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scripts: gen_mmu: Rectified MMU page table generation.

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The script failed on certain corner cases. Whenever the memory region
was falling on the PDE boundary, the glitch was causing incorrect
PTE to be generated.

JIRA: ZEP-2328

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
This commit is contained in:
Adithya Baglody 2017-07-01 13:23:58 +05:30 • committed by Anas Nashif
commit 5ffffb86bf
1 changed files with 28 additions and 27 deletions
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55
scripts/gen_mmu.py
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@ -132,7 +132,7 @@ def read_mmu_list_marshal_param():
# in case where it overflows the currenty PDE's range then limit the
# PTE to 1024 and so make the mem_size reflect the actual size taken up
# in the current PDE
if (region[1] + (pte_valid_addr_start * 4096) ) > (1024*4096):
if (region[1] + (pte_valid_addr_start * 4096) ) >= (1024*4096):
pte_valid_addr_end = 1024
mem_size = ( (pte_valid_addr_end - pte_valid_addr_start)*4096)
@ -157,40 +157,41 @@ def read_mmu_list_marshal_param():
# create all the extra PDEs needed to fit the requested size
# this loop starts from the current pde till the last pde that is needed
# the last pde is calcualted as the (start_addr + size) >> 22
for extra_pde in range(pde_index+1, get_pde_number(
region[0] + region[1])+1):
if overflow_size !=0:
for extra_pde in range(pde_index+1, get_pde_number(
region[0] + region[1])+1):
# new pde's start address
# each page directory entry has a addr range of (1024 *4096)
# thus the new PDE start address is a multiple of that number
extra_pde_start_address = extra_pde*(4096*1024)
# new pde's start address
# each page directory entry has a addr range of (1024 *4096)
# thus the new PDE start address is a multiple of that number
extra_pde_start_address = extra_pde*(4096*1024)
# the start address of and extra pde will always be 0
# and the end address is calculated with the new pde's start address
# and the overflow_size
extra_pte_valid_addr_end = get_pte_number(extra_pde_start_address
+ overflow_size)
# the start address of and extra pde will always be 0
# and the end address is calculated with the new pde's start address
# and the overflow_size
extra_pte_valid_addr_end = get_pte_number(extra_pde_start_address
+ overflow_size)
# if the overflow_size couldn't be fit inside this new pde then
# need another pde and so we now need to limit the end of the PTE
# to 1024 and set the size of this new region to the max possible
extra_region_size = overflow_size
if overflow_size > (1024*4096):
extra_region_size = 1024*4096
extra_pte_valid_addr_end = 1024
# if the overflow_size couldn't be fit inside this new pde then
# need another pde and so we now need to limit the end of the PTE
# to 1024 and set the size of this new region to the max possible
extra_region_size = overflow_size
if overflow_size > (1024*4096):
extra_region_size = 1024*4096
extra_pte_valid_addr_end = 1024
# load the new PDE's details
# load the new PDE's details
set_pde_pte_values(extra_pde, extra_pde_start_address,
extra_region_size,
0, extra_pte_valid_addr_end, region[2] )
set_pde_pte_values(extra_pde, extra_pde_start_address,
extra_region_size,
0, extra_pte_valid_addr_end, region[2] )
# for the next iteration of the loop the size needs to decreased
overflow_size -= (extra_pte_valid_addr_end) * 4096
# for the next iteration of the loop the size needs to decreased
overflow_size -= (extra_pte_valid_addr_end) * 4096
if extra_pde not in page_tables_list:
page_tables_list.append(extra_pde)
if extra_pde not in page_tables_list:
page_tables_list.append(extra_pde)
page_tables_list.sort()