[PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[Zhiqiang Hou]

From: Hou Zhiqiang <Zhiqiang.Hou@freescale.com>

Only the value PCIE_LTSSM_L0 stands for the link is up, instead
of >= PCIE_LTSSM_L0.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@freescale.com>
---
 arch/powerpc/sysdev/fsl_pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 610f472..1595f55 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -73,7 +73,7 @@ static int fsl_pcie_check_link(struct pci_controller *hose)
 					       PCIE_LTSSM, 4, &val);
 		else
 			early_read_config_dword(hose, 0, 0, PCIE_LTSSM, &val);
-		if (val < PCIE_LTSSM_L0)
+		if (val != PCIE_LTSSM_L0)
 			return 1;
 	} else {
 		struct ccsr_pci __iomem *pci = hose->private_data;
-- 
2.1.0.27.g96db324

RE: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[Zhiqiang Hou]

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Re: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[Scott Wood]

[cc list trimmed]

On Mon, 2016-02-01 at 03:57 +0000, Zhiqiang Hou wrote:
> Hi,
> 
> Any comments?

Only that it was submitted too late for the last merge window, and I have not
yet begun processing patches for the next one.  If you meant this to be a fix
important enough to go in outside the merge window, it's missing any statement
of what the actual symptoms are.

-Scott

> 
> > -----Original Message-----
> > From: Zhiqiang Hou [mailto:Zhiqiang.Hou@freescale.com]
> > Sent: 2016年1月4日 15:45
> > To: linuxppc-dev@lists.ozlabs.org; benh@kernel.crashing.org; 
> > paulus@samba.org;
> > mpe@ellerman.id.au
> > Cc: Scott Wood <scottwood@freescale.com>; akpm@linux-foundation.org;
> > robh@kernel.org; Mingkai.Hu@freescale.com; Hou Zhiqiang
> > <Zhiqiang.Hou@freescale.com>
> > Subject: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM
> > 
> > From: Hou Zhiqiang <Zhiqiang.Hou@freescale.com>
> > 
> > Only the value PCIE_LTSSM_L0 stands for the link is up, instead of >=
> > PCIE_LTSSM_L0.
> > 
> > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@freescale.com>
> > ---
> >  arch/powerpc/sysdev/fsl_pci.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
> > index
> > 610f472..1595f55 100644
> > --- a/arch/powerpc/sysdev/fsl_pci.c
> > +++ b/arch/powerpc/sysdev/fsl_pci.c
> > @@ -73,7 +73,7 @@ static int fsl_pcie_check_link(struct pci_controller
> > *hose)
> >  					       PCIE_LTSSM, 4, &val);
> >  		else
> >  			early_read_config_dword(hose, 0, 0, PCIE_LTSSM,
> > &val);
> > -		if (val < PCIE_LTSSM_L0)
> > +		if (val != PCIE_LTSSM_L0)
> >  			return 1;
> >  	} else {
> >  		struct ccsr_pci __iomem *pci = hose->private_data;
> > --
> > 2.1.0.27.g96db324
> 
> Thanks,
> Zhiqiang
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev

Re: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[Edward L Swarthout]

From: Scott Wood:
>On Mon, 2016-02-01 at 03:57 +0000, Zhiqiang Hou wrote:
>> Any comments?
>
> Only that it was submitted too late for the last merge window, and I have=
 not
> yet begun processing patches for the next one.  If you meant this to be a=
 fix
> important enough to go in outside the merge window, it's missing any stat=
ement
> of what the actual symptoms are.
>
> > -----Original Message-----
> > From: Zhiqiang Hou [mailto:Zhiqiang.Hou@freescale.com]
> > To: linuxppc-dev@lists.ozlabs.org; benh@kernel.crashing.org;
> > Subject: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM
> >
> > Only the value PCIE_LTSSM_L0 stands for the link is up, instead of >=3D
> > PCIE_LTSSM_L0.
> >
> > diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pc=
i.c
> > @@ -73,7 +73,7 @@ static int fsl_pcie_check_link(struct pci_controller
> >                     early_read_config_dword(hose, 0, 0, PCIE_LTSSM,
> > -           if (val < PCIE_LTSSM_L0)
> > +           if (val !=3D PCIE_LTSSM_L0)
> >                     return 1;

This patch is incorrect as there are actually two states L0 and L0s (standb=
y)=20
that indicate an active link (a LTSSM value of 0x11 or  0x12).

The next user manual revision should contain this detail.

Ed

Re: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM

[Scott Wood]

On Wed, 2016-02-03 at 21:32 +0000, Edward L Swarthout wrote:
> From: Scott Wood:
> > On Mon, 2016-02-01 at 03:57 +0000, Zhiqiang Hou wrote:
> > > Any comments?
> > 
> > Only that it was submitted too late for the last merge window, and I have
> > not
> > yet begun processing patches for the next one.  If you meant this to be a
> > fix
> > important enough to go in outside the merge window, it's missing any
> > statement
> > of what the actual symptoms are.
> > 
> > > -----Original Message-----
> > > From: Zhiqiang Hou [mailto:Zhiqiang.Hou@freescale.com]
> > > To: linuxppc-dev@lists.ozlabs.org; benh@kernel.crashing.org;
> > > Subject: [PATCH] powerpc/fsl-pci: Correct the comparison of the LTSSM
> > > 
> > > Only the value PCIE_LTSSM_L0 stands for the link is up, instead of >=
> > > PCIE_LTSSM_L0.
> > > 
> > > diff --git a/arch/powerpc/sysdev/fsl_pci.c
> > > b/arch/powerpc/sysdev/fsl_pci.c
> > > @@ -73,7 +73,7 @@ static int fsl_pcie_check_link(struct pci_controller
> > >                     early_read_config_dword(hose, 0, 0, PCIE_LTSSM,
> > > -           if (val < PCIE_LTSSM_L0)
> > > +           if (val != PCIE_LTSSM_L0)
> > >                     return 1;
> 
> This patch is incorrect as there are actually two states L0 and L0s
> (standby) 
> that indicate an active link (a LTSSM value of 0x11 or  0x12).
> 
> The next user manual revision should contain this detail.

The next manual of what chip?

Are there any non-active states for which the current test does not work?

-Scott