From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:61680 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728690AbgGPNEO (ORCPT ); Thu, 16 Jul 2020 09:04:14 -0400 From: Pierre Morel Subject: [PATCH v14 9/9] s390x: css: ssch/tsch with sense and interrupt Date: Thu, 16 Jul 2020 15:04:05 +0200 Message-Id: <1594904645-32499-1-git-send-email-pmorel@linux.ibm.com> In-Reply-To: References: Sender: linux-s390-owner@vger.kernel.org List-ID: To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com, cohuck@redhat.com, drjones@redhat.com 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 Acked-by: Thomas Huth Reviewed-by: Cornelia Huck --- lib/s390x/asm/arch_def.h | 1 + lib/s390x/css.h | 35 ++++++++ lib/s390x/css_lib.c | 177 +++++++++++++++++++++++++++++++++++++++ s390x/css.c | 80 ++++++++++++++++++ 4 files changed, 293 insertions(+) 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 63a70f1..221b67c 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; }; @@ -102,6 +113,19 @@ 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 - 8]; /* Extended part */ +} __attribute__ ((aligned(4))) __attribute__ ((packed)); + /* CSS low level access functions */ static inline int ssch(unsigned long schid, struct orb *addr) @@ -256,4 +280,15 @@ 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 e47a945..8e02371 100644 --- a/lib/s390x/css_lib.c +++ b/lib/s390x/css_lib.c @@ -16,6 +16,7 @@ #include #include #include +#include #include @@ -141,3 +142,179 @@ 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 or sch end. Dev. status: %02x", + irb.scsw.dev_stat); + ret = -1; + goto end; + } + + if (irb.scsw.sch_stat & ~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))) + return -1; + + if (irb.scsw.dev_stat) + if (irb.scsw.sch_stat & ~(SCSW_SCHS_PCI | SCSW_SCHS_IL)) + return -1; + + return irb.scsw.count; +} + +/* + * 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 +#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(); -- 2.25.1