arch/arm/cpu/tegra20-common/warmboot.c - platform/external/u-boot - Gitiles

 /*
  * (C) Copyright 2010 - 2011
  * NVIDIA Corporation <www.nvidia.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/io.h>
 #include <asm/errno.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/emc.h>
 #include <asm/arch/gp_padctrl.h>
 #include <asm/arch/pinmux.h>
 #include <asm/arch/sdram_param.h>
 #include <asm/arch/tegra.h>
 #include <asm/arch-tegra/ap.h>
 #include <asm/arch-tegra/clk_rst.h>
 #include <asm/arch-tegra/pmc.h>
 #include <asm/arch-tegra/fuse.h>
 #include <asm/arch-tegra/warmboot.h>

 DECLARE_GLOBAL_DATA_PTR;

 #ifndef CONFIG_TEGRA_CLOCK_SCALING
 #error "You must enable CONFIG_TEGRA_CLOCK_SCALING to use CONFIG_TEGRA_LP0"
 #endif

 /*
  * This is the place in SRAM where the SDRAM parameters are stored. There
  * are 4 blocks, one for each RAM code
  */
 #define SDRAM_PARAMS_BASE	(AP20_BASE_PA_SRAM + 0x188)

 /* TODO: If we later add support for the Misc GP controller, refactor this */
 union xm2cfga_reg {
 	struct {
 		u32 reserved0:2;
 		u32 hsm_en:1;
 		u32 reserved1:2;
 		u32 preemp_en:1;
 		u32 vref_en:1;
 		u32 reserved2:5;
 		u32 cal_drvdn:5;
 		u32 reserved3:3;
 		u32 cal_drvup:5;
 		u32 reserved4:3;
 		u32 cal_drvdn_slwr:2;
 		u32 cal_drvup_slwf:2;
 	};
 	u32 word;
 };

 union xm2cfgd_reg {
 	struct {
 		u32 reserved0:2;
 		u32 hsm_en:1;
 		u32 schmt_en:1;
 		u32 lpmd:2;
 		u32 vref_en:1;
 		u32 reserved1:5;
 		u32 cal_drvdn:5;
 		u32 reserved2:3;
 		u32 cal_drvup:5;
 		u32 reserved3:3;
 		u32 cal_drvdn_slwr:2;
 		u32 cal_drvup_slwf:2;
 	};
 	u32 word;
 };

 /*
  * TODO: This register is not documented in the TRM yet. We could move this
  * into the EMC and give it a proper interface, but not while it is
  * undocumented.
  */
 union fbio_spare_reg {
 	struct {
 		u32 reserved:24;
 		u32 cfg_wb0:8;
 	};
 	u32 word;
 };

 /* We pack the resume information into these unions for later */
 union scratch2_reg {
 	struct {
 		u32 pllm_base_divm:5;
 		u32 pllm_base_divn:10;
 		u32 pllm_base_divp:3;
 		u32 pllm_misc_lfcon:4;
 		u32 pllm_misc_cpcon:4;
 		u32 gp_xm2cfga_padctrl_preemp:1;
 		u32 gp_xm2cfgd_padctrl_schmt:1;
 		u32 osc_ctrl_xobp:1;
 		u32 memory_type:3;
 	};
 	u32 word;
 };

 union scratch4_reg {
 	struct {
 		u32 emc_clock_divider:8;
 		u32 pllm_stable_time:8;
 		u32 pllx_stable_time:8;
 		u32 emc_fbio_spare_cfg_wb0:8;
 	};
 	u32 word;
 };

 union scratch24_reg {
 	struct {
 		u32 emc_auto_cal_wait:8;
 		u32 emc_pin_program_wait:8;
 		u32 warmboot_wait:8;
 		u32 reserved:8;
 	};
 	u32 word;
 };

 int warmboot_save_sdram_params(void)
 {
 	u32 ram_code;
 	struct sdram_params sdram;
 	struct pmux_tri_ctlr *pmt = (struct pmux_tri_ctlr *)NV_PA_APB_MISC_BASE;
 	struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
 	struct apb_misc_gp_ctlr *gp =
 			(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;
 	struct emc_ctlr *emc = emc_get_controller(gd->fdt_blob);
 	union scratch2_reg scratch2;
 	union scratch4_reg scratch4;
 	union scratch24_reg scratch24;
 	union xm2cfga_reg xm2cfga;
 	union xm2cfgd_reg xm2cfgd;
 	union fbio_spare_reg fbio_spare;

 	/* get ram code that is used as index to array sdram_params in BCT */
 	ram_code = (readl(&pmt->pmt_strap_opt_a) >>
 			STRAP_OPT_A_RAM_CODE_SHIFT) & 3;
 	memcpy(&sdram,
 	       (char *)((struct sdram_params *)SDRAM_PARAMS_BASE + ram_code),
 	       sizeof(sdram));

 	xm2cfga.word = readl(&gp->xm2cfga);
 	xm2cfgd.word = readl(&gp->xm2cfgd);

 	scratch2.word = 0;
 	scratch2.osc_ctrl_xobp = clock_get_osc_bypass();

 	/* Get the memory PLL settings */
 	{
 		u32 divm, divn, divp, cpcon, lfcon;

 		if (clock_ll_read_pll(CLOCK_ID_MEMORY, &divm, &divn, &divp,
 					&cpcon, &lfcon))
 			return -1;
 		scratch2.pllm_base_divm = divm;
 		scratch2.pllm_base_divn = divn;
 		scratch2.pllm_base_divp = divp;
 		scratch2.pllm_misc_cpcon = cpcon;
 		scratch2.pllm_misc_lfcon = lfcon;
 	}

 	scratch2.gp_xm2cfga_padctrl_preemp = xm2cfga.preemp_en;
 	scratch2.gp_xm2cfgd_padctrl_schmt = xm2cfgd.schmt_en;
 	scratch2.memory_type = sdram.memory_type;
 	writel(scratch2.word, &pmc->pmc_scratch2);

 	/* collect data from various sources for pmc_scratch4 */
 	fbio_spare.word = readl(&emc->fbio_spare);
 	scratch4.word = 0;
 	scratch4.emc_fbio_spare_cfg_wb0 = fbio_spare.cfg_wb0;
 	scratch4.emc_clock_divider = sdram.emc_clock_divider;
 	scratch4.pllm_stable_time = -1;
 	scratch4.pllx_stable_time = -1;
 	writel(scratch4.word, &pmc->pmc_scratch4);

 	/* collect various data from sdram for pmc_scratch24 */
 	scratch24.word = 0;
 	scratch24.emc_pin_program_wait = sdram.emc_pin_program_wait;
 	scratch24.emc_auto_cal_wait = sdram.emc_auto_cal_wait;
 	scratch24.warmboot_wait = sdram.warm_boot_wait;
 	writel(scratch24.word, &pmc->pmc_scratch24);

 	return 0;
 }

 static u32 get_major_version(void)
 {
 	u32 major_id;
 	struct apb_misc_gp_ctlr *gp =
 		(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;

 	major_id = (readl(&gp->hidrev) & HIDREV_MAJORPREV_MASK) >>
 			HIDREV_MAJORPREV_SHIFT;
 	return major_id;
 }

 static int is_production_mode_fuse_set(struct fuse_regs *fuse)
 {
 	return readl(&fuse->production_mode);
 }

 static int is_odm_production_mode_fuse_set(struct fuse_regs *fuse)
 {
 	return readl(&fuse->security_mode);
 }

 static int is_failure_analysis_mode(struct fuse_regs *fuse)
 {
 	return readl(&fuse->fa);
 }

 static int ap20_is_odm_production_mode(void)
 {
 	struct fuse_regs *fuse = (struct fuse_regs *)NV_PA_FUSE_BASE;

 	if (!is_failure_analysis_mode(fuse) &&
 	    is_odm_production_mode_fuse_set(fuse))
 		return 1;
 	else
 		return 0;
 }

 static int ap20_is_production_mode(void)
 {
 	struct fuse_regs *fuse = (struct fuse_regs *)NV_PA_FUSE_BASE;

 	if (get_major_version() == 0)
 		return 1;

 	if (!is_failure_analysis_mode(fuse) &&
 	    is_production_mode_fuse_set(fuse) &&
 	    !is_odm_production_mode_fuse_set(fuse))
 		return 1;
 	else
 		return 0;
 }

 static enum fuse_operating_mode fuse_get_operation_mode(void)
 {
 	u32 chip_id;
 	struct apb_misc_gp_ctlr *gp =
 		(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;

 	chip_id = (readl(&gp->hidrev) & HIDREV_CHIPID_MASK) >>
 			HIDREV_CHIPID_SHIFT;
 	if (chip_id == CHIPID_TEGRA20) {
 		if (ap20_is_odm_production_mode()) {
 			printf("!! odm_production_mode is not supported !!\n");
 			return MODE_UNDEFINED;
 		} else
 			if (ap20_is_production_mode())
 				return MODE_PRODUCTION;
 			else
 				return MODE_UNDEFINED;
 	}
 	return MODE_UNDEFINED;
 }

 static void determine_crypto_options(int *is_encrypted, int *is_signed,
 				     int *use_zero_key)
 {
 	switch (fuse_get_operation_mode()) {
 	case MODE_PRODUCTION:
 		*is_encrypted = 0;
 		*is_signed = 1;
 		*use_zero_key = 1;
 		break;
 	case MODE_UNDEFINED:
 	default:
 		*is_encrypted = 0;
 		*is_signed = 0;
 		*use_zero_key  = 0;
 		break;
 	}
 }

 static int sign_wb_code(u32 start, u32 length, int use_zero_key)
 {
 	int err;
 	u8 *source;		/* Pointer to source */
 	u8 *hash;

 	/* Calculate AES block parameters. */
 	source = (u8 *)(start + offsetof(struct wb_header, random_aes_block));
 	length -= offsetof(struct wb_header, random_aes_block);
 	hash = (u8 *)(start + offsetof(struct wb_header, hash));
 	err = sign_data_block(source, length, hash);

 	return err;
 }

 int warmboot_prepare_code(u32 seg_address, u32 seg_length)
 {
 	int err = 0;
 	u32 length;			/* length of the signed/encrypt code */
 	struct wb_header *dst_header;	/* Pointer to dest WB header */
 	int is_encrypted;		/* Segment is encrypted */
 	int is_signed;			/* Segment is signed */
 	int use_zero_key;		/* Use key of all zeros */

 	/* Determine crypto options. */
 	determine_crypto_options(&is_encrypted, &is_signed, &use_zero_key);

 	/* Get the actual code limits. */
 	length = roundup(((u32)wb_end - (u32)wb_start), 16);

 	/*
 	 * The region specified by seg_address must be in SDRAM and must be
 	 * nonzero in length.
 	 */
 	if (seg_length == 0 || seg_address < NV_PA_SDRAM_BASE ||
 		seg_address + seg_length >= NV_PA_SDRAM_BASE + gd->ram_size) {
 		err = -EFAULT;
 		goto fail;
 	}

 	/* Things must be 16-byte aligned. */
 	if ((seg_length & 0xF) || (seg_address & 0xF)) {
 		err = -EINVAL;
 		goto fail;
 	}

 	/* Will the code fit? (destination includes wb_header + wb code) */
 	if (seg_length < (length + sizeof(struct wb_header))) {
 		err = -EINVAL;
 		goto fail;
 	}

 	dst_header = (struct wb_header *)seg_address;
 	memset((char *)dst_header, 0, sizeof(struct wb_header));

 	/* Populate the random_aes_block as requested. */
 	{
 		u32 *aes_block = (u32 *)&(dst_header->random_aes_block);
 		u32 *end = (u32 *)(((u32)aes_block) +
 				   sizeof(dst_header->random_aes_block));

 		do {
 			*aes_block++ = 0;
 		} while (aes_block < end);
 	}

 	/* Populate the header. */
 	dst_header->length_insecure = length + sizeof(struct wb_header);
 	dst_header->length_secure = length + sizeof(struct wb_header);
 	dst_header->destination = NV_WB_RUN_ADDRESS;
 	dst_header->entry_point = NV_WB_RUN_ADDRESS;
 	dst_header->code_length = length;

 	if (is_encrypted) {
 		printf("!!!! Encryption is not supported !!!!\n");
 		dst_header->length_insecure = 0;
 		err = -EACCES;
 		goto fail;
 	} else
 		/* copy the wb code directly following dst_header. */
 		memcpy((char *)(dst_header+1), (char *)wb_start, length);

 	if (is_signed)
 		err = sign_wb_code(seg_address, dst_header->length_insecure,
 				   use_zero_key);

 fail:
 	if (err)
 		printf("Warning: warmboot code copy failed (error=%d)\n", err);

 	return err;
 }
	/*
	* (C) Copyright 2010 - 2011
	* NVIDIA Corporation <www.nvidia.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/io.h>
	#include <asm/errno.h>
	#include <asm/arch/clock.h>
	#include <asm/arch/emc.h>
	#include <asm/arch/gp_padctrl.h>
	#include <asm/arch/pinmux.h>
	#include <asm/arch/sdram_param.h>
	#include <asm/arch/tegra.h>
	#include <asm/arch-tegra/ap.h>
	#include <asm/arch-tegra/clk_rst.h>
	#include <asm/arch-tegra/pmc.h>
	#include <asm/arch-tegra/fuse.h>
	#include <asm/arch-tegra/warmboot.h>

	DECLARE_GLOBAL_DATA_PTR;

	#ifndef CONFIG_TEGRA_CLOCK_SCALING
	#error "You must enable CONFIG_TEGRA_CLOCK_SCALING to use CONFIG_TEGRA_LP0"
	#endif

	/*
	* This is the place in SRAM where the SDRAM parameters are stored. There
	* are 4 blocks, one for each RAM code
	*/
	#define SDRAM_PARAMS_BASE (AP20_BASE_PA_SRAM + 0x188)

	/* TODO: If we later add support for the Misc GP controller, refactor this */
	union xm2cfga_reg {
	struct {
	u32 reserved0:2;
	u32 hsm_en:1;
	u32 reserved1:2;
	u32 preemp_en:1;
	u32 vref_en:1;
	u32 reserved2:5;
	u32 cal_drvdn:5;
	u32 reserved3:3;
	u32 cal_drvup:5;
	u32 reserved4:3;
	u32 cal_drvdn_slwr:2;
	u32 cal_drvup_slwf:2;
	};
	u32 word;
	};

	union xm2cfgd_reg {
	struct {
	u32 reserved0:2;
	u32 hsm_en:1;
	u32 schmt_en:1;
	u32 lpmd:2;
	u32 vref_en:1;
	u32 reserved1:5;
	u32 cal_drvdn:5;
	u32 reserved2:3;
	u32 cal_drvup:5;
	u32 reserved3:3;
	u32 cal_drvdn_slwr:2;
	u32 cal_drvup_slwf:2;
	};
	u32 word;
	};

	/*
	* TODO: This register is not documented in the TRM yet. We could move this
	* into the EMC and give it a proper interface, but not while it is
	* undocumented.
	*/
	union fbio_spare_reg {
	struct {
	u32 reserved:24;
	u32 cfg_wb0:8;
	};
	u32 word;
	};

	/* We pack the resume information into these unions for later */
	union scratch2_reg {
	struct {
	u32 pllm_base_divm:5;
	u32 pllm_base_divn:10;
	u32 pllm_base_divp:3;
	u32 pllm_misc_lfcon:4;
	u32 pllm_misc_cpcon:4;
	u32 gp_xm2cfga_padctrl_preemp:1;
	u32 gp_xm2cfgd_padctrl_schmt:1;
	u32 osc_ctrl_xobp:1;
	u32 memory_type:3;
	};
	u32 word;
	};

	union scratch4_reg {
	struct {
	u32 emc_clock_divider:8;
	u32 pllm_stable_time:8;
	u32 pllx_stable_time:8;
	u32 emc_fbio_spare_cfg_wb0:8;
	};
	u32 word;
	};

	union scratch24_reg {
	struct {
	u32 emc_auto_cal_wait:8;
	u32 emc_pin_program_wait:8;
	u32 warmboot_wait:8;
	u32 reserved:8;
	};
	u32 word;
	};

	int warmboot_save_sdram_params(void)
	{
	u32 ram_code;
	struct sdram_params sdram;
	struct pmux_tri_ctlr pmt = (struct pmux_tri_ctlr )NV_PA_APB_MISC_BASE;
	struct pmc_ctlr pmc = (struct pmc_ctlr )NV_PA_PMC_BASE;
	struct apb_misc_gp_ctlr *gp =
	(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;
	struct emc_ctlr *emc = emc_get_controller(gd->fdt_blob);
	union scratch2_reg scratch2;
	union scratch4_reg scratch4;
	union scratch24_reg scratch24;
	union xm2cfga_reg xm2cfga;
	union xm2cfgd_reg xm2cfgd;
	union fbio_spare_reg fbio_spare;

	/* get ram code that is used as index to array sdram_params in BCT */
	ram_code = (readl(&pmt->pmt_strap_opt_a) >>
	STRAP_OPT_A_RAM_CODE_SHIFT) & 3;
	memcpy(&sdram,
	(char )((struct sdram_params )SDRAM_PARAMS_BASE + ram_code),
	sizeof(sdram));

	xm2cfga.word = readl(&gp->xm2cfga);
	xm2cfgd.word = readl(&gp->xm2cfgd);

	scratch2.word = 0;
	scratch2.osc_ctrl_xobp = clock_get_osc_bypass();

	/* Get the memory PLL settings */
	{
	u32 divm, divn, divp, cpcon, lfcon;

	if (clock_ll_read_pll(CLOCK_ID_MEMORY, &divm, &divn, &divp,
	&cpcon, &lfcon))
	return -1;
	scratch2.pllm_base_divm = divm;
	scratch2.pllm_base_divn = divn;
	scratch2.pllm_base_divp = divp;
	scratch2.pllm_misc_cpcon = cpcon;
	scratch2.pllm_misc_lfcon = lfcon;
	}

	scratch2.gp_xm2cfga_padctrl_preemp = xm2cfga.preemp_en;
	scratch2.gp_xm2cfgd_padctrl_schmt = xm2cfgd.schmt_en;
	scratch2.memory_type = sdram.memory_type;
	writel(scratch2.word, &pmc->pmc_scratch2);

	/* collect data from various sources for pmc_scratch4 */
	fbio_spare.word = readl(&emc->fbio_spare);
	scratch4.word = 0;
	scratch4.emc_fbio_spare_cfg_wb0 = fbio_spare.cfg_wb0;
	scratch4.emc_clock_divider = sdram.emc_clock_divider;
	scratch4.pllm_stable_time = -1;
	scratch4.pllx_stable_time = -1;
	writel(scratch4.word, &pmc->pmc_scratch4);

	/* collect various data from sdram for pmc_scratch24 */
	scratch24.word = 0;
	scratch24.emc_pin_program_wait = sdram.emc_pin_program_wait;
	scratch24.emc_auto_cal_wait = sdram.emc_auto_cal_wait;
	scratch24.warmboot_wait = sdram.warm_boot_wait;
	writel(scratch24.word, &pmc->pmc_scratch24);

	return 0;
	}

	static u32 get_major_version(void)
	{
	u32 major_id;
	struct apb_misc_gp_ctlr *gp =
	(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;

	major_id = (readl(&gp->hidrev) & HIDREV_MAJORPREV_MASK) >>
	HIDREV_MAJORPREV_SHIFT;
	return major_id;
	}

	static int is_production_mode_fuse_set(struct fuse_regs *fuse)
	{
	return readl(&fuse->production_mode);
	}

	static int is_odm_production_mode_fuse_set(struct fuse_regs *fuse)
	{
	return readl(&fuse->security_mode);
	}

	static int is_failure_analysis_mode(struct fuse_regs *fuse)
	{
	return readl(&fuse->fa);
	}

	static int ap20_is_odm_production_mode(void)
	{
	struct fuse_regs fuse = (struct fuse_regs )NV_PA_FUSE_BASE;

	if (!is_failure_analysis_mode(fuse) &&
	is_odm_production_mode_fuse_set(fuse))
	return 1;
	else
	return 0;
	}

	static int ap20_is_production_mode(void)
	{
	struct fuse_regs fuse = (struct fuse_regs )NV_PA_FUSE_BASE;

	if (get_major_version() == 0)
	return 1;

	if (!is_failure_analysis_mode(fuse) &&
	is_production_mode_fuse_set(fuse) &&
	!is_odm_production_mode_fuse_set(fuse))
	return 1;
	else
	return 0;
	}

	static enum fuse_operating_mode fuse_get_operation_mode(void)
	{
	u32 chip_id;
	struct apb_misc_gp_ctlr *gp =
	(struct apb_misc_gp_ctlr *)NV_PA_APB_MISC_GP_BASE;

	chip_id = (readl(&gp->hidrev) & HIDREV_CHIPID_MASK) >>
	HIDREV_CHIPID_SHIFT;
	if (chip_id == CHIPID_TEGRA20) {
	if (ap20_is_odm_production_mode()) {
	printf("!! odm_production_mode is not supported !!\n");
	return MODE_UNDEFINED;
	} else
	if (ap20_is_production_mode())
	return MODE_PRODUCTION;
	else
	return MODE_UNDEFINED;
	}
	return MODE_UNDEFINED;
	}

	static void determine_crypto_options(int is_encrypted, int is_signed,
	int *use_zero_key)
	{
	switch (fuse_get_operation_mode()) {
	case MODE_PRODUCTION:
	*is_encrypted = 0;
	*is_signed = 1;
	*use_zero_key = 1;
	break;
	case MODE_UNDEFINED:
	default:
	*is_encrypted = 0;
	*is_signed = 0;
	*use_zero_key = 0;
	break;
	}
	}

	static int sign_wb_code(u32 start, u32 length, int use_zero_key)
	{
	int err;
	u8 source; / Pointer to source */
	u8 *hash;

	/* Calculate AES block parameters. */
	source = (u8 *)(start + offsetof(struct wb_header, random_aes_block));
	length -= offsetof(struct wb_header, random_aes_block);
	hash = (u8 *)(start + offsetof(struct wb_header, hash));
	err = sign_data_block(source, length, hash);

	return err;
	}

	int warmboot_prepare_code(u32 seg_address, u32 seg_length)
	{
	int err = 0;
	u32 length; /* length of the signed/encrypt code */
	struct wb_header dst_header; / Pointer to dest WB header */
	int is_encrypted; /* Segment is encrypted */
	int is_signed; /* Segment is signed */
	int use_zero_key; /* Use key of all zeros */

	/* Determine crypto options. */
	determine_crypto_options(&is_encrypted, &is_signed, &use_zero_key);

	/* Get the actual code limits. */
	length = roundup(((u32)wb_end - (u32)wb_start), 16);

	/*
	* The region specified by seg_address must be in SDRAM and must be
	* nonzero in length.
	*/
	if (seg_length == 0 \|\| seg_address < NV_PA_SDRAM_BASE \|\|
	seg_address + seg_length >= NV_PA_SDRAM_BASE + gd->ram_size) {
	err = -EFAULT;
	goto fail;
	}

	/* Things must be 16-byte aligned. */
	if ((seg_length & 0xF) \|\| (seg_address & 0xF)) {
	err = -EINVAL;
	goto fail;
	}

	/* Will the code fit? (destination includes wb_header + wb code) */
	if (seg_length < (length + sizeof(struct wb_header))) {
	err = -EINVAL;
	goto fail;
	}

	dst_header = (struct wb_header *)seg_address;
	memset((char *)dst_header, 0, sizeof(struct wb_header));

	/* Populate the random_aes_block as requested. */
	{
	u32 aes_block = (u32 )&(dst_header->random_aes_block);
	u32 end = (u32 )(((u32)aes_block) +
	sizeof(dst_header->random_aes_block));

	do {
	*aes_block++ = 0;
	} while (aes_block < end);
	}

	/* Populate the header. */
	dst_header->length_insecure = length + sizeof(struct wb_header);
	dst_header->length_secure = length + sizeof(struct wb_header);
	dst_header->destination = NV_WB_RUN_ADDRESS;
	dst_header->entry_point = NV_WB_RUN_ADDRESS;
	dst_header->code_length = length;

	if (is_encrypted) {
	printf("!!!! Encryption is not supported !!!!\n");
	dst_header->length_insecure = 0;
	err = -EACCES;
	goto fail;
	} else
	/* copy the wb code directly following dst_header. */
	memcpy((char )(dst_header+1), (char )wb_start, length);

	if (is_signed)
	err = sign_wb_code(seg_address, dst_header->length_insecure,
	use_zero_key);

	fail:
	if (err)
	printf("Warning: warmboot code copy failed (error=%d)\n", err);

	return err;
	}