[PATCH] s390: export ipl device parameters

Sysfs interface to export ipl device parameters.  Dependent on the ipl type
the interface will look like this:

- ccw ipl:

/sys/firmware/ipl/device
		 /ipl_type

- fcp ipl:

/sys/firmware/ipl/binary_parameter
		 /bootprog
		 /br_lba
		 /device
		 /ipl_type
		 /lun
		 /scp_data
		 /wwpn

- otherwise (unknown that is):

/sys/firmware/ipl/ipl_type

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 317 insertions, 7 deletions

diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S
index 55654b6e16dc..039354d72348 100644
--- a/arch/s390/kernel/head.S
+++ b/arch/s390/kernel/head.S
@@ -485,7 +485,9 @@ start:
 #
         .org  0x10000
 startup:basr  %r13,0                     # get base
-.LPG1:  lctl  %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
+.LPG1:  l     %r1, .Lget_ipl_device_addr-.LPG1(%r13)
+        basr  %r14, %r1
+        lctl  %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
         la    %r12,_pstart-.LPG1(%r13)   # pointer to parameter area
                                          # move IPL device to lowcore
         mvc   __LC_IPLDEV(4),IPL_DEVICE-PARMAREA(%r12)
@@ -560,6 +562,9 @@ startup:basr  %r13,0                     # get base
         mr    %r2,%r1                   # mem size in bytes in %r3
         b     .Lfchunk-.LPG1(%r13)
 
+        .align 4
+.Lget_ipl_device_addr:
+        .long .Lget_ipl_device
 .Lpmask:
         .byte 0
 .align 8
@@ -755,6 +760,63 @@ _pstart:
         .global _pend
 _pend:  
 
+.Lget_ipl_device:
+        basr  %r12,0
+.LPG2:  l     %r1,0xb8                  # get sid
+        sll   %r1,15                    # test if subchannel is enabled
+        srl   %r1,31
+        ltr   %r1,%r1
+        bz    0(%r14)                   # subchannel disabled
+        l     %r1,0xb8
+        la    %r5,.Lipl_schib-.LPG2(%r12)
+        stsch 0(%r5)                    # get schib of subchannel
+        bnz   0(%r14)                   # schib not available
+        tm    5(%r5),0x01               # devno valid?
+        bno   0(%r14)
+        la    %r6,ipl_parameter_flags-.LPG2(%r12)
+        oi    3(%r6),0x01               # set flag
+        la    %r2,ipl_devno-.LPG2(%r12)
+        mvc   0(2,%r2),6(%r5)           # store devno
+        tm    4(%r5),0x80               # qdio capable device?
+        bno   0(%r14)
+        oi    3(%r6),0x02               # set flag
+
+        # copy ipl parameters
+
+        lhi   %r0,4096
+        l     %r2,20(%r0)               # get address of parameter list
+        lhi   %r3,IPL_PARMBLOCK_ORIGIN
+        st    %r3,20(%r0)
+        lhi   %r4,1
+        cr    %r2,%r3                   # start parameters < destination ?
+        jl    0f
+        lhi   %r1,1                     # copy direction is upwards
+        j     1f
+0:      lhi   %r1,-1                    # copy direction is downwards
+        ar    %r2,%r0
+        ar    %r3,%r0
+        ar    %r2,%r1
+        ar    %r3,%r1
+1:      mvc   0(1,%r3),0(%r2)           # finally copy ipl parameters
+        ar    %r3,%r1
+        ar    %r2,%r1
+        sr    %r0,%r4
+        jne   1b
+        b     0(%r14)
+
+        .align 4
+.Lipl_schib:
+        .rept 13
+        .long 0
+        .endr
+
+        .globl ipl_parameter_flags
+ipl_parameter_flags:
+        .long 0
+        .globl ipl_devno
+ipl_devno:
+        .word 0
+
 #ifdef CONFIG_SHARED_KERNEL
         .org   0x100000
 #endif
@@ -764,11 +826,11 @@ _pend:
 #
         .globl _stext
 _stext: basr  %r13,0                    # get base
-.LPG2:
+.LPG3:
 #
 # Setup stack
 #
-        l     %r15,.Linittu-.LPG2(%r13)
+        l     %r15,.Linittu-.LPG3(%r13)
         mvc   __LC_CURRENT(4),__TI_task(%r15)
         ahi   %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
         st    %r15,__LC_KERNEL_STACK    # set end of kernel stack
@@ -782,8 +844,8 @@ _stext:	basr  %r13,0                    # get base
         lctl   %c0,%c15,0(%r15)
 
 #
-        lam    0,15,.Laregs-.LPG2(%r13) # load access regs needed by uaccess
-        l      %r14,.Lstart-.LPG2(%r13)
+        lam    0,15,.Laregs-.LPG3(%r13) # load access regs needed by uaccess
+        l      %r14,.Lstart-.LPG3(%r13)
         basr   %r14,%r14                # call start_kernel
 #
 # We returned from start_kernel ?!? PANIK
diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S
index c9ff0404c875..193aafa72f54 100644
--- a/arch/s390/kernel/head64.S
+++ b/arch/s390/kernel/head64.S
@@ -484,6 +484,8 @@ start:
 startup:basr  %r13,0                     # get base
 .LPG1:  sll   %r13,1                     # remove high order bit
         srl   %r13,1
+        l     %r1,.Lget_ipl_device_addr-.LPG1(%r13)
+        basr  %r14,%r1
         lhi   %r1,1                      # mode 1 = esame
         slr   %r0,%r0                    # set cpuid to zero
         sigp  %r1,%r0,0x12               # switch to esame mode
@@ -556,6 +558,9 @@ startup:basr  %r13,0                     # get base
         mlgr  %r2,%r1                   # mem size in bytes in %r3
         b     .Lfchunk-.LPG1(%r13)
 
+        .align 4
+.Lget_ipl_device_addr:
+        .long .Lget_ipl_device
 .Lpmask:
         .byte 0
         .align 8
@@ -746,6 +751,63 @@ _pstart:
         .global _pend
 _pend:  
 
+.Lget_ipl_device:
+        basr  %r12,0
+.LPG2:  l     %r1,0xb8                  # get sid
+        sll   %r1,15                    # test if subchannel is enabled
+        srl   %r1,31
+        ltr   %r1,%r1
+        bz    0(%r14)                   # subchannel disabled
+        l     %r1,0xb8
+        la    %r5,.Lipl_schib-.LPG2(%r12)
+        stsch 0(%r5)                    # get schib of subchannel
+        bnz   0(%r14)                   # schib not available
+        tm    5(%r5),0x01               # devno valid?
+        bno   0(%r14)
+        la    %r6,ipl_parameter_flags-.LPG2(%r12)
+        oi    3(%r6),0x01               # set flag
+        la    %r2,ipl_devno-.LPG2(%r12)
+        mvc   0(2,%r2),6(%r5)           # store devno
+        tm    4(%r5),0x80               # qdio capable device?
+        bno   0(%r14)
+        oi    3(%r6),0x02               # set flag
+
+        # copy ipl parameters
+
+        lhi   %r0,4096
+        l     %r2,20(%r0)               # get address of parameter list
+        lhi   %r3,IPL_PARMBLOCK_ORIGIN
+        st    %r3,20(%r0)
+        lhi   %r4,1
+        cr    %r2,%r3                   # start parameters < destination ?
+        jl    0f
+        lhi   %r1,1                     # copy direction is upwards
+        j     1f
+0:      lhi   %r1,-1                    # copy direction is downwards
+        ar    %r2,%r0
+        ar    %r3,%r0
+        ar    %r2,%r1
+        ar    %r3,%r1
+1:      mvc   0(1,%r3),0(%r2)           # finally copy ipl parameters
+        ar    %r3,%r1
+        ar    %r2,%r1
+        sr    %r0,%r4
+        jne   1b
+        b     0(%r14)
+
+        .align 4
+.Lipl_schib:
+        .rept 13
+        .long 0
+        .endr
+
+        .globl ipl_parameter_flags
+ipl_parameter_flags:
+        .long 0
+        .globl ipl_devno
+ipl_devno:
+        .word 0
+
 #ifdef CONFIG_SHARED_KERNEL
         .org   0x100000
 #endif
@@ -755,7 +817,7 @@ _pend:
 #
         .globl _stext
 _stext: basr  %r13,0                    # get base
-.LPG2:
+.LPG3:
 #
 # Setup stack
 #
@@ -774,7 +836,7 @@ _stext:	basr  %r13,0                    # get base
         lctlg  %c0,%c15,0(%r15)
 
 #
-        lam    0,15,.Laregs-.LPG2(%r13) # load access regs needed by uaccess
+        lam    0,15,.Laregs-.LPG3(%r13) # load access regs needed by uaccess
         brasl  %r14,start_kernel        # go to C code
 #
 # We returned from start_kernel ?!? PANIK
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 5204778b8e5e..31e7b19348b7 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -36,6 +36,7 @@
 #include <linux/console.h>
 #include <linux/seq_file.h>
 #include <linux/kernel_stat.h>
+#include <linux/device.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -685,3 +686,188 @@ struct seq_operations cpuinfo_op = {
         .show   = show_cpuinfo,
 };
 
+#define DEFINE_IPL_ATTR(_name, _format, _value)                 \
+static ssize_t ipl_##_name##_show(struct subsystem *subsys,     \
+                char *page)                                     \
+{                                                               \
+        return sprintf(page, _format, _value);                  \
+}                                                               \
+static struct subsys_attribute ipl_##_name##_attr =             \
+        __ATTR(_name, S_IRUGO, ipl_##_name##_show, NULL);
+
+DEFINE_IPL_ATTR(wwpn, "0x%016llx\n", (unsigned long long)
+                IPL_PARMBLOCK_START->fcp.wwpn);
+DEFINE_IPL_ATTR(lun, "0x%016llx\n", (unsigned long long)
+                IPL_PARMBLOCK_START->fcp.lun);
+DEFINE_IPL_ATTR(bootprog, "%lld\n", (unsigned long long)
+                IPL_PARMBLOCK_START->fcp.bootprog);
+DEFINE_IPL_ATTR(br_lba, "%lld\n", (unsigned long long)
+                IPL_PARMBLOCK_START->fcp.br_lba);
+
+enum ipl_type_type {
+        ipl_type_unknown,
+        ipl_type_ccw,
+        ipl_type_fcp,
+};
+
+static enum ipl_type_type
+get_ipl_type(void)
+{
+        struct ipl_parameter_block *ipl = IPL_PARMBLOCK_START;
+
+        if (!IPL_DEVNO_VALID)
+                return ipl_type_unknown;
+        if (!IPL_PARMBLOCK_VALID)
+                return ipl_type_ccw;
+        if (ipl->hdr.header.version > IPL_MAX_SUPPORTED_VERSION)
+                return ipl_type_unknown;
+        if (ipl->fcp.pbt != IPL_TYPE_FCP)
+                return ipl_type_unknown;
+        return ipl_type_fcp;
+}
+
+static ssize_t
+ipl_type_show(struct subsystem *subsys, char *page)
+{
+        switch (get_ipl_type()) {
+        case ipl_type_ccw:
+                return sprintf(page, "ccw\n");
+        case ipl_type_fcp:
+                return sprintf(page, "fcp\n");
+        default:
+                return sprintf(page, "unknown\n");
+        }
+}
+
+static struct subsys_attribute ipl_type_attr = __ATTR_RO(ipl_type);
+
+static ssize_t
+ipl_device_show(struct subsystem *subsys, char *page)
+{
+        struct ipl_parameter_block *ipl = IPL_PARMBLOCK_START;
+
+        switch (get_ipl_type()) {
+        case ipl_type_ccw:
+                return sprintf(page, "0.0.%04x\n", ipl_devno);
+        case ipl_type_fcp:
+                return sprintf(page, "0.0.%04x\n", ipl->fcp.devno);
+        default:
+                return 0;
+        }
+}
+
+static struct subsys_attribute ipl_device_attr =
+        __ATTR(device, S_IRUGO, ipl_device_show, NULL);
+
+static struct attribute *ipl_fcp_attrs[] = {
+        &ipl_type_attr.attr,
+        &ipl_device_attr.attr,
+        &ipl_wwpn_attr.attr,
+        &ipl_lun_attr.attr,
+        &ipl_bootprog_attr.attr,
+        &ipl_br_lba_attr.attr,
+        NULL,
+};
+
+static struct attribute_group ipl_fcp_attr_group = {
+        .attrs = ipl_fcp_attrs,
+};
+
+static struct attribute *ipl_ccw_attrs[] = {
+        &ipl_type_attr.attr,
+        &ipl_device_attr.attr,
+        NULL,
+};
+
+static struct attribute_group ipl_ccw_attr_group = {
+        .attrs = ipl_ccw_attrs,
+};
+
+static struct attribute *ipl_unknown_attrs[] = {
+        &ipl_type_attr.attr,
+        NULL,
+};
+
+static struct attribute_group ipl_unknown_attr_group = {
+        .attrs = ipl_unknown_attrs,
+};
+
+static ssize_t
+ipl_parameter_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
+{
+        unsigned int size = IPL_PARMBLOCK_SIZE;
+
+        if (off > size)
+                return 0;
+        if (off + count > size)
+                count = size - off;
+
+        memcpy(buf, (void *) IPL_PARMBLOCK_START + off, count);
+        return count;
+}
+
+static struct bin_attribute ipl_parameter_attr = {
+        .attr = {
+                .name = "binary_parameter",
+                .mode = S_IRUGO,
+                .owner = THIS_MODULE,
+        },
+        .size = PAGE_SIZE,
+        .read = &ipl_parameter_read,
+};
+
+static ssize_t
+ipl_scp_data_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
+{
+        unsigned int size =  IPL_PARMBLOCK_START->fcp.scp_data_len;
+        void *scp_data = &IPL_PARMBLOCK_START->fcp.scp_data;
+
+        if (off > size)
+                return 0;
+        if (off + count > size)
+                count = size - off;
+
+        memcpy(buf, scp_data + off, count);
+        return count;
+}
+
+static struct bin_attribute ipl_scp_data_attr = {
+        .attr = {
+                .name = "scp_data",
+                .mode = S_IRUGO,
+                .owner = THIS_MODULE,
+        },
+        .size = PAGE_SIZE,
+        .read = &ipl_scp_data_read,
+};
+
+static decl_subsys(ipl, NULL, NULL);
+
+static int __init
+ipl_device_sysfs_register(void) {
+        int rc;
+
+        rc = firmware_register(&ipl_subsys);
+        if (rc)
+                return rc;
+
+        switch (get_ipl_type()) {
+        case ipl_type_ccw:
+                sysfs_create_group(&ipl_subsys.kset.kobj, &ipl_ccw_attr_group);
+                break;
+        case ipl_type_fcp:
+                sysfs_create_group(&ipl_subsys.kset.kobj, &ipl_fcp_attr_group);
+                sysfs_create_bin_file(&ipl_subsys.kset.kobj,
+                                      &ipl_parameter_attr);
+                sysfs_create_bin_file(&ipl_subsys.kset.kobj,
+                                      &ipl_scp_data_attr);
+                break;
+        default:
+                sysfs_create_group(&ipl_subsys.kset.kobj,
+                                   &ipl_unknown_attr_group);
+                break;
+        }
+        return 0;
+}
+
+__initcall(ipl_device_sysfs_register);