Linux 2.6.12-rc6 Memory: 25k available (0k kernel code, 0k data, 0k init, 0k highmem) all zero size showing

Asked by RAMACHANDRA on 2018-10-03

Hai Sir,
I am using PowerPC 440GX Processor (Reference of OCOTEA Board), In that Board u-boot-2014.04 version and Linux-2.6.12-rc6 are using. This is purely custom board reference of IBM PPC 440GX
In current Board DDR2 is not working inside SoC controller issuing (Hardware part) that's why i am taken external SRAM (16MB)
External SRAM Address Rang (0x44000000 to 0x44ffffff) of 16MB
My U-Boot is running from from (0x44e00000 to 0x44ffffff and Stack pointer is 0x44d00000 onwords)
My Linux ZImage.bin is loading from 0x44000000
My Linux Extraction part is extracted from 0x44100000 and Virtual Address is 0xc4100000
I am taken KERNEL_START - 0xc4100000 physical address 0x44000000
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Memory: 25k available (0k kernel code, 0k data, 0k init, 0k highmem) all zero size showing
In my case DDR is not working in place 0f 0x00 i am taken 0x44000000
In mapin_ram(void) function the size is 8MB taken and v=0xc0100000 and p=0x44100000 taken
mapin_ram
{
for (; s < total_lowmem; s += PAGE_SIZE) {
  if ((char *) v >= _stext && (char *) v < etext)
   f = _PAGE_RAM_TEXT;
  else
   f = _PAGE_RAM;
  map_page(v, p, f);
  v += PAGE_SIZE;
  p += PAGE_SIZE;

}

pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
 extern int mem_init_done;
 extern void *early_get_page(void);
 static char caravel_cnt=0,k=1;
 int i;

 if (mem_init_done)
 {
  pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
 }
 else
 {
  pte = (pte_t *)early_get_page();
// printk("pte value:%08lx\n",pte); //caravel
  pte=(0x44000000+(caravel_cnt*0x100000)); //caravel0x1000
  printk("Before pte value:%08lx\n",pte); //caravel
  caravel_cnt++;
  if (pte>=0x44100000 || pte<=0x44300000)
  {
// break;
  }
  else
  {
   for(i=0;i<=1048;i++)
   {
// caravel_cnt++;
    clear_page(pte);
    pte=(pte+(i*0x1000)); //caravel
// printk("for pte value:%08lx\n",pte); //caravel
   }
  printk("after pte value:%08lx\n",pte); //caravel
  }
//caravel clear_page(0x44100000);
 }
 return pte;*/
}
As per my requirement i am changed this above code
My code is running in this locations is showed below

External SRAM Address Rang (0x44000000 to 0x44ffffff) of 16MB
My U-Boot is running from from (0x44e00000 to 0x44ffffff and Stack pointer is 0x44d00000 onwords)
My Linux ZImage.bin is loading from 0x44000000
My Linux Extraction part is extracted from 0x44100000 and Virtual Address is 0xc4100000
I am taken KERNEL_START - 0xc4100000 physical address 0x44000000

I have some below doubts are there:
1.I want read all 16MB data and each BSS and Kernel and data and init sections will automatic doing or only code size only is enough from (0x44000000 to 0x44fffffc) or(Kernel code:0x44000000 to 0x447ffffc) or (uboot:0x44a00000 to 0x44fffffc) how much memory will take and while reading BAD Pages occuring
2. Actually DDR2 is not working in my core but whatever 0x44000000 data is accessing in 0x00 onwords using TLB entries (Using this case i will read 0x0 what will happen)
3.How to establish this memory print function it is showing zero
Memory: 25k available (0k kernel code, 0k data, 0k init, 0k highmem) all zero size showing

Question information

Language:
English Edit question
Status:
Expired
For:
Ubuntu linux-source-2.6.12 Edit question
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Last query:
2018-10-03
Last reply:
2018-10-19
Manfred Hampl (m-hampl) said : #1

This is a support area for Ubuntu, but I cannot see any relationship between this question and Ubuntu (except that it mentions a certain Linux kernel version that was also used in Ubuntu more than 10 years ago).

Which operating system are you running on your device? Is it Ubuntu, and if yes, which release?

Launchpad Janitor (janitor) said : #2

This question was expired because it remained in the 'Needs information' state without activity for the last 15 days.