[PATCH] TXx9: Add TX4939 RNG support

[PATCH] TXx9: Add TX4939 RNG support

[Atsushi Nemoto]

Add platform support for RNG of TX4939 SoC.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
---
 arch/mips/include/asm/txx9/tx4939.h   |    1 +
 arch/mips/txx9/generic/setup_tx4939.c |   18 ++++++++++++++++++
 arch/mips/txx9/rbtx4939/setup.c       |    1 +
 3 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/arch/mips/include/asm/txx9/tx4939.h b/arch/mips/include/asm/txx9/tx4939.h
index 050364d..3451499 100644
--- a/arch/mips/include/asm/txx9/tx4939.h
+++ b/arch/mips/include/asm/txx9/tx4939.h
@@ -547,5 +547,6 @@ void tx4939_ndfmc_init(unsigned int hold, unsigned int spw,
 void tx4939_dmac_init(int memcpy_chan0, int memcpy_chan1);
 void tx4939_aclc_init(void);
 void tx4939_sramc_init(void);
+void tx4939_rng_init(void);
 
 #endif /* __ASM_TXX9_TX4939_H */
diff --git a/arch/mips/txx9/generic/setup_tx4939.c b/arch/mips/txx9/generic/setup_tx4939.c
index df13a89..4b7293c 100644
--- a/arch/mips/txx9/generic/setup_tx4939.c
+++ b/arch/mips/txx9/generic/setup_tx4939.c
@@ -500,6 +500,24 @@ void __init tx4939_sramc_init(void)
 		txx9_sramc_init(&tx4939_sram_resource);
 }
 
+#define TX4939_RNG_REG	((TX4939_CRYPTO_REG & 0xfffffffffULL) + 0xb0)
+void __init tx4939_rng_init(void)
+{
+	static struct resource res = {
+		.start = TX4939_RNG_REG,
+		.end = TX4939_RNG_REG + 0x30 - 1,
+		.flags = IORESOURCE_MEM,
+	};
+	static struct platform_device pdev = {
+		.name = "tx4939-rng",
+		.id = -1,
+		.num_resources = 1,
+		.resource = &res,
+	};
+
+	platform_device_register(&pdev);
+}
+
 static void __init tx4939_stop_unused_modules(void)
 {
 	__u64 pcfg, rst = 0, ckd = 0;
diff --git a/arch/mips/txx9/rbtx4939/setup.c b/arch/mips/txx9/rbtx4939/setup.c
index b919696..c033ffe 100644
--- a/arch/mips/txx9/rbtx4939/setup.c
+++ b/arch/mips/txx9/rbtx4939/setup.c
@@ -502,6 +502,7 @@ static void __init rbtx4939_device_init(void)
 	tx4939_aclc_init();
 	platform_device_register_simple("txx9aclc-generic", -1, NULL, 0);
 	tx4939_sramc_init();
+	tx4939_rng_init();
 }
 
 static void __init rbtx4939_setup(void)
-- 
1.5.6.5

Re: [PATCH] TXx9: Add TX4939 RNG support

[Atsushi Nemoto]

: This is a reply for comments from Matt Mackall via mm-commit mail.

On Fri, 29 May 2009 19:21:22 -0500, Matt Mackall <mpm@selenic.com> wrote:
> > +++ a/arch/mips/txx9/generic/setup_tx4939.c
> > @@ -494,6 +494,24 @@ void __init tx4939_aclc_init(void)
> >  			       TXX9_IRQ_BASE + TX4939_IR_ACLC, 1, 0, 1);
> >  }
> >  
> > +#define TX4939_RNG_REG	((TX4939_CRYPTO_REG & 0xfffffffffULL) + 0xb0)
> 
> This isn't the best place for this define?

Well, I can move it to include/asm/txx9/tx4939.h.

> > +++ a/arch/mips/txx9/rbtx4939/setup.c
> > @@ -501,6 +501,7 @@ static void __init rbtx4939_device_init(
> >  	tx4939_dmac_init(0, 2);
> >  	tx4939_aclc_init();
> >  	platform_device_register_simple("txx9aclc-generic", -1, NULL, 0);
> > +	tx4939_rng_init();
> >  }
> >  
> >  static void __init rbtx4939_setup(void)
> 
> Not clear to me how this works when this is a module?

This patch add a registration of a platform device for RNG to vmlinux.
And the other patch add a driver module for the RNG.  This strategy is
fairly common for SoCs or embedded platforms.

---
Atsushi Nemoto

Re: [PATCH] TXx9: Add TX4939 RNG support

[Matt Mackall]

On Mon, 2009-06-01 at 01:57 +0900, Atsushi Nemoto wrote:
> : This is a reply for comments from Matt Mackall via mm-commit mail.
> 
> On Fri, 29 May 2009 19:21:22 -0500, Matt Mackall <mpm@selenic.com> wrote:
> > > +++ a/arch/mips/txx9/generic/setup_tx4939.c
> > > @@ -494,6 +494,24 @@ void __init tx4939_aclc_init(void)
> > >  			       TXX9_IRQ_BASE + TX4939_IR_ACLC, 1, 0, 1);
> > >  }
> > >  
> > > +#define TX4939_RNG_REG	((TX4939_CRYPTO_REG & 0xfffffffffULL) + 0xb0)
> > 
> > This isn't the best place for this define?
> 
> Well, I can move it to include/asm/txx9/tx4939.h.
> 
> > > +++ a/arch/mips/txx9/rbtx4939/setup.c
> > > @@ -501,6 +501,7 @@ static void __init rbtx4939_device_init(
> > >  	tx4939_dmac_init(0, 2);
> > >  	tx4939_aclc_init();
> > >  	platform_device_register_simple("txx9aclc-generic", -1, NULL, 0);
> > > +	tx4939_rng_init();
> > >  }
> > >  
> > >  static void __init rbtx4939_setup(void)
> > 
> > Not clear to me how this works when this is a module?
> 
> This patch add a registration of a platform device for RNG to vmlinux.
> And the other patch add a driver module for the RNG.  This strategy is
> fairly common for SoCs or embedded platforms.

If your driver is built as a module (which your patch allows), the above
won't work, right?

-- 
http://selenic.com : development and support for Mercurial and Linux

Re: [PATCH] TXx9: Add TX4939 RNG support

[Atsushi Nemoto]

On Sun, 31 May 2009 12:01:29 -0500, Matt Mackall <mpm@selenic.com> wrote:
> > > Not clear to me how this works when this is a module?
> > 
> > This patch add a registration of a platform device for RNG to vmlinux.
> > And the other patch add a driver module for the RNG.  This strategy is
> > fairly common for SoCs or embedded platforms.
> 
> If your driver is built as a module (which your patch allows), the above
> won't work, right?

No, the rng driver can be used regardless of module or built-in, as
like as other platform drivers.  Any special issue for hw_rng?

---
Atsushi Nemoto

Re: [PATCH] TXx9: Add TX4939 RNG support

[Matt Mackall]

On Mon, 2009-06-01 at 02:23 +0900, Atsushi Nemoto wrote:
> On Sun, 31 May 2009 12:01:29 -0500, Matt Mackall <mpm@selenic.com> wrote:
> > > > Not clear to me how this works when this is a module?
> > > 
> > > This patch add a registration of a platform device for RNG to vmlinux.
> > > And the other patch add a driver module for the RNG.  This strategy is
> > > fairly common for SoCs or embedded platforms.
> > 
> > If your driver is built as a module (which your patch allows), the above
> > won't work, right?
> 
> No, the rng driver can be used regardless of module or built-in, as
> like as other platform drivers.  Any special issue for hw_rng?

I found the source of my confusion: you've given the init function in
both files exactly the same name. So when I saw .._init at the bottom of
the second patch, I assumed it was referring to the possibly not loaded
driver's init code.

-- 
http://selenic.com : development and support for Mercurial and Linux

Re: [PATCH] TXx9: Add TX4939 RNG support

[Atsushi Nemoto]

On Sun, 31 May 2009 12:32:50 -0500, Matt Mackall <mpm@selenic.com> wrote:
> > No, the rng driver can be used regardless of module or built-in, as
> > like as other platform drivers.  Any special issue for hw_rng?
> 
> I found the source of my confusion: you've given the init function in
> both files exactly the same name. So when I saw .._init at the bottom of
> the second patch, I assumed it was referring to the possibly not loaded
> driver's init code.

OK, I see.  I will rename one of them to avoid such a confusion.
Thanks.

---
Atsushi Nemoto