IMX8MQ replace 4G lpddr4 issue

coindu — Thu, 12 Nov 2020 02:49:35 GMT

I want to replace 4G LPDDR4 but it cannot start on uboot stage with L4.19.35 bsp.

1) first use ddr tools to generate lpddr4_timing.c and replace uboot-imx\board\freescale\imx8mq_evk\lpddr4_timing.c

modify uboot-imx\include\configs\imx8mq_evk.h #define PHYS_SDRAM_SIZE 0xC0000000 /* 3GB DDR */ to 0x100000000 /* 4GB DDR */

finally it will stuck with

U-Boot 2019.04-4.19.35-1.1.0+g718e897 (Nov 12 2020 - 02:23:21 +0000)

CPU: Freescale i.MX8MQ rev2.1 1300 MHz (running at 800 MHz)
CPU: Industrial temperature grade (-40C to 105C) at 45C
Reset cause: POR
Model: Freescale i.MX8MQ EVK
DRAM:

2) IMX8MM has a configuration option CONFIG_IMX8M_4G_LPDDR4=y . and it will use other file

uboot-imx\board\freescale\imx8mm_evk\Makefile

ifdef CONFIG_SPL_BUILD
obj-y += spl.o
ifdef CONFIG_IMX8M_4G_LPDDR4
obj-y += lpddr4_timing_4g.o
else
obj-$(CONFIG_IMX8M_LPDDR4) += lpddr4_timing.o
obj-$(CONFIG_IMX8M_DDR4) += ddr4_timing.o
endif
endif

I do not know how to generate lpddr4_timing_4g.c !

and it seem split 4G DDR to 3G and 1G in uboot-imx\include\configs\imx8mm_evk_android.h

#ifdef CONFIG_IMX8M_4G_LPDDR4
#undef PHYS_SDRAM_SIZE
#define PHYS_SDRAM_SIZE 0xC0000000 /* 3GB */
#define PHYS_SDRAM_2 0x100000000
#define PHYS_SDRAM_2_SIZE 0x40000000 /* 1GB */
#undef CONFIG_NR_DRAM_BANKS
#define CONFIG_NR_DRAM_BANKS 2
#endif

finally i add this modify to uboot-imx\include\configs\imx8mq_evk.h and add modiy uboot-imx\board\freescale\imx8mq_evk/imx8mq_evk.c

int dram_init_banksize(void)
{
printf("dram init banksize\n");
gd->bd->bi_dram[0].start = PHYS_SDRAM;
if (rom_pointer[1])
gd->bd->bi_dram[0].size = PHYS_SDRAM_SIZE -rom_pointer[1];
else
gd->bd->bi_dram[0].size = PHYS_SDRAM_SIZE;

#if CONFIG_NR_DRAM_BANKS == 2
gd->bd->bi_dram[1].start = PHYS_SDRAM_2;
gd->bd->bi_dram[1].size = PHYS_SDRAM_2_SIZE;
#endif

return 0;
}

then the uboot can boot up ,but stuck in kernel .

[ 0.000000] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
[ 0.000000] Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
[ 0.000000] Modules linked in:
[ 0.000000] Process swapper (pid: 0, stack limit = 0x(____ptrval____))
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.35-1.1.0+gcecf053 #1
[ 0.000000] Hardware name: Freescale i.MX8MQ EVK PMIC BD71837 (DT)
[ 0.000000] pstate: 40000085 (nZcv daIf -PAN -UAO)
[ 0.000000] pc : __create_pgd_mapping+0x74/0x5c8
[ 0.000000] lr : map_kernel_segment+0x70/0xa4
[ 0.000000] sp : ffff0000096c3d60
[ 0.000000] x29: ffff0000096c3d60 x28: ffff000008080000
[ 0.000000] x27: ffff7dfffe636000 x26: ffff008000000000
[ 0.000000] x25: 0000000000000400 x24: ffff0000095567d4

if add

#if CONFIG_NR_DRAM_BANKS == 2
gd->ram_size += PHYS_SDRAM_2_SIZE;
#endif

in dram_init function ,It will stuck in uboot stage too.

int dram_init(void)
{
/* rom_pointer[1] contains the size of TEE occupies */
if (rom_pointer[1])
gd->ram_size = PHYS_SDRAM_SIZE - rom_pointer[1];
else
gd->ram_size = PHYS_SDRAM_SIZE;

#if CONFIG_NR_DRAM_BANKS == 2
gd->ram_size += PHYS_SDRAM_2_SIZE;
#endif

return 0;
}

U-Boot 2019.04-4.19.35-1.1.0+g718e897 (Nov 12 2020 - 02:23:21 +0000)

CPU: Freescale i.MX8MQ rev2.1 1300 MHz (running at 800 MHz)
CPU: Industrial temperature grade (-40C to 105C) at 45C
Reset cause: POR
Model: Freescale i.MX8MQ EVK
DRAM:

I don’t know what is the difference between IMX8MM and IMX8MQ in 4G LPDDR4, can anyone give some suggestions to adapt IMX8MQ to 4G LPDDR4

Re: IMX8MQ replace 4G lpddr4 issue

igorpadykov — Thu, 12 Nov 2020 04:08:45 GMT

Hi coindu

one can try to remove OPTee as described in sect.5.6.11 OP-TEE enablement

Yocto Guide included in Documentation

also please check if attached patch is applied in that case.

Best regards
igor

Re: IMX8MQ replace 4G lpddr4 issue

kanimozhi_t — Thu, 11 Feb 2021 06:04:15 GMT

@igorpadykov thanks for the details.

But I would like to know how can I enable OPTEE with 4GB RAM?

topic Re: IMX8MQ replace 4G lpddr4 issue in i.MX Processors

IMX8MQ replace 4G lpddr4 issue

Re: IMX8MQ replace 4G lpddr4 issue

Re: IMX8MQ replace 4G lpddr4 issue