ColdFire: Move m5271evb from board to board/freescale

Signed-off-by: TsiChung Liew <Tsi-Chung.Liew@freescale.com>

5 files changed, 639 insertions, 0 deletions

diff --git a/board/freescale/m5271evb/Makefile b/board/freescale/m5271evb/Makefile
new file mode 100644
index 0000000000..2ec71ee1d2
--- /dev/null
+++ b/board/freescale/m5271evb/Makefile
@@ -0,0 +1,44 @@
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program 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.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+include $(TOPDIR)/config.mk
+
+LIB	= $(obj)lib$(BOARD).a
+
+COBJS	= $(BOARD).o mii.o
+
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+SOBJS	:= $(addprefix $(obj),$(SOBJS))
+
+$(LIB):	$(obj).depend $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/board/freescale/m5271evb/config.mk b/board/freescale/m5271evb/config.mk
new file mode 100644
index 0000000000..9a7af7c2c6
--- /dev/null
+++ b/board/freescale/m5271evb/config.mk
@@ -0,0 +1,25 @@
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+# Coldfire contribution by Bernhard Kuhn <bkuhn@metrowerks.com>
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program 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.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+TEXT_BASE = 0xffe00000
diff --git a/board/freescale/m5271evb/m5271evb.c b/board/freescale/m5271evb/m5271evb.c
new file mode 100644
index 0000000000..e089d5f02f
--- /dev/null
+++ b/board/freescale/m5271evb/m5271evb.c
@@ -0,0 +1,123 @@
+/*
+ * (C) Copyright 2000-2006
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/immap.h>
+
+int checkboard (void) {
+	puts ("Board: Freescale M5271EVB\n");
+	return 0;
+};
+
+phys_size_t initdram (int board_type) {
+
+	int i;
+
+	/* Enable Address lines 23-21 and lower 16bits of data path */
+	mbar_writeByte(MCF_GPIO_PAR_AD, MCF_GPIO_AD_ADDR23 |
+			MCF_GPIO_AD_ADDR22 | MCF_GPIO_AD_ADDR21 |
+			MCF_GPIO_AD_DATAL);
+
+	/* Set CS2 pin to be SD_CS0 */
+	mbar_writeByte(MCF_GPIO_PAR_CS, mbar_readByte(MCF_GPIO_PAR_CS)
+			| MCF_GPIO_PAR_CS_PAR_CS2);
+
+	/* Configure SDRAM Control Pin Assignemnt Register */
+	mbar_writeByte(MCF_GPIO_PAR_SDRAM, MCF_GPIO_SDRAM_CSSDCS_00 |
+			MCF_GPIO_SDRAM_SDWE | MCF_GPIO_SDRAM_SCAS |
+			MCF_GPIO_SDRAM_SRAS | MCF_GPIO_SDRAM_SCKE |
+			MCF_GPIO_SDRAM_SDCS_11);
+
+	/*
+	 * Check to see if the SDRAM has already been initialized
+	 * by a run control tool
+	 */
+	if (!(mbar_readLong(MCF_SDRAMC_DACR0) & MCF_SDRAMC_DACRn_RE)) {
+		/* Initialize DRAM Control Register: DCR */
+		mbar_writeShort(MCF_SDRAMC_DCR,
+				MCF_SDRAMC_DCR_RTIM(0x01)
+				| MCF_SDRAMC_DCR_RC(0x30));
+
+		/*
+		 * Initialize DACR0
+		 *
+		 * CASL: 01
+		 * CBM: cmd at A20, bank select bits 21 and up
+		 * PS: 32bit port size
+		 */
+		mbar_writeLong(MCF_SDRAMC_DACR0,
+				MCF_SDRAMC_DACRn_BA(CFG_SDRAM_BASE>>18)
+				| MCF_SDRAMC_DACRn_CASL(1)
+				| MCF_SDRAMC_DACRn_CBM(3)
+				| MCF_SDRAMC_DACRn_PS(0));
+
+		/* Initialize DMR0 */
+		mbar_writeLong(MCF_SDRAMC_DMR0,
+				MCF_SDRAMC_DMRn_BAM_16M
+				| MCF_SDRAMC_DMRn_V);
+
+		/* Set IP bit in DACR */
+		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
+				| MCF_SDRAMC_DACRn_IP);
+
+		/* Wait at least 20ns to allow banks to precharge */
+		for (i = 0; i < 5; i++)
+			asm(" nop");
+
+		/* Write to this block to initiate precharge */
+		*(u32 *)(CFG_SDRAM_BASE) = 0xa5a5a5a5;
+
+		/* Set RE bit in DACR */
+		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
+				| MCF_SDRAMC_DACRn_RE);
+
+		/* Wait for at least 8 auto refresh cycles to occur */
+		for (i = 0; i < 2000; i++)
+			asm(" nop");
+
+		/* Finish the configuration by issuing the MRS */
+		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
+				| MCF_SDRAMC_DACRn_MRS);
+
+		/*
+		 * Write to the SDRAM Mode Register A0-A11 = 0x400
+		 *
+		 * Write Burst Mode = Programmed Burst Length
+		 * Op Mode = Standard Op
+		 * CAS Latency = 2
+		 * Burst Type = Sequential
+		 * Burst Length = 1
+		 */
+		*(u32 *)(CFG_SDRAM_BASE + 0x400) = 0xa5a5a5a5;
+	}
+
+	return CFG_SDRAM_SIZE * 1024 * 1024;
+};
+
+int testdram (void) {
+
+	/* TODO: XXX XXX XXX */
+	printf ("DRAM test not implemented!\n");
+
+	return (0);
+}
diff --git a/board/freescale/m5271evb/mii.c b/board/freescale/m5271evb/mii.c
new file mode 100644
index 0000000000..78a7028bcf
--- /dev/null
+++ b/board/freescale/m5271evb/mii.c
@@ -0,0 +1,303 @@
+/*
+ * Copyright (C) 2004-2007 Freescale Semiconductor, Inc.
+ * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/fec.h>
+#include <asm/immap.h>
+
+#include <config.h>
+#include <net.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#if defined(CONFIG_CMD_NET) && defined(CONFIG_NET_MULTI)
+#undef MII_DEBUG
+#undef ET_DEBUG
+
+int fecpin_setclear(struct eth_device *dev, int setclear)
+{
+	if (setclear) {
+		/* Enable Ethernet pins */
+		mbar_writeByte(MCF_GPIO_PAR_FECI2C, CFG_FECI2C);
+	} else {
+	}
+
+	return 0;
+}
+
+#if defined(CFG_DISCOVER_PHY) || defined(CONFIG_CMD_MII)
+#include <miiphy.h>
+
+/* Make MII read/write commands for the FEC. */
+#define mk_mii_read(ADDR, REG)	(0x60020000 | ((ADDR << 23) | (REG & 0x1f) << 18))
+
+#define mk_mii_write(ADDR, REG, VAL)	(0x50020000 | ((ADDR << 23) | (REG & 0x1f) << 18) | (VAL & 0xffff))
+
+/* PHY identification */
+#define PHY_ID_LXT970		0x78100000	/* LXT970 */
+#define PHY_ID_LXT971		0x001378e0	/* LXT971 and 972 */
+#define PHY_ID_82555		0x02a80150	/* Intel 82555 */
+#define PHY_ID_QS6612		0x01814400	/* QS6612 */
+#define PHY_ID_AMD79C784	0x00225610	/* AMD 79C784 */
+#define PHY_ID_LSI80225		0x0016f870	/* LSI 80225 */
+#define PHY_ID_LSI80225B	0x0016f880	/* LSI 80225/B */
+#define PHY_ID_DP83848VV	0x20005C90	/* National 83848 */
+#define PHY_ID_DP83849		0x20005CA2	/* National 82849 */
+#define PHY_ID_KS8721BL		0x00221619	/* Micrel KS8721BL/SL */
+
+#define STR_ID_LXT970		"LXT970"
+#define STR_ID_LXT971		"LXT971"
+#define STR_ID_82555		"Intel82555"
+#define STR_ID_QS6612		"QS6612"
+#define STR_ID_AMD79C784	"AMD79C784"
+#define STR_ID_LSI80225		"LSI80225"
+#define STR_ID_LSI80225B	"LSI80225/B"
+#define STR_ID_DP83848VV	"N83848"
+#define STR_ID_DP83849		"N83849"
+#define STR_ID_KS8721BL		"KS8721BL"
+
+/****************************************************************************
+ * mii_init -- Initialize the MII for MII command without ethernet
+ * This function is a subset of eth_init
+ ****************************************************************************
+ */
+void mii_reset(struct fec_info_s *info)
+{
+	volatile fec_t *fecp = (fec_t *) (info->miibase);
+	int i;
+
+	fecp->ecr = FEC_ECR_RESET;
+	for (i = 0; (fecp->ecr & FEC_ECR_RESET) && (i < FEC_RESET_DELAY); ++i) {
+		udelay(1);
+	}
+	if (i == FEC_RESET_DELAY) {
+		printf("FEC_RESET_DELAY timeout\n");
+	}
+}
+
+/* send command to phy using mii, wait for result */
+uint mii_send(uint mii_cmd)
+{
+	struct fec_info_s *info;
+	struct eth_device *dev;
+	volatile fec_t *ep;
+	uint mii_reply;
+	int j = 0;
+
+	/* retrieve from register structure */
+	dev = eth_get_dev();
+	info = dev->priv;
+
+	ep = (fec_t *) info->miibase;
+
+	ep->mmfr = mii_cmd;	/* command to phy */
+
+	/* wait for mii complete */
+	while (!(ep->eir & FEC_EIR_MII) && (j < MCFFEC_TOUT_LOOP)) {
+		udelay(1);
+		j++;
+	}
+	if (j >= MCFFEC_TOUT_LOOP) {
+		printf("MII not complete\n");
+		return -1;
+	}
+
+	mii_reply = ep->mmfr;	/* result from phy */
+	ep->eir = FEC_EIR_MII;	/* clear MII complete */
+#ifdef ET_DEBUG
+	printf("%s[%d] %s: sent=0x%8.8x, reply=0x%8.8x\n",
+	       __FILE__, __LINE__, __FUNCTION__, mii_cmd, mii_reply);
+#endif
+
+	return (mii_reply & 0xffff);	/* data read from phy */
+}
+#endif				/* CFG_DISCOVER_PHY || CONFIG_CMD_MII */
+
+#if defined(CFG_DISCOVER_PHY)
+int mii_discover_phy(struct eth_device *dev)
+{
+#define MAX_PHY_PASSES 11
+	struct fec_info_s *info = dev->priv;
+	int phyaddr, pass;
+	uint phyno, phytype;
+
+	if (info->phyname_init)
+		return info->phy_addr;
+
+	phyaddr = -1;		/* didn't find a PHY yet */
+	for (pass = 1; pass <= MAX_PHY_PASSES && phyaddr < 0; ++pass) {
+		if (pass > 1) {
+			/* PHY may need more time to recover from reset.
+			 * The LXT970 needs 50ms typical, no maximum is
+			 * specified, so wait 10ms before try again.
+			 * With 11 passes this gives it 100ms to wake up.
+			 */
+			udelay(10000);	/* wait 10ms */
+		}
+
+		for (phyno = 0; phyno < 32 && phyaddr < 0; ++phyno) {
+
+			phytype = mii_send(mk_mii_read(phyno, PHY_PHYIDR1));
+#ifdef ET_DEBUG
+			printf("PHY type 0x%x pass %d type\n", phytype, pass);
+#endif
+			if (phytype != 0xffff) {
+				phyaddr = phyno;
+				phytype <<= 16;
+				phytype |=
+				    mii_send(mk_mii_read(phyno, PHY_PHYIDR2));
+
+				switch (phytype & 0xffffffff) {
+				case PHY_ID_KS8721BL:
+					strcpy(info->phy_name,
+					       STR_ID_KS8721BL);
+					info->phyname_init = 1;
+					break;
+				default:
+					strcpy(info->phy_name, "unknown");
+					info->phyname_init = 1;
+					break;
+				}
+
+#ifdef ET_DEBUG
+				printf("PHY @ 0x%x pass %d type ", phyno, pass);
+				switch (phytype & 0xffffffff) {
+				case PHY_ID_KS8721BL:
+					printf(STR_ID_KS8721BL);
+					break;
+				default:
+					printf("0x%08x\n", phytype);
+					break;
+				}
+#endif
+			}
+		}
+	}
+	if (phyaddr < 0)
+		printf("No PHY device found.\n");
+
+	return phyaddr;
+}
+#endif				/* CFG_DISCOVER_PHY */
+
+void mii_init(void) __attribute__((weak,alias("__mii_init")));
+
+void __mii_init(void)
+{
+	volatile fec_t *fecp;
+	struct fec_info_s *info;
+	struct eth_device *dev;
+	int miispd = 0, i = 0;
+	u16 autoneg = 0;
+
+	/* retrieve from register structure */
+	dev = eth_get_dev();
+	info = dev->priv;
+
+	fecp = (fec_t *) info->miibase;
+
+	fecpin_setclear(dev, 1);
+
+	mii_reset(info);
+
+	/* We use strictly polling mode only */
+	fecp->eimr = 0;
+
+	/* Clear any pending interrupt */
+	fecp->eir = 0xffffffff;
+
+	/* Set MII speed */
+	miispd = (gd->bus_clk / 1000000) / 5;
+	fecp->mscr = miispd << 1;
+
+	info->phy_addr = mii_discover_phy(dev);
+
+#define AUTONEGLINK		(PHY_BMSR_AUTN_COMP | PHY_BMSR_LS)
+	while (i < MCFFEC_TOUT_LOOP) {
+		autoneg = 0;
+		miiphy_read(dev->name, info->phy_addr, PHY_BMSR, &autoneg);
+		i++;
+
+		if ((autoneg & AUTONEGLINK) == AUTONEGLINK)
+			break;
+
+		udelay(500);
+	}
+	if (i >= MCFFEC_TOUT_LOOP) {
+		printf("Auto Negotiation not complete\n");
+	}
+
+	/* adapt to the half/full speed settings */
+	info->dup_spd = miiphy_duplex(dev->name, info->phy_addr) << 16;
+	info->dup_spd |= miiphy_speed(dev->name, info->phy_addr);
+}
+
+/*****************************************************************************
+ * Read and write a MII PHY register, routines used by MII Utilities
+ *
+ * FIXME: These routines are expected to return 0 on success, but mii_send
+ *	  does _not_ return an error code. Maybe 0xFFFF means error, i.e.
+ *	  no PHY connected...
+ *	  For now always return 0.
+ * FIXME: These routines only work after calling eth_init() at least once!
+ *	  Otherwise they hang in mii_send() !!! Sorry!
+ *****************************************************************************/
+
+int mcffec_miiphy_read(char *devname, unsigned char addr, unsigned char reg,
+		       unsigned short *value)
+{
+	short rdreg;		/* register working value */
+
+#ifdef MII_DEBUG
+	printf("miiphy_read(0x%x) @ 0x%x = ", reg, addr);
+#endif
+	rdreg = mii_send(mk_mii_read(addr, reg));
+
+	*value = rdreg;
+
+#ifdef MII_DEBUG
+	printf("0x%04x\n", *value);
+#endif
+
+	return 0;
+}
+
+int mcffec_miiphy_write(char *devname, unsigned char addr, unsigned char reg,
+			unsigned short value)
+{
+	short rdreg;		/* register working value */
+
+#ifdef MII_DEBUG
+	printf("miiphy_write(0x%x) @ 0x%x = ", reg, addr);
+#endif
+
+	rdreg = mii_send(mk_mii_write(addr, reg, value));
+
+#ifdef MII_DEBUG
+	printf("0x%04x\n", value);
+#endif
+
+	return 0;
+}
+
+#endif				/* CONFIG_CMD_NET, FEC_ENET & NET_MULTI */
diff --git a/board/freescale/m5271evb/u-boot.lds b/board/freescale/m5271evb/u-boot.lds
new file mode 100644
index 0000000000..c07d023834
--- /dev/null
+++ b/board/freescale/m5271evb/u-boot.lds
@@ -0,0 +1,144 @@
+/*
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+OUTPUT_ARCH(m68k)
+/* Do we need any of these for elf?
+   __DYNAMIC = 0;    */
+GROUP(libgcc.a)
+SECTIONS
+{
+  /* Read-only sections, merged into text segment: */
+  . = + SIZEOF_HEADERS;
+  .interp : { *(.interp) }
+  .hash          : { *(.hash)		}
+  .dynsym        : { *(.dynsym)		}
+  .dynstr        : { *(.dynstr)		}
+  .rel.text      : { *(.rel.text)		}
+  .rela.text     : { *(.rela.text)	}
+  .rel.data      : { *(.rel.data)		}
+  .rela.data     : { *(.rela.data)	}
+  .rel.rodata    : { *(.rel.rodata)	}
+  .rela.rodata   : { *(.rela.rodata)	}
+  .rel.got       : { *(.rel.got)		}
+  .rela.got      : { *(.rela.got)		}
+  .rel.ctors     : { *(.rel.ctors)	}
+  .rela.ctors    : { *(.rela.ctors)	}
+  .rel.dtors     : { *(.rel.dtors)	}
+  .rela.dtors    : { *(.rela.dtors)	}
+  .rel.bss       : { *(.rel.bss)		}
+  .rela.bss      : { *(.rela.bss)		}
+  .rel.plt       : { *(.rel.plt)		}
+  .rela.plt      : { *(.rela.plt)		}
+  .init          : { *(.init)	}
+  .plt : { *(.plt) }
+  .text      :
+  {
+    /* WARNING - the following is hand-optimized to fit within	*/
+    /* the sector layout of our flash chips!	XXX FIXME XXX	*/
+
+    cpu/mcf52x2/start.o		(.text)
+    lib_m68k/traps.o		(.text)
+    cpu/mcf52x2/interrupts.o	(.text)
+    common/dlmalloc.o		(.text)
+    lib_generic/zlib.o		(.text)
+
+    . = DEFINED(env_offset) ? env_offset : .;
+    common/environment.o	(.ppcenv)
+
+    *(.text)
+    *(.fixup)
+    *(.got1)
+  }
+  _etext = .;
+  PROVIDE (etext = .);
+  .rodata    :
+  {
+    *(.rodata)
+    *(.rodata1)
+  }
+  .fini      : { *(.fini)    } =0
+  .ctors     : { *(.ctors)   }
+  .dtors     : { *(.dtors)   }
+
+  /* Read-write section, merged into data segment: */
+  . = (. + 0x00FF) & 0xFFFFFF00;
+  _erotext = .;
+  PROVIDE (erotext = .);
+
+  .reloc   :
+  {
+    __got_start = .;
+    *(.got)
+    __got_end = .;
+    _GOT2_TABLE_ = .;
+    *(.got2)
+    _FIXUP_TABLE_ = .;
+    *(.fixup)
+  }
+  __got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >>2;
+  __fixup_entries = (. - _FIXUP_TABLE_)>>2;
+
+  .data    :
+  {
+    *(.data)
+    *(.data1)
+    *(.sdata)
+    *(.sdata2)
+    *(.dynamic)
+    CONSTRUCTORS
+  }
+  _edata  =  .;
+  PROVIDE (edata = .);
+
+  . = .;
+  __u_boot_cmd_start = .;
+  .u_boot_cmd : { *(.u_boot_cmd) }
+  __u_boot_cmd_end = .;
+
+
+  . = .;
+  __start___ex_table = .;
+  __ex_table : { *(__ex_table) }
+  __stop___ex_table = .;
+
+  . = ALIGN(256);
+  __init_begin = .;
+  .text.init : { *(.text.init) }
+  .data.init : { *(.data.init) }
+  . = ALIGN(256);
+  __init_end = .;
+
+  __bss_start = .;
+  .bss (NOLOAD)       :
+  {
+   _sbss = .;
+   *(.sbss) *(.scommon)
+   *(.dynbss)
+   *(.bss)
+   *(COMMON)
+   . = ALIGN(4);
+   _ebss = .;
+  }
+  _end = . ;
+  PROVIDE (end = .);
+}