[U-Boot] Reset Status on MPC83xx
In an effort to find the cause of reboot from linux userspace, which was always returning hardreset, i traced the reason for the reset status register being cleared is from file arch/powerpc/cpu/mpc83xx/cpu_init.c,
/* RSR - Reset Status Register - clear all status (4.6.1.3) */ gd->reset_status = __raw_readl(&im->reset.rsr); __raw_writel(~(RSR_RES), &im->reset.rsr);
Can anyone throw some light why it is getting cleared and what is 4.6.1.3
Thanks S
Dear Sridhar Addagada,
In message 1324360794.59571.YahooMailNeo@web120203.mail.ne1.yahoo.com you wrote:
In an effort to find the cause of reboot from linux userspace, which was always returning hardreset, i traced the reason for the reset status register being cleared is from file arch/powerpc/cpu/mpc83xx/cpu_init.c,
/* RSR - Reset Status Register - clear all status (4.6.1.3) */ gd->reset_status __raw_readl(&im->reset.rsr); __raw_writel(~(RSR_RES), &im->reset.rsr);
Can anyone throw some light why it is getting cleared and what is 4.6.1.3
"(4.6.1.3)" usually means the relevant section in the respective user's manual (MPC8349E PowerQUICC II Pro Integrated Host Processor Family Reference Manual, Rev. 1), here section "4.6.1.3 Reset Status Register (RSR)" on page 4-37 ff.
The Note also explains why it makes sense to clear the register (so you can get a sane state for only the next reset/reboot).
Best regards,
Wolfgang Denk
Thought so, i was looking at the wrong manual 837x, hence did not find the section
Thanks S
________________________________ From: Wolfgang Denk wd@denx.de To: Sridhar Addagada sridhar_a@yahoo.com Cc: "u-boot@lists.denx.de" u-boot@lists.denx.de Sent: Tuesday, December 20, 2011 5:18 PM Subject: Re: [U-Boot] Reset Status on MPC83xx
Dear Sridhar Addagada,
In message 1324360794.59571.YahooMailNeo@web120203.mail.ne1.yahoo.com you wrote:
In an effort to find the cause of reboot from linux userspace, which was always returning hardreset, i traced the reason for the reset status register being cleared is from file arch/powerpc/cpu/mpc83xx/cpu_init.c,
/* RSR - Reset Status Register - clear all status (4.6.1.3) */ gd->reset_status __raw_readl(&im->reset.rsr); __raw_writel(~(RSR_RES), &im->reset.rsr);
Can anyone throw some light why it is getting cleared and what is 4.6.1.3
"(4.6.1.3)" usually means the relevant section in the respective user's manual (MPC8349E PowerQUICC II Pro Integrated Host Processor Family Reference Manual, Rev. 1), here section "4.6.1.3 Reset Status Register (RSR)" on page 4-37 ff.
The Note also explains why it makes sense to clear the register (so you can get a sane state for only the next reset/reboot).
Best regards,
Wolfgang Denk
participants (2)
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Sridhar Addagada -
Wolfgang Denk