From: Pierre Morel <pmorel@xxxxxxxxxxxxx> CSS characteristics exposes the features of the Channel SubSystem. Let's use Store Channel Subsystem Characteristics to retrieve the features of the CSS. Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> Acked-by: Janosch Frank <frankja@xxxxxxxxxxxxx> Link: https://lore.kernel.org/kvm/1615545714-13747-2-git-send-email-pmorel@xxxxxxxxxxxxx/ Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> --- lib/s390x/css.h | 66 ++++++++++++++++++++++++++++++++ lib/s390x/css_lib.c | 93 ++++++++++++++++++++++++++++++++++++++++++++- s390x/css.c | 8 ++++ 3 files changed, 166 insertions(+), 1 deletion(-) diff --git a/lib/s390x/css.h b/lib/s390x/css.h index 3e574455..3dc2f313 100644 --- a/lib/s390x/css.h +++ b/lib/s390x/css.h @@ -288,4 +288,70 @@ int css_residual_count(unsigned int schid); void enable_io_isc(uint8_t isc); int wait_and_check_io_completion(int schid); +/* + * CHSC definitions + */ +struct chsc_header { + uint16_t len; + uint16_t code; +}; + +/* Store Channel Subsystem Characteristics */ +struct chsc_scsc { + struct chsc_header req; + uint16_t req_fmt; + uint8_t cssid; + uint8_t reserved[9]; + struct chsc_header res; + uint32_t res_fmt; + uint64_t general_char[255]; + uint64_t chsc_char[254]; +}; + +extern struct chsc_scsc *chsc_scsc; +#define CHSC_SCSC 0x0010 +#define CHSC_SCSC_LEN 0x0010 + +bool get_chsc_scsc(void); + +#define CSS_GENERAL_FEAT_BITLEN (255 * 64) +#define CSS_CHSC_FEAT_BITLEN (254 * 64) + +#define CHSC_SCSC 0x0010 +#define CHSC_SCSC_LEN 0x0010 + +#define CHSC_ERROR 0x0000 +#define CHSC_RSP_OK 0x0001 +#define CHSC_RSP_INVAL 0x0002 +#define CHSC_RSP_REQERR 0x0003 +#define CHSC_RSP_ENOCMD 0x0004 +#define CHSC_RSP_NODATA 0x0005 +#define CHSC_RSP_SUP31B 0x0006 +#define CHSC_RSP_EFRMT 0x0007 +#define CHSC_RSP_ECSSID 0x0008 +#define CHSC_RSP_ERFRMT 0x0009 +#define CHSC_RSP_ESSID 0x000A +#define CHSC_RSP_EBUSY 0x000B +#define CHSC_RSP_MAX 0x000B + +static inline int _chsc(void *p) +{ + int cc; + + asm volatile(" .insn rre,0xb25f0000,%2,0\n" + " ipm %0\n" + " srl %0,28\n" + : "=d" (cc), "=m" (p) + : "d" (p), "m" (p) + : "cc"); + + return cc; +} + +bool chsc(void *p, uint16_t code, uint16_t len); + +#include <bitops.h> +#define css_test_general_feature(bit) test_bit_inv(bit, chsc_scsc->general_char) +#define css_test_chsc_feature(bit) test_bit_inv(bit, chsc_scsc->chsc_char) + #endif diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c index 3c244801..3c1acbfb 100644 --- a/lib/s390x/css_lib.c +++ b/lib/s390x/css_lib.c @@ -15,11 +15,102 @@ #include <asm/arch_def.h> #include <asm/time.h> #include <asm/arch_def.h> - +#include <alloc_page.h> #include <malloc_io.h> #include <css.h> static struct schib schib; +struct chsc_scsc *chsc_scsc; + +static const char * const chsc_rsp_description[] = { + "CHSC unknown error", + "Command executed", + "Invalid command", + "Request-block error", + "Command not installed", + "Data not available", + "Absolute address of channel-subsystem communication block exceeds 2G - 1.", + "Invalid command format", + "Invalid channel-subsystem identification (CSSID)", + "The command-request block specified an invalid format for the command response block.", + "Invalid subchannel-set identification (SSID)", + "A busy condition precludes execution.", +}; + +static bool check_response(void *p) +{ + struct chsc_header *h = p; + + if (h->code == CHSC_RSP_OK) + return true; + + if (h->code > CHSC_RSP_MAX) + h->code = 0; + + report_abort("Response code %04x: %s", h->code, + chsc_rsp_description[h->code]); + return false; +} + +bool chsc(void *p, uint16_t code, uint16_t len) +{ + struct chsc_header *h = p; + + h->code = code; + h->len = len; + + switch (_chsc(p)) { + case 3: + report_abort("Subchannel invalid or not enabled."); + break; + case 2: + report_abort("CHSC subchannel busy."); + break; + case 1: + report_abort("Subchannel invalid or not enabled."); + break; + case 0: + return check_response(p + len); + } + return false; +} + +bool get_chsc_scsc(void) +{ + int i, n; + char buffer[510]; + char *p; + + if (chsc_scsc) /* chsc_scsc already initialized */ + return true; + + chsc_scsc = alloc_page(); + if (!chsc_scsc) { + report_abort("could not allocate chsc_scsc page!"); + return false; + } + + if (!chsc(chsc_scsc, CHSC_SCSC, CHSC_SCSC_LEN)) + return false; + + for (i = 0, p = buffer; i < CSS_GENERAL_FEAT_BITLEN; i++) { + if (css_test_general_feature(i)) { + n = snprintf(p, sizeof(buffer), "%d,", i); + p += n; + } + } + report_info("General features: %s", buffer); + + for (i = 0, p = buffer; i < CSS_CHSC_FEAT_BITLEN; i++) { + if (css_test_chsc_feature(i)) { + n = snprintf(p, sizeof(buffer), "%d,", i); + p += n; + } + } + report_info("CHSC features: %s", buffer); + + return true; +} /* * css_enumerate: diff --git a/s390x/css.c b/s390x/css.c index 1a61a5c2..12036b3b 100644 --- a/s390x/css.c +++ b/s390x/css.c @@ -14,6 +14,7 @@ #include <string.h> #include <interrupt.h> #include <asm/arch_def.h> +#include <alloc_page.h> #include <malloc_io.h> #include <css.h> @@ -140,10 +141,17 @@ error_senseid: unregister_io_int_func(css_irq_io); } +static void css_init(void) +{ + report(get_chsc_scsc(), "Store Channel Characteristics"); +} + static struct { const char *name; void (*func)(void); } tests[] = { + /* The css_init test is needed to initialize the CSS Characteristics */ + { "initialize CSS (chsc)", css_init }, { "enumerate (stsch)", test_enumerate }, { "enable (msch)", test_enable }, { "sense (ssch/tsch)", test_sense }, -- 2.30.2
