MPC5xxx中的主题 Re: Flexray memory access Issue

Flexray memory access Issue

stefintomy — Thu, 04 Aug 2016 08:58:27 GMT

While trying to access flexray memory from Z6 ,it hit on IVOR13 (Data TLB error).Is there any configuration changes required to access those registers from Z6?

from Z0 it is possible to access such registers.

Re: Flexray memory access Issue

lukaszadrapa — Thu, 04 Aug 2016 11:33:29 GMT

Hi,

on MPC5668G the Flexray module is connected to peripheral bridge B. This MMU space is not initialized by the BAM after reset and hence must be configured by user software at startup before the peripherals on the bridge can be accessed. This was done on as we did not want the risk associated with making a change to the BAM code. See the code below how to initialize MMU to cover the peripheral bridge.

#TLB4 = pbridgeA

lis r3, 0x1004

mtmas0 r3

lis r3, 0xC000

ori r3, r3, 0x0800

mtmas1 r3

lis r3, 0xC000

ori r3, r3, 0x000A

mtmas2 r3

lis r3, 0xC000

ori r3, r3, 0x003F

mtmas3 r3

tlbwe

This will initialize TLB entry 4. You can take a look at Table 8-3 in reference manual (page 247-248) where the default MMU configuration can be found.

Regards,

Lukas

Re: Flexray memory access Issue

stefintomy — Thu, 04 Aug 2016 15:22:02 GMT

my tlb is this:-

TlbWrite:

e_lis r3,__MAS_CONFIG_START@h

e_or2i r3,__MAS_CONFIG_START@l

e_lis r0,__MAS_CONFIG_SIZE@h

e_or2i r0,__MAS_CONFIG_SIZE@l

mtctr r0

tlbloop:

se_lwz r4,0(r3)

mtspr 624,r4

se_lwz r4,4(r3)

mtspr 625,r4

se_lwz r4,8(r3)

mtspr 626,r4

se_lwz r4,12(r3)

mtspr 627,r4

lis r4,0x1000

ori r4,r4,0x011E

mtspr 628,r4

lis r4,0x0

ori r4,r4,0x0

mtspr 630,r4

tlbwe

addi r3,r3,16

bdnz tlbloop

in dld:-

__MAS_CONFIG_START = .;

STORE (0x10030000, 4) STORE (0xC0000500, 4) STORE (0x40000028, 4) STORE (0x4000003F, 4)

STORE (0x10040000, 4) STORE (0xC0000400, 4) STORE (0x00000028, 4) STORE (0x0000003F, 4)

STORE (0x10050000, 4) STORE (0xC0000400, 4) STORE (0x00040020, 4) STORE (0x0004003F, 4)

STORE (0x10060000, 4) STORE (0xC0000400, 4) STORE (0x00080020, 4) STORE (0x0008003F, 4)

STORE (0x10070000, 4) STORE (0xC0000400, 4) STORE (0x000C0000, 4) STORE (0x000C003F, 4)

STORE (0x10080000, 4) STORE (0xC0000500, 4) STORE (0x00100000, 4) STORE (0x0010003F, 4)

STORE (0x10010000, 4) STORE (0x00000900, 4) STORE (0x00000020, 4) STORE (0x0000003F, 4)

STORE (0x10000000, 4) STORE (0xC0000500, 4) STORE (0xFFF0002A, 4) STORE (0xFFF0003F, 4)

__MAS_CONFIG_END = .;

__MAS_CONFIG_SIZE = (__MAS_CONFIG_END - __MAS_CONFIG_START)/16;

i tried to make changes as you said but didn't succeed. could you please look into this....