++++++++++++++++++++++++++++-
s390x/css.c | 94 ++++++++++++++++++++++++-
4 files changed, 272 insertions(+), 3 deletions(-)
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 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)
+
/* 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);
+
+
+/* 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;
+ }
+
+ 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();
--
2.25.1
