Re: [U-Boot] fdt performance

2014-01-26 Thread Simon Glass
Hi Aaron, On 13 January 2014 23:13, Aaron Williams wrote: > Hi Simon, > > Sorry for the long delay. > > > > On 10/17/2013 03:27 PM, Simon Glass wrote: >> >> Hi Aaron, >> >> On Thu, Oct 17, 2013 at 12:24 AM, Aaron Williams >> wrote: >>> >>> Hi all, >>> >>> In our bootloader based off of 2013.07 w

Re: [U-Boot] fdt performance

2014-01-13 Thread Aaron Williams
Hi Simon, Sorry for the long delay. On 10/17/2013 03:27 PM, Simon Glass wrote: Hi Aaron, On Thu, Oct 17, 2013 at 12:24 AM, Aaron Williams wrote: Hi all, In our bootloader based off of 2013.07 we make extensive use of the flat device tree. In profiling our bootloader in our simulator I foun

Re: [U-Boot] fdt performance

2013-11-14 Thread Simon Glass
Hi Scott, On Thu, Nov 14, 2013 at 4:36 PM, Scott Wood wrote: > On Thu, 2013-10-17 at 16:27 -0600, Simon Glass wrote: > > Hi Aaron, > > > > On Thu, Oct 17, 2013 at 12:24 AM, Aaron Williams > > wrote: > > > Hi all, > > > > > > In our bootloader based off of 2013.07 we make extensive use of the >

Re: [U-Boot] fdt performance

2013-11-14 Thread Scott Wood
On Thu, 2013-10-17 at 16:27 -0600, Simon Glass wrote: > Hi Aaron, > > On Thu, Oct 17, 2013 at 12:24 AM, Aaron Williams > wrote: > > Hi all, > > > > In our bootloader based off of 2013.07 we make extensive use of the flat > > device tree. In profiling our bootloader in our simulator I found that t

Re: [U-Boot] fdt performance

2013-10-22 Thread Wolfgang Denk
Dear Michael, In message you wrote: > > We seem to have a misunderstanding, I did not mean to imply that the > "offset + len" > expression was undefined. I agree that it is fine. I was referring > to this statement from > Aaron's original email: > > if (p + len < p) > > Which is fol

Re: [U-Boot] fdt performance

2013-10-22 Thread Michael Pratt
Hi Wolfgang, On Mon, Oct 21, 2013 at 3:55 PM, Wolfgang Denk wrote: > > Dear Michael, > > In message > you > wrote: > > > > > > it's possible that these checks could be simply optimised away. The > > > > > > This is not hwat happens. > > > > Actually, it is my understanding that the "if (p + le

Re: [U-Boot] fdt performance

2013-10-21 Thread Wolfgang Denk
Dear Michael, In message you wrote: > > > > it's possible that these checks could be simply optimised away. The > > > > This is not hwat happens. > > Actually, it is my understanding that the "if (p + len < p)" can be > optimized away. This exact case is discussed in the LWN article "GCC and >

Re: [U-Boot] fdt performance

2013-10-20 Thread Michael Pratt
Hi Wolfgang, On Fri, Oct 18, 2013 at 4:11 PM, Wolfgang Denk wrote: > Dear Andre, > > In message < > capfze3a2ne-xcjkutk8ws78v0yxusd50wsqvm1rspgnufwp...@mail.gmail.com> you > wrote: > > > > >> Some of the checks in fdt_offset_ptr also look useless, such as if > > >> ((offset + len) < offset) whic

Re: [U-Boot] fdt performance

2013-10-18 Thread Wolfgang Denk
Dear Andre, In message you wrote: > > >> Some of the checks in fdt_offset_ptr also look useless, such as if > >> ((offset + len) < offset) which will always be false, or > >> if (p + len < p) > > > > What happens if the "offset" or "p" point to addresses close to the > > upper end of the addres

Re: [U-Boot] fdt performance

2013-10-17 Thread Simon Glass
Hi Aaron, On Thu, Oct 17, 2013 at 12:24 AM, Aaron Williams wrote: > Hi all, > > In our bootloader based off of 2013.07 we make extensive use of the flat > device tree. In profiling our bootloader in our simulator I found that the > function eating up the most time is fdt_next_tag. Looking at it,

Re: [U-Boot] fdt performance

2013-10-17 Thread Andre Renaud
Hi Wolfgang, On 18 October 2013 07:55, Wolfgang Denk wrote: > In message <525f8284.4000...@caviumnetworks.com> you wrote: >> Some of the checks in fdt_offset_ptr also look useless, such as if >> ((offset + len) < offset) which will always be false, or >> if (p + len < p) > > What happens if the "

Re: [U-Boot] fdt performance

2013-10-17 Thread Wolfgang Denk
Dear Aaron Williams, In message <525f8284.4000...@caviumnetworks.com> you wrote: > > Some of the checks in fdt_offset_ptr also look useless, such as if > ((offset + len) < offset) which will always be false, or > if (p + len < p) What happens if the "offset" or "p" point to addresses close to t

Re: [U-Boot] fdt performance

2013-10-17 Thread Albert ARIBAUD
Hi Aaron, On Wed, 16 Oct 2013 23:24:04 -0700, Aaron Williams wrote: > Hi all, > > In our bootloader based off of 2013.07 we make extensive use of the flat > device tree. In profiling our bootloader in our simulator I found that > the function eating up the most time is fdt_next_tag. Looking a

[U-Boot] fdt performance

2013-10-16 Thread Aaron Williams
Hi all, In our bootloader based off of 2013.07 we make extensive use of the flat device tree. In profiling our bootloader in our simulator I found that the function eating up the most time is fdt_next_tag. Looking at it, especially fdt_offset_ptr, it looks like there is a lot of room for impr