pc-bios/s390-ccw: Use the libc from SLOF and remove sclp prints

We are already using the libc from SLOF for the s390-netboot.img, and
this libc implementation is way more complete and accurate than the
simple implementation that we currently use for the s390-ccw.img binary.
Since we are now always assuming that the SLOF submodule is available
when building the s390-ccw bios (see commit bf6903f6944f), we can drop
the simple implementation and use the SLOF libc for the s390-ccw.img
binary, too.

Additionally replace sclp_print calls with puts/printf now that it is
available.

Co-authored by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Message-ID: <20241020012953.1380075-3-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

17 files changed, 136 insertions, 335 deletions

diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile
index 6207911b53..3f4232636e 100644
--- a/pc-bios/s390-ccw/Makefile
+++ b/pc-bios/s390-ccw/Makefile
@@ -33,13 +33,18 @@ QEMU_DGFLAGS = -MMD -MP -MT $@ -MF $(@D)/$(*F).d
 .PHONY : all clean build-all distclean
 
 OBJECTS = start.o main.o bootmap.o jump2ipl.o sclp.o menu.o \
-	  virtio.o virtio-scsi.o virtio-blkdev.o libc.o cio.o dasd-ipl.o
+	  virtio.o virtio-scsi.o virtio-blkdev.o cio.o dasd-ipl.o
+
+SLOF_DIR := $(SRC_PATH)/../../roms/SLOF
+
+LIBC_INC := -nostdinc -I$(SLOF_DIR)/lib/libc/include
 
 EXTRA_CFLAGS += -Wall
 EXTRA_CFLAGS += -ffreestanding -fno-delete-null-pointer-checks -fno-common -fPIE
 EXTRA_CFLAGS += -fwrapv -fno-strict-aliasing -fno-asynchronous-unwind-tables
 EXTRA_CFLAGS += -msoft-float
 EXTRA_CFLAGS += -std=gnu99
+EXTRA_CFLAGS += $(LIBC_INC)
 LDFLAGS += -Wl,-pie -nostdlib -z noexecstack
 
 cc-test = $(CC) -Werror $1 -c -o /dev/null -xc /dev/null >/dev/null 2>/dev/null
@@ -55,18 +60,18 @@ config-cc.mak: Makefile
 	    $(call cc-option,-march=z900,-march=z10)) 3> config-cc.mak
 -include config-cc.mak
 
+include $(SRC_PATH)/netboot.mak
+
 build-all: s390-ccw.img s390-netboot.img
 
-s390-ccw.elf: $(OBJECTS)
-	$(call quiet-command,$(CC) $(LDFLAGS) -o $@ $(OBJECTS),Linking)
+s390-ccw.elf: $(OBJECTS) libc.a
+	$(call quiet-command,$(CC) $(LDFLAGS) -o $@ $^,Linking)
 
 s390-ccw.img: s390-ccw.elf
 	$(call quiet-command,$(STRIP) --strip-unneeded $< -o $@,Stripping $< into)
 
 $(OBJECTS): Makefile
 
-include $(SRC_PATH)/netboot.mak
-
 ALL_OBJS = $(sort $(OBJECTS) $(NETOBJS) $(LIBCOBJS) $(LIBNETOBJS))
 -include $(ALL_OBJS:%.o=%.d)
 
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index a2137449dc..3cc79706be 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -8,7 +8,8 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "s390-arch.h"
 #include "bootmap.h"
@@ -21,7 +22,7 @@
 
 #ifdef DEBUG_FALLBACK
 #define dputs(txt) \
-    do { sclp_print("zipl: " txt); } while (0)
+    do { printf("zipl: " txt); } while (0)
 #else
 #define dputs(fmt, ...) \
     do { } while (0)
@@ -270,7 +271,7 @@ static int eckd_get_boot_menu_index(block_number_t s1b_block_nr)
         prev_block_nr = cur_block_nr;
     }
 
-    sclp_print("No zipl boot menu data found. Booting default entry.");
+    printf("No zipl boot menu data found. Booting default entry.");
     return 0;
 }
 
@@ -338,22 +339,22 @@ static void ipl_eckd_cdl(void)
     block_number_t bmt_block_nr, s1b_block_nr;
 
     /* we have just read the block #0 and recognized it as "IPL1" */
-    sclp_print("CDL\n");
+    puts("CDL");
 
     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
     read_block(1, ipl2, "Cannot read IPL2 record at block 1");
 
     mbr = &ipl2->mbr;
     if (!magic_match(mbr, ZIPL_MAGIC)) {
-        sclp_print("No zIPL section in IPL2 record.\n");
+        puts("No zIPL section in IPL2 record.");
         return;
     }
     if (!block_size_ok(mbr->blockptr.xeckd.bptr.size)) {
-        sclp_print("Bad block size in zIPL section of IPL2 record.\n");
+        puts("Bad block size in zIPL section of IPL2 record.");
         return;
     }
     if (mbr->dev_type != DEV_TYPE_ECKD) {
-        sclp_print("Non-ECKD device type in zIPL section of IPL2 record.\n");
+        puts("Non-ECKD device type in zIPL section of IPL2 record.");
         return;
     }
 
@@ -366,11 +367,11 @@ static void ipl_eckd_cdl(void)
     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
     read_block(2, vlbl, "Cannot read Volume Label at block 2");
     if (!magic_match(vlbl->key, VOL1_MAGIC)) {
-        sclp_print("Invalid magic of volume label block.\n");
+        puts("Invalid magic of volume label block.");
         return;
     }
     if (!magic_match(vlbl->f.key, VOL1_MAGIC)) {
-        sclp_print("Invalid magic of volser block.\n");
+        puts("Invalid magic of volser block.");
         return;
     }
     print_volser(vlbl->f.volser);
@@ -384,8 +385,8 @@ static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
     LDL_VTOC *vlbl = (void *)sec; /* already read, 3rd block */
     char msg[4] = { '?', '.', '\n', '\0' };
 
-    sclp_print((mode == ECKD_CMS) ? "CMS" : "LDL");
-    sclp_print(" version ");
+    printf((mode == ECKD_CMS) ? "CMS" : "LDL");
+    printf(" version ");
     switch (vlbl->LDL_version) {
     case LDL1_VERSION:
         msg[0] = '1';
@@ -398,7 +399,7 @@ static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
         msg[1] = '?';
         break;
     }
-    sclp_print(msg);
+    printf("%s", msg);
     print_volser(vlbl->volser);
 }
 
@@ -419,7 +420,7 @@ static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
         if (!magic_match(ipl1->bip.magic, ZIPL_MAGIC)) {
             return; /* not applicable layout */
         }
-        sclp_print("unlabeled LDL.\n");
+        puts("unlabeled LDL.");
     }
     verify_boot_info(&ipl1->bip);
 
@@ -466,7 +467,7 @@ static void print_eckd_msg(void)
             *p-- = ' ';
         }
     }
-    sclp_print(msg);
+    printf("%s", msg);
 }
 
 static void ipl_eckd(void)
@@ -488,11 +489,11 @@ static void ipl_eckd(void)
     if (eckd_valid_address((ExtEckdBlockPtr *)&vlbl->f.br, 0)) {
         ldipl_bmt = eckd_find_bmt((ExtEckdBlockPtr *)&vlbl->f.br);
         if (ldipl_bmt) {
-            sclp_print("List-Directed\n");
+            puts("List-Directed");
             /* LD-IPL does not use the S1B bock, just make it NULL */
             run_eckd_boot_script(ldipl_bmt, NULL_BLOCK_NR);
             /* Only return in error, retry as CCW-IPL */
-            sclp_print("Retrying IPL ");
+            printf("Retrying IPL ");
             print_eckd_msg();
         }
         memset(sec, FREE_SPACE_FILLER, sizeof(sec));
@@ -634,7 +635,7 @@ static void ipl_scsi(void)
         return;
     }
 
-    sclp_print("Using SCSI scheme.\n");
+    puts("Using SCSI scheme.");
     debug_print_int("MBR Version", mbr->version_id);
     IPL_check(mbr->version_id == 1,
               "Unknown MBR layout version, assuming version 1");
@@ -743,7 +744,7 @@ static inline uint32_t iso_get_file_size(uint32_t load_rba)
             if (cur_record->file_flags & 0x2) {
                 /* Subdirectory */
                 if (level == ISO9660_MAX_DIR_DEPTH - 1) {
-                    sclp_print("ISO-9660 directory depth limit exceeded\n");
+                    puts("ISO-9660 directory depth limit exceeded");
                 } else {
                     level++;
                     sec_loc[level] = iso_733_to_u32(cur_record->ext_loc);
@@ -778,9 +779,9 @@ static void load_iso_bc_entry(IsoBcSection *load)
     if (real_size) {
         /* Round up blocks to load */
         blks_to_load = (real_size + ISO_SECTOR_SIZE - 1) / ISO_SECTOR_SIZE;
-        sclp_print("ISO boot image size verified\n");
+        puts("ISO boot image size verified");
     } else {
-        sclp_print("ISO boot image size could not be verified\n");
+        puts("ISO boot image size could not be verified");
     }
 
     read_iso_boot_image(bswap32(s.load_rba),
@@ -896,7 +897,7 @@ static void zipl_load_vblk(void)
     }
 
     if (blksize != VIRTIO_DASD_DEFAULT_BLOCK_SIZE) {
-        sclp_print("Using guessed DASD geometry.\n");
+        puts("Using guessed DASD geometry.");
         virtio_assume_eckd();
     }
     ipl_eckd();
@@ -909,7 +910,7 @@ static void zipl_load_vscsi(void)
         ipl_iso_el_torito();
     }
 
-    sclp_print("Using guessed DASD geometry.\n");
+    puts("Using guessed DASD geometry.");
     virtio_assume_eckd();
     ipl_eckd();
 }
@@ -944,5 +945,5 @@ void zipl_load(void)
         panic("\n! Unknown IPL device type !\n");
     }
 
-    sclp_print("zIPL load failed.\n");
+    puts("zIPL load failed.");
 }
diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
index d4690a88c2..4a7d8a91f1 100644
--- a/pc-bios/s390-ccw/bootmap.h
+++ b/pc-bios/s390-ccw/bootmap.h
@@ -336,9 +336,7 @@ static inline void print_volser(const void *volser)
 
     ebcdic_to_ascii((char *)volser, ascii, 6);
     ascii[6] = '\0';
-    sclp_print("VOLSER=[");
-    sclp_print(ascii);
-    sclp_print("]\n");
+    printf("VOLSER=[%s]\n", ascii);
 }
 
 static inline bool unused_space(const void *p, size_t size)
diff --git a/pc-bios/s390-ccw/cio.c b/pc-bios/s390-ccw/cio.c
index 83ca27ab41..7b09a38c96 100644
--- a/pc-bios/s390-ccw/cio.c
+++ b/pc-bios/s390-ccw/cio.c
@@ -11,7 +11,8 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "s390-arch.h"
 #include "helper.h"
@@ -90,9 +91,9 @@ static void print_eckd_dasd_sense_data(SenseDataEckdDasd *sd)
     char msgline[512];
 
     if (sd->config_info & 0x8000) {
-        sclp_print("Eckd Dasd Sense Data (fmt 24-bytes):\n");
+        puts("Eckd Dasd Sense Data (fmt 24-bytes):");
     } else {
-        sclp_print("Eckd Dasd Sense Data (fmt 32-bytes):\n");
+        puts("Eckd Dasd Sense Data (fmt 32-bytes):");
     }
 
     strcat(msgline, "    Sense Condition Flags :");
@@ -158,22 +159,21 @@ static void print_eckd_dasd_sense_data(SenseDataEckdDasd *sd)
     if (sd->status[1] & SNS_STAT2_IMPRECISE_END) {
         strcat(msgline, " [Imprecise-End]");
     }
-    strcat(msgline, "\n");
-    sclp_print(msgline);
-
-    print_int("    Residual Count     =", sd->res_count);
-    print_int("    Phys Drive ID      =", sd->phys_drive_id);
-    print_int("    low cyl address    =", sd->low_cyl_addr);
-    print_int("    head addr & hi cyl =", sd->head_high_cyl_addr);
-    print_int("    format/message     =", sd->fmt_msg);
-    print_int("    fmt-dependent[0-7] =", sd->fmt_dependent_info[0]);
-    print_int("    fmt-dependent[8-15]=", sd->fmt_dependent_info[1]);
-    print_int("    prog action code   =", sd->program_action_code);
-    print_int("    Configuration info =", sd->config_info);
-    print_int("    mcode / hi-cyl     =", sd->mcode_hicyl);
-    print_int("    cyl & head addr [0]=", sd->cyl_head_addr[0]);
-    print_int("    cyl & head addr [1]=", sd->cyl_head_addr[1]);
-    print_int("    cyl & head addr [2]=", sd->cyl_head_addr[2]);
+    puts(msgline);
+
+    printf("    Residual Count     = 0x%X\n", sd->res_count);
+    printf("    Phys Drive ID      = 0x%X\n", sd->phys_drive_id);
+    printf("    low cyl address    = 0x%X\n", sd->low_cyl_addr);
+    printf("    head addr & hi cyl = 0x%X\n", sd->head_high_cyl_addr);
+    printf("    format/message     = 0x%X\n", sd->fmt_msg);
+    printf("    fmt-dependent[0-7] = 0x%llX\n", sd->fmt_dependent_info[0]);
+    printf("    fmt-dependent[8-15]= 0x%llX\n", sd->fmt_dependent_info[1]);
+    printf("    prog action code   = 0x%X\n", sd->program_action_code);
+    printf("    Configuration info = 0x%X\n", sd->config_info);
+    printf("    mcode / hi-cyl     = 0x%X\n", sd->mcode_hicyl);
+    printf("    cyl & head addr [0]= 0x%X\n", sd->cyl_head_addr[0]);
+    printf("    cyl & head addr [1]= 0x%X\n", sd->cyl_head_addr[1]);
+    printf("    cyl & head addr [2]= 0x%X\n", sd->cyl_head_addr[2]);
 }
 
 static void print_irb_err(Irb *irb)
@@ -182,7 +182,7 @@ static void print_irb_err(Irb *irb)
     uint64_t prev_ccw = *(uint64_t *)u32toptr(irb->scsw.cpa - 8);
     char msgline[256];
 
-    sclp_print("Interrupt Response Block Data:\n");
+    puts("Interrupt Response Block Data:");
 
     strcat(msgline, "    Function Ctrl :");
     if (irb->scsw.ctrl & SCSW_FCTL_START_FUNC) {
@@ -194,8 +194,7 @@ static void print_irb_err(Irb *irb)
     if (irb->scsw.ctrl & SCSW_FCTL_CLEAR_FUNC) {
         strcat(msgline, " [Clear]");
     }
-    strcat(msgline, "\n");
-    sclp_print(msgline);
+    puts(msgline);
 
     msgline[0] = '\0';
     strcat(msgline, "    Activity Ctrl :");
@@ -220,8 +219,7 @@ static void print_irb_err(Irb *irb)
     if (irb->scsw.ctrl & SCSW_ACTL_SUSPENDED) {
         strcat(msgline, " [Suspended]");
     }
-    strcat(msgline, "\n");
-    sclp_print(msgline);
+    puts(msgline);
 
     msgline[0] = '\0';
     strcat(msgline, "    Status Ctrl :");
@@ -240,9 +238,7 @@ static void print_irb_err(Irb *irb)
     if (irb->scsw.ctrl & SCSW_SCTL_STATUS_PEND) {
         strcat(msgline, " [Status-Pending]");
     }
-
-    strcat(msgline, "\n");
-    sclp_print(msgline);
+    puts(msgline);
 
     msgline[0] = '\0';
     strcat(msgline, "    Device Status :");
@@ -270,8 +266,7 @@ static void print_irb_err(Irb *irb)
     if (irb->scsw.dstat & SCSW_DSTAT_UEXCP) {
         strcat(msgline, " [Unit-Exception]");
     }
-    strcat(msgline, "\n");
-    sclp_print(msgline);
+    puts(msgline);
 
     msgline[0] = '\0';
     strcat(msgline, "    Channel Status :");
@@ -299,12 +294,11 @@ static void print_irb_err(Irb *irb)
     if (irb->scsw.cstat & SCSW_CSTAT_CHAINCHK) {
         strcat(msgline, " [Chaining-Check]");
     }
-    strcat(msgline, "\n");
-    sclp_print(msgline);
+    puts(msgline);
 
-    print_int("    cpa=", irb->scsw.cpa);
-    print_int("    prev_ccw=", prev_ccw);
-    print_int("    this_ccw=", this_ccw);
+    printf("    cpa= 0x%X\n", irb->scsw.cpa);
+    printf("    prev_ccw= 0x%llX\n", prev_ccw);
+    printf("    this_ccw= 0x%llX\n", this_ccw);
 }
 
 /*
@@ -341,7 +335,7 @@ static int __do_cio(SubChannelId schid, uint32_t ccw_addr, int fmt, Irb *irb)
         return -1;
     }
     if (rc) {
-        print_int("ssch failed with cc=", rc);
+        printf("ssch failed with cc= 0x%x\n", rc);
         return rc;
     }
 
@@ -350,7 +344,7 @@ static int __do_cio(SubChannelId schid, uint32_t ccw_addr, int fmt, Irb *irb)
     /* collect status */
     rc = tsch(schid, irb);
     if (rc) {
-        print_int("tsch failed with cc=", rc);
+        printf("tsch failed with cc= 0x%X\n", rc);
     }
 
     return rc;
@@ -406,12 +400,12 @@ int do_cio(SubChannelId schid, uint16_t cutype, uint32_t ccw_addr, int fmt)
             continue;
         }
 
-        sclp_print("cio device error\n");
-        print_int("  ssid  ", schid.ssid);
-        print_int("  cssid ", schid.cssid);
-        print_int("  sch_no", schid.sch_no);
-        print_int("  ctrl-unit type", cutype);
-        sclp_print("\n");
+        printf("cio device error\n");
+        printf("  ssid  0x%X\n", schid.ssid);
+        printf("  cssid 0x%X\n", schid.cssid);
+        printf("  sch_no 0x%X\n", schid.sch_no);
+        printf("  ctrl-unit type 0x%X\n", cutype);
+        printf("\n");
         print_irb_err(&irb);
         if (cutype == CU_TYPE_DASD_3990 || cutype == CU_TYPE_DASD_2107 ||
             cutype == CU_TYPE_UNKNOWN) {
diff --git a/pc-bios/s390-ccw/dasd-ipl.c b/pc-bios/s390-ccw/dasd-ipl.c
index 254bb1a15e..ae751adec1 100644
--- a/pc-bios/s390-ccw/dasd-ipl.c
+++ b/pc-bios/s390-ccw/dasd-ipl.c
@@ -8,7 +8,8 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "s390-arch.h"
 #include "dasd-ipl.h"
@@ -82,7 +83,7 @@ static int run_dynamic_ccw_program(SubChannelId schid, uint16_t cutype,
     do {
         has_next = dynamic_cp_fixup(cpa, &next_cpa);
 
-        print_int("executing ccw chain at ", cpa);
+        printf("executing ccw chain at 0x%X\n", cpa);
         enable_prefixing();
         rc = do_cio(schid, cutype, cpa, CCW_FMT0);
         disable_prefixing();
diff --git a/pc-bios/s390-ccw/jump2ipl.c b/pc-bios/s390-ccw/jump2ipl.c
index 78f5f46533..80b7f6a1f3 100644
--- a/pc-bios/s390-ccw/jump2ipl.c
+++ b/pc-bios/s390-ccw/jump2ipl.c
@@ -6,7 +6,8 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "s390-arch.h"
 
@@ -57,7 +58,7 @@ void jump_to_IPL_code(uint64_t address)
     debug_print_int("set IPL addr to", address ?: *reset_psw & PSW_MASK_SHORT_ADDR);
 
     /* Ensure the guest output starts fresh */
-    sclp_print("\n");
+    printf("\n");
 
     /*
      * HACK ALERT.
diff --git a/pc-bios/s390-ccw/libc.c b/pc-bios/s390-ccw/libc.c
deleted file mode 100644
index 3187923950..0000000000
--- a/pc-bios/s390-ccw/libc.c
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * libc-style definitions and functions
- *
- * Copyright 2018 IBM Corp.
- * Author(s): Collin L. Walling <walling@linux.vnet.ibm.com>
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- */
-
-#include "libc.h"
-#include "s390-ccw.h"
-
-/**
- * atoui:
- * @str: the string to be converted.
- *
- * Given a string @str, convert it to an integer. Leading spaces are
- * ignored. Any other non-numerical value will terminate the conversion
- * and return 0. This function only handles numbers between 0 and
- * UINT64_MAX inclusive.
- *
- * Returns: an integer converted from the string @str, or the number 0
- * if an error occurred.
- */
-uint64_t atoui(const char *str)
-{
-    int val = 0;
-
-    if (!str || !str[0]) {
-        return 0;
-    }
-
-    while (*str == ' ') {
-        str++;
-    }
-
-    while (*str) {
-        if (!isdigit(*(unsigned char *)str)) {
-            break;
-        }
-        val = val * 10 + *str - '0';
-        str++;
-    }
-
-    return val;
-}
-
-/**
- * uitoa:
- * @num: an integer (base 10) to be converted.
- * @str: a pointer to a string to store the conversion.
- * @len: the length of the passed string.
- *
- * Given an integer @num, convert it to a string. The string @str must be
- * allocated beforehand. The resulting string will be null terminated and
- * returned. This function only handles numbers between 0 and UINT64_MAX
- * inclusive.
- *
- * Returns: the string @str of the converted integer @num
- */
-char *uitoa(uint64_t num, char *str, size_t len)
-{
-    long num_idx = 1; /* account for NUL */
-    uint64_t tmp = num;
-
-    IPL_assert(str != NULL, "uitoa: no space allocated to store string");
-
-    /* Count indices of num */
-    while ((tmp /= 10) != 0) {
-        num_idx++;
-    }
-
-    /* Check if we have enough space for num and NUL */
-    IPL_assert(len > num_idx, "uitoa: array too small for conversion");
-
-    str[num_idx--] = '\0';
-
-    /* Convert int to string */
-    while (num_idx >= 0) {
-        str[num_idx--] = num % 10 + '0';
-        num /= 10;
-    }
-
-    return str;
-}
diff --git a/pc-bios/s390-ccw/libc.h b/pc-bios/s390-ccw/libc.h
deleted file mode 100644
index bcdc45732d..0000000000
--- a/pc-bios/s390-ccw/libc.h
+++ /dev/null
@@ -1,89 +0,0 @@
-/*
- * libc-style definitions and functions
- *
- * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- */
-
-#ifndef S390_CCW_LIBC_H
-#define S390_CCW_LIBC_H
-
-typedef unsigned long      size_t;
-typedef int                bool;
-typedef unsigned char      uint8_t;
-typedef unsigned short     uint16_t;
-typedef unsigned int       uint32_t;
-typedef unsigned long long uint64_t;
-
-static inline void *memset(void *s, int c, size_t n)
-{
-    size_t i;
-    unsigned char *p = s;
-
-    for (i = 0; i < n; i++) {
-        p[i] = c;
-    }
-
-    return s;
-}
-
-static inline void *memcpy(void *s1, const void *s2, size_t n)
-{
-    uint8_t *dest = s1;
-    const uint8_t *src = s2;
-    size_t i;
-
-    for (i = 0; i < n; i++) {
-        dest[i] = src[i];
-    }
-
-    return s1;
-}
-
-static inline int memcmp(const void *s1, const void *s2, size_t n)
-{
-    size_t i;
-    const uint8_t *p1 = s1, *p2 = s2;
-
-    for (i = 0; i < n; i++) {
-        if (p1[i] != p2[i]) {
-            return p1[i] > p2[i] ? 1 : -1;
-        }
-    }
-
-    return 0;
-}
-
-static inline size_t strlen(const char *str)
-{
-    size_t i;
-    for (i = 0; *str; i++) {
-        str++;
-    }
-    return i;
-}
-
-static inline char *strcat(char *dest, const char *src)
-{
-    int i;
-    char *dest_end = dest + strlen(dest);
-
-    for (i = 0; i <= strlen(src); i++) {
-        dest_end[i] = src[i];
-    }
-    return dest;
-}
-
-static inline int isdigit(int c)
-{
-    return (c >= '0') && (c <= '9');
-}
-
-uint64_t atoui(const char *str);
-char *uitoa(uint64_t num, char *str, size_t len);
-
-#endif
diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index 5506798098..203df20965 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -8,7 +8,9 @@
  * directory.
  */
 
-#include "libc.h"
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
 #include "helper.h"
 #include "s390-arch.h"
 #include "s390-ccw.h"
@@ -50,7 +52,7 @@ void write_iplb_location(void)
 
 unsigned int get_loadparm_index(void)
 {
-    return atoui(loadparm_str);
+    return atoi(loadparm_str);
 }
 
 static int is_dev_possibly_bootable(int dev_no, int sch_no)
@@ -176,7 +178,7 @@ static void boot_setup(void)
 
     sclp_get_loadparm_ascii(loadparm_str);
     memcpy(lpmsg + 10, loadparm_str, 8);
-    sclp_print(lpmsg);
+    puts(lpmsg);
 
     /*
      * Clear out any potential S390EP magic (see jump_to_low_kernel()),
@@ -228,7 +230,7 @@ static int virtio_setup(void)
 
     switch (vdev->senseid.cu_model) {
     case VIRTIO_ID_NET:
-        sclp_print("Network boot device detected\n");
+        puts("Network boot device detected");
         vdev->netboot_start_addr = qipl.netboot_start_addr;
         return 0;
     case VIRTIO_ID_BLOCK:
@@ -261,7 +263,7 @@ static void ipl_boot_device(void)
         }
         break;
     default:
-        print_int("Attempting to boot from unexpected device type", cutype);
+        printf("Attempting to boot from unexpected device type 0x%X\n", cutype);
         panic("\nBoot failed.\n");
     }
 }
@@ -287,7 +289,7 @@ static void probe_boot_device(void)
         }
     }
 
-    sclp_print("Could not find a suitable boot device (none specified)\n");
+    puts("Could not find a suitable boot device (none specified)");
 }
 
 void main(void)
diff --git a/pc-bios/s390-ccw/menu.c b/pc-bios/s390-ccw/menu.c
index d601952d3e..84062e94af 100644
--- a/pc-bios/s390-ccw/menu.c
+++ b/pc-bios/s390-ccw/menu.c
@@ -9,7 +9,10 @@
  * directory.
  */
 
-#include "libc.h"
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include "s390-ccw.h"
 #include "sclp.h"
 #include "s390-time.h"
@@ -93,7 +96,7 @@ static int read_prompt(char *buf, size_t len)
         case KEYCODE_BACKSP:
             if (idx > 0) {
                 buf[--idx] = 0;
-                sclp_print("\b \b");
+                printf("\b \b");
             }
             continue;
         case KEYCODE_ENTER:
@@ -103,7 +106,7 @@ static int read_prompt(char *buf, size_t len)
             /* Echo input and add to buffer */
             if (idx < len) {
                 buf[idx++] = inp[0];
-                sclp_print(inp);
+                printf("%s", inp);
             }
         }
     }
@@ -140,22 +143,19 @@ static int get_index(void)
         }
     }
 
-    return atoui(buf);
+    return atoi(buf);
 }
 
 static void boot_menu_prompt(bool retry)
 {
-    char tmp[11];
-
     if (retry) {
-        sclp_print("\nError: undefined configuration"
+        printf("\nError: undefined configuration"
                    "\nPlease choose:\n");
     } else if (timeout > 0) {
-        sclp_print("Please choose (default will boot in ");
-        sclp_print(uitoa(timeout / 1000, tmp, sizeof(tmp)));
-        sclp_print(" seconds):\n");
+        printf("Please choose (default will boot in %d seconds):\n",
+               (int)(timeout / 1000));
     } else {
-        sclp_print("Please choose:\n");
+        puts("Please choose:");
     }
 }
 
@@ -163,7 +163,6 @@ static int get_boot_index(bool *valid_entries)
 {
     int boot_index;
     bool retry = false;
-    char tmp[5];
 
     do {
         boot_menu_prompt(retry);
@@ -172,8 +171,7 @@ static int get_boot_index(bool *valid_entries)
     } while (boot_index < 0 || boot_index >= MAX_BOOT_ENTRIES ||
              !valid_entries[boot_index]);
 
-    sclp_print("\nBooting entry #");
-    sclp_print(uitoa(boot_index, tmp, sizeof(tmp)));
+    printf("\nBooting entry #%d", boot_index);
 
     return boot_index;
 }
@@ -187,9 +185,9 @@ static int zipl_print_entry(const char *data, size_t len)
     buf[len] = '\n';
     buf[len + 1] = '\0';
 
-    sclp_print(buf);
+    printf("%s", buf);
 
-    return buf[0] == ' ' ? atoui(buf + 1) : atoui(buf);
+    return buf[0] == ' ' ? atoi(buf + 1) : atoi(buf);
 }
 
 int menu_get_zipl_boot_index(const char *menu_data)
@@ -209,7 +207,7 @@ int menu_get_zipl_boot_index(const char *menu_data)
     }
 
     /* Print banner */
-    sclp_print("s390-ccw zIPL Boot Menu\n\n");
+    puts("s390-ccw zIPL Boot Menu\n");
     menu_data += strlen(menu_data) + 1;
 
     /* Print entries */
@@ -221,37 +219,34 @@ int menu_get_zipl_boot_index(const char *menu_data)
         valid_entries[entry] = true;
 
         if (entry == 0) {
-            sclp_print("\n");
+            printf("\n");
         }
     }
 
-    sclp_print("\n");
+    printf("\n");
     return get_boot_index(valid_entries);
 }
 
 int menu_get_enum_boot_index(bool *valid_entries)
 {
-    char tmp[3];
     int i;
 
-    sclp_print("s390-ccw Enumerated Boot Menu.\n\n");
+    puts("s390-ccw Enumerated Boot Menu.\n");
 
     for (i = 0; i < MAX_BOOT_ENTRIES; i++) {
         if (valid_entries[i]) {
             if (i < 10) {
-                sclp_print(" ");
+                printf(" ");
             }
-            sclp_print("[");
-            sclp_print(uitoa(i, tmp, sizeof(tmp)));
-            sclp_print("]");
+            printf("[%d]", i);
             if (i == 0) {
-                sclp_print(" default\n");
+                printf(" default\n");
             }
-            sclp_print("\n");
+            printf("\n");
         }
     }
 
-    sclp_print("\n");
+    printf("\n");
     return get_boot_index(valid_entries);
 }
 
diff --git a/pc-bios/s390-ccw/netboot.mak b/pc-bios/s390-ccw/netboot.mak
index 046aa35587..d2b3d8ee74 100644
--- a/pc-bios/s390-ccw/netboot.mak
+++ b/pc-bios/s390-ccw/netboot.mak
@@ -1,9 +1,6 @@
 
-SLOF_DIR := $(SRC_PATH)/../../roms/SLOF
-
 NETOBJS := start.o sclp.o cio.o virtio.o virtio-net.o jump2ipl.o netmain.o
 
-LIBC_INC := -nostdinc -I$(SLOF_DIR)/lib/libc/include
 LIBNET_INC := -I$(SLOF_DIR)/lib/libnet
 
 NETLDFLAGS := $(LDFLAGS) -Wl,-Ttext=0x7800000
diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index 5cd619b2d6..509119be15 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -293,7 +293,7 @@ static int load_kernel_with_initrd(filename_ip_t *fn_ip,
     printf("Loading pxelinux.cfg entry '%s'\n", entry->label);
 
     if (!entry->kernel) {
-        printf("Kernel entry is missing!\n");
+        puts("Kernel entry is missing!\n");
         return -1;
     }
 
@@ -515,13 +515,13 @@ void main(void)
     int rc, fnlen;
 
     sclp_setup();
-    sclp_print("Network boot starting...\n");
+    puts("Network boot starting...");
 
     virtio_setup();
 
     rc = net_init(&fn_ip);
     if (rc) {
-        panic("Network initialization failed. Halting.\n");
+        panic("Network initialization failed. Halting.");
     }
 
     fnlen = strlen(fn_ip.filename);
@@ -535,9 +535,9 @@ void main(void)
     net_release(&fn_ip);
 
     if (rc > 0) {
-        sclp_print("Network loading done, starting kernel...\n");
+        puts("Network loading done, starting kernel...");
         jump_to_low_kernel();
     }
 
-    panic("Failed to load OS from network\n");
+    panic("Failed to load OS from network.");
 }
diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
index c977a52b50..6f6d95d170 100644
--- a/pc-bios/s390-ccw/s390-ccw.h
+++ b/pc-bios/s390-ccw/s390-ccw.h
@@ -13,6 +13,11 @@
 
 /* #define DEBUG */
 
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
 typedef unsigned char      u8;
 typedef unsigned short     u16;
 typedef unsigned int       u32;
@@ -26,9 +31,6 @@ typedef unsigned long long u64;
 #define EBUSY   2
 #define ENODEV  3
 
-#ifndef NULL
-#define NULL    0
-#endif
 #ifndef MIN
 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
 #endif
@@ -87,7 +89,7 @@ bool menu_is_enabled_enum(void);
 __attribute__ ((__noreturn__))
 static inline void panic(const char *string)
 {
-    sclp_print(string);
+    printf("ERROR: %s\n ", string);
     disabled_wait();
 }
 
@@ -109,20 +111,10 @@ static inline void fill_hex_val(char *out, void *ptr, unsigned size)
     }
 }
 
-static inline void print_int(const char *desc, u64 addr)
-{
-    char out[] = ": 0xffffffffffffffff\n";
-
-    fill_hex_val(&out[4], &addr, sizeof(addr));
-
-    sclp_print(desc);
-    sclp_print(out);
-}
-
 static inline void debug_print_int(const char *desc, u64 addr)
 {
 #ifdef DEBUG
-    print_int(desc, addr);
+    printf("%s 0x%X\n", desc, addr);
 #endif
 }
 
@@ -147,18 +139,14 @@ static inline void debug_print_addr(const char *desc, void *p)
 static inline void IPL_assert(bool term, const char *message)
 {
     if (!term) {
-        sclp_print("\n! ");
-        sclp_print(message);
-        panic(" !\n"); /* no return */
+        panic(message); /* no return */
     }
 }
 
 static inline void IPL_check(bool term, const char *message)
 {
     if (!term) {
-        sclp_print("\n! WARNING: ");
-        sclp_print(message);
-        sclp_print(" !\n");
+        printf("WARNING: %s\n", message);
     }
 }
 
diff --git a/pc-bios/s390-ccw/sclp.c b/pc-bios/s390-ccw/sclp.c
index 7251f9af4d..4a07de018d 100644
--- a/pc-bios/s390-ccw/sclp.c
+++ b/pc-bios/s390-ccw/sclp.c
@@ -8,7 +8,7 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
 #include "s390-ccw.h"
 #include "sclp.h"
 
@@ -101,11 +101,6 @@ long write(int fd, const void *str, size_t len)
     return len;
 }
 
-void sclp_print(const char *str)
-{
-    write(1, str, strlen(str));
-}
-
 void sclp_get_loadparm_ascii(char *loadparm)
 {
 
diff --git a/pc-bios/s390-ccw/virtio-blkdev.c b/pc-bios/s390-ccw/virtio-blkdev.c
index a81207b52e..2666326801 100644
--- a/pc-bios/s390-ccw/virtio-blkdev.c
+++ b/pc-bios/s390-ccw/virtio-blkdev.c
@@ -8,7 +8,7 @@
  * directory.
  */
 
-#include "libc.h"
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "virtio.h"
 #include "virtio-scsi.h"
@@ -76,7 +76,7 @@ unsigned long virtio_load_direct(unsigned long rec_list1, unsigned long rec_list
         return -1;
     }
 
-    sclp_print(".");
+    printf(".");
     status = virtio_read_many(sec, (void *)addr, sec_num);
     if (status) {
         panic("I/O Error");
@@ -230,7 +230,7 @@ int virtio_blk_setup_device(SubChannelId schid)
     vdev->schid = schid;
     virtio_setup_ccw(vdev);
 
-    sclp_print("Using virtio-blk.\n");
+    puts("Using virtio-blk.");
 
     return 0;
 }
diff --git a/pc-bios/s390-ccw/virtio-scsi.c b/pc-bios/s390-ccw/virtio-scsi.c
index d1a84b937c..6b4a1caf8a 100644
--- a/pc-bios/s390-ccw/virtio-scsi.c
+++ b/pc-bios/s390-ccw/virtio-scsi.c
@@ -9,7 +9,8 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
+#include <stdio.h>
 #include "s390-ccw.h"
 #include "virtio.h"
 #include "scsi.h"
@@ -30,9 +31,9 @@ static inline void vs_assert(bool term, const char **msgs)
     if (!term) {
         int i = 0;
 
-        sclp_print("\n! ");
+        printf("\n! ");
         while (msgs[i]) {
-            sclp_print(msgs[i++]);
+            printf("%s", msgs[i++]);
         }
         panic(" !\n");
     }
@@ -236,11 +237,11 @@ static int virtio_scsi_locate_device(VDev *vdev)
             if (resp.response == VIRTIO_SCSI_S_BAD_TARGET) {
                 continue;
             }
-            print_int("target", target);
+            printf("target 0x%X\n", target);
             virtio_scsi_verify_response(&resp, "SCSI cannot report LUNs");
         }
         if (r->lun_list_len == 0) {
-            print_int("no LUNs for target", target);
+            printf("no LUNs for target 0x%X\n", target);
             continue;
         }
         luns = r->lun_list_len / 8;
@@ -264,7 +265,7 @@ static int virtio_scsi_locate_device(VDev *vdev)
         }
     }
 
-    sclp_print("Warning: Could not locate a usable virtio-scsi device\n");
+    puts("Warning: Could not locate a usable virtio-scsi device");
     return -ENODEV;
 }
 
@@ -379,7 +380,7 @@ static int virtio_scsi_setup(VDev *vdev)
     }
 
     if (virtio_scsi_inquiry_response_is_cdrom(scsi_inquiry_std_response)) {
-        sclp_print("SCSI CD-ROM detected.\n");
+        puts("SCSI CD-ROM detected.");
         vdev->is_cdrom = true;
         vdev->scsi_block_size = VIRTIO_ISO_BLOCK_SIZE;
     }
@@ -443,7 +444,7 @@ int virtio_scsi_setup_device(SubChannelId schid)
     IPL_assert(vdev->config.scsi.cdb_size == VIRTIO_SCSI_CDB_SIZE,
                "Config: CDB size mismatch");
 
-    sclp_print("Using virtio-scsi.\n");
+    puts("Using virtio-scsi.");
 
     return virtio_scsi_setup(vdev);
 }
diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index 5edd058d88..8c6b0a8a92 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -8,7 +8,7 @@
  * directory.
  */
 
-#include "libc.h"
+#include <string.h>
 #include "s390-ccw.h"
 #include "cio.h"
 #include "virtio.h"