[U-Boot] [PATCH 3/3] ARM: bcm283x: Set memory map at run-time

Matthias Brugger matthias.bgg at gmail.com
Wed Oct 16 16:50:13 UTC 2019



On 27/09/2019 12:14, Alexander Graf wrote:
> 
> On 27.09.19 11:00, matthias.bgg at kernel.org wrote:
>> From: Matthias Brugger <mbrugger at suse.com>
>>
>> For bcm283x based on arm64 we also have to change the mm_region.
>> Add assign this in mach_cpu_init() so we can create now one binary
>> for RPi3 and RPi4.
>>
>> Signed-off-by: Matthias Brugger <mbrugger at suse.com>
>>
>> ---
>>
>>   arch/arm/mach-bcm283x/init.c          | 65 +++++++++++++++++++++++++--
>>   board/raspberrypi/rpi/lowlevel_init.S |  6 +++
>>   board/raspberrypi/rpi/rpi.c           | 45 -------------------
>>   3 files changed, 67 insertions(+), 49 deletions(-)
>>
>> diff --git a/arch/arm/mach-bcm283x/init.c b/arch/arm/mach-bcm283x/init.c
>> index 214e1078eb..f6c2946922 100644
>> --- a/arch/arm/mach-bcm283x/init.c
>> +++ b/arch/arm/mach-bcm283x/init.c
>> @@ -8,16 +8,68 @@
>>     #include <common.h>
>>   #include <dm/device.h>
>> +#ifdef CONFIG_ARM64
>> +#include <asm/armv8/mmu.h>
>> +#endif
>>     #define PDATA_BCM2835    0
>>   #define PDATA_BCM2836    1
>>   #define PDATA_BCM2837    2
>> -#define PDATA_BCM2838    3
>> +#define PDATA_BCM2711    3
> 
> 
> What is this change?
> 

Wrong patch, I will fix this in v2.

> 
>>     extern unsigned long rpi_bcm283x_base;
>>   +#ifdef CONFIG_ARM64
>> +extern struct mm_region *mem_map;
>> +
>> +static struct mm_region bcm283x_mem_map[] = {
>> +    {
>> +        .virt = 0x00000000UL,
>> +        .phys = 0x00000000UL,
>> +        .size = 0x3f000000UL,
>> +        .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
>> +             PTE_BLOCK_INNER_SHARE
>> +    }, {
>> +        .virt = 0x3f000000UL,
>> +        .phys = 0x3f000000UL,
>> +        .size = 0x01000000UL,
>> +        .attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
>> +             PTE_BLOCK_NON_SHARE |
>> +             PTE_BLOCK_PXN | PTE_BLOCK_UXN
>> +    }, {
>> +        /* List terminator */
>> +        0,
>> +    }
>> +};
>> +
>> +static struct mm_region bcm2711_mem_map[] = {
>> +    {
>> +        .virt = 0x00000000UL,
>> +        .phys = 0x00000000UL,
>> +        .size = 0xfe000000UL,
>> +        .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
>> +             PTE_BLOCK_INNER_SHARE
>> +    }, {
>> +        .virt = 0xfe000000UL,
>> +        .phys = 0xfe000000UL,
>> +        .size = 0x01800000UL,
>> +        .attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
>> +             PTE_BLOCK_NON_SHARE |
>> +             PTE_BLOCK_PXN | PTE_BLOCK_UXN
>> +    }, {
>> +        /* List terminator */
>> +        0,
>> +    }
>> +};
>> +#else
>> +struct mm_region {
>> +    /* dummy struct */
>> +};
>> +#endif
>> +
>>   struct bcm283x_pdata {
>>       unsigned long io_base;
>> +    struct mm_region *m_map;
>>   };
>>     struct bcm283x_pdata pdata_bcm283x[] = {
>> @@ -30,9 +82,11 @@ struct bcm283x_pdata pdata_bcm283x[] = {
>>   #ifdef CONFIG_ARM64
>>       [PDATA_BCM2837] = {
>>           .io_base = 0x3f000000,
>> +        .m_map = bcm283x_mem_map,
>>       },
>> -    [PDATA_BCM2838] = {
>> +    [PDATA_BCM2711] = {
>>           .io_base = 0xfe000000,
>> +        .m_map = bcm2711_mem_map
>>       },
>>   #endif
>>   };
>> @@ -45,8 +99,8 @@ static const struct udevice_id board_ids[] = {
>>       { .compatible = "brcm,bcm2835", .data = PDATA_BCM2835},
>>       { .compatible = "brcm,bcm2836", .data = PDATA_BCM2836},
>>       { .compatible = "brcm,bcm2837", .data = PDATA_BCM2837},
>> -    { .compatible = "brcm,bcm2838", .data = PDATA_BCM2838},
>> -    { .compatible = "brcm,bcm2711", .data = PDATA_BCM2838},
>> +    { .compatible = "brcm,bcm2838", .data = PDATA_BCM2711},
>> +    { .compatible = "brcm,bcm2711", .data = PDATA_BCM2711},
>>       { },
>>   };
>>   @@ -72,6 +126,9 @@ int mach_cpu_init(void)
>>           if (!ret) {
>>               pdat = pdata_bcm283x[of_match->data];
>>               rpi_bcm283x_base = pdat.io_base;
>> +#ifdef CONFIG_ARM64
>> +            mem_map = pdat.m_map;
>> +#endif
>>               break;
>>           }
>>   diff --git a/board/raspberrypi/rpi/lowlevel_init.S
>> b/board/raspberrypi/rpi/lowlevel_init.S
>> index fcb99ebef7..9786a5a4b3 100644
>> --- a/board/raspberrypi/rpi/lowlevel_init.S
>> +++ b/board/raspberrypi/rpi/lowlevel_init.S
>> @@ -23,6 +23,12 @@ fw_dtb_pointer:
>>       .word 0x0
>>   #endif
>>   +#ifdef CONFIG_ARM64
>> +.global mem_map
>> +mem_map:
>> +    .dword 0x0
>> +#endif
> 
> 
> Why does this live in .S?
> 

It took me some time but now I think I understand what happens.
rpi_bcm283x_base and mem_map are assigned in mach_cpu_init. My understanding is
that for this function holds the same as for board_init_f (from Readme):
- BSS is not available, so you cannot use global/static variables, only stack
variables and global_data

If we put the declaration of both variables in a source file, it will be put
into .bss and we won't be able to boot.

The whole low_level.S lives in text_rest, so if I add __attribute__ ((section
(".text"))) to the declaration of the variables in, let's say, init.c I get a
compiler warning but U-Boot works as expected.

So my question is now, how to proceed. I could add them in the global_data arch
struct. That would work for fine for rpi_bcm283x_base but would need to some
bigger changes for mem_map as this is used by armv8 code for all SoCs.

Any idea?

Regards,
Matthias

> Alex
> 
> 
>> +
>>   /*
>>    * Routine: save_boot_params (called after reset from start.S)
>>    * Description: save ATAG/FDT address provided by the firmware at boot time
>> diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c
>> index 9e0abdda31..cf1666ce5f 100644
>> --- a/board/raspberrypi/rpi/rpi.c
>> +++ b/board/raspberrypi/rpi/rpi.c
>> @@ -248,51 +248,6 @@ static uint32_t rev_scheme;
>>   static uint32_t rev_type;
>>   static const struct rpi_model *model;
>>   -#ifdef CONFIG_ARM64
>> -#ifndef CONFIG_BCM2711
>> -static struct mm_region bcm283x_mem_map[] = {
>> -    {
>> -        .virt = 0x00000000UL,
>> -        .phys = 0x00000000UL,
>> -        .size = 0x3f000000UL,
>> -        .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
>> -             PTE_BLOCK_INNER_SHARE
>> -    }, {
>> -        .virt = 0x3f000000UL,
>> -        .phys = 0x3f000000UL,
>> -        .size = 0x01000000UL,
>> -        .attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
>> -             PTE_BLOCK_NON_SHARE |
>> -             PTE_BLOCK_PXN | PTE_BLOCK_UXN
>> -    }, {
>> -        /* List terminator */
>> -        0,
>> -    }
>> -};
>> -#else
>> -static struct mm_region bcm283x_mem_map[] = {
>> -    {
>> -        .virt = 0x00000000UL,
>> -        .phys = 0x00000000UL,
>> -        .size = 0xfe000000UL,
>> -        .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
>> -             PTE_BLOCK_INNER_SHARE
>> -    }, {
>> -        .virt = 0xfe000000UL,
>> -        .phys = 0xfe000000UL,
>> -        .size = 0x01800000UL,
>> -        .attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
>> -             PTE_BLOCK_NON_SHARE |
>> -             PTE_BLOCK_PXN | PTE_BLOCK_UXN
>> -    }, {
>> -        /* List terminator */
>> -        0,
>> -    }
>> -};
>> -#endif
>> -struct mm_region *mem_map = bcm283x_mem_map;
>> -#endif
>> -
>>   int dram_init(void)
>>   {
>>       ALLOC_CACHE_ALIGN_BUFFER(struct msg_get_arm_mem, msg, 1);


More information about the U-Boot mailing list