Re: [PATCH 1/2] mmc: sh_mmcif: double clock speed
Hi Simon On Wed, 21 Mar 2012, Simon Horman wrote: This corrects an off-by one error when calculating the clock divisor. The code previously assumed that for example a divisor of 2 is set using a value of 0001 (the inverse of 1/2), a divisor of 4 is set using a value of 0010 (the inverse of 1/4) etc.. However, the correct values are , 0001, etc... The use of DIV_ROUND_UP() was suggested by Guennadi Liakhovetski to avoid understating the divisor by one in the case where the host clock is not a binary power of the MMCIF clock. The patch looks good, but the commit message is not quite right. Cases of host-clk / clk != 2^n are handled by using fls(x - 1) instead of fls(x) - 1, as you initially suggested. DIV_ROUND_UP() is needed for divisions with a residue. E.g., for host clock 13MHz, target clock 3MHz you want a divisor of 5, resulting in 2 16, not 4, resulting in 1 16. With this fixed Acked-by: Guennadi Liakhovetski g.liakhovet...@gmx.de Thanks Guennadi Cc: Guennadi Liakhovetski g.liakhovet...@gmx.de Tested-by: Cao Minh Hiep hie...@gmail.com Signed-off-by: Simon Horman ho...@verge.net.au --- drivers/mmc/host/sh_mmcif.c |3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c index 8057bf3..5014bc4 100644 --- a/drivers/mmc/host/sh_mmcif.c +++ b/drivers/mmc/host/sh_mmcif.c @@ -453,7 +453,8 @@ static void sh_mmcif_clock_control(struct sh_mmcif_host *host, unsigned int clk) sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_SUP_PCLK); else sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR - ((fls(host-clk / clk) - 1) 16)); + ((fls(DIV_ROUND_UP(host-clk, +clk) - 1) - 1) 16)); sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_ENABLE); } -- 1.7.6.3 --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line unsubscribe linux-mmc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 2/2] mmc: sh_mmcif: mmc-f_max should be half of the bus clock
On Wed, 21 Mar 2012, Simon Horman wrote: mmc-f_max should be half of the bus clock. And now that mmc-f_max is not equal to the bus clock the latter should be used directly to calculate mmc-f_min. The patch seems correct as it stands, however, looking at it - does anyone understands why that close to 400kHz comment and such a complicated calculation? Shouldn't it be just host-clk / 512 always? Maybe this should be a separate patch, so, for this one Acked-by: Guennadi Liakhovetski g.liakhovet...@gmx.de Thanks Guennadi Cc: Guennadi Liakhovetski g.liakhovet...@gmx.de Tested-by: Cao Minh Hiep hie...@gmail.com Signed-off-by: Simon Horman ho...@verge.net.au --- drivers/mmc/host/sh_mmcif.c | 12 ++-- 1 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c index 5014bc4..1410baa 100644 --- a/drivers/mmc/host/sh_mmcif.c +++ b/drivers/mmc/host/sh_mmcif.c @@ -1297,14 +1297,14 @@ static int __devinit sh_mmcif_probe(struct platform_device *pdev) spin_lock_init(host-lock); mmc-ops = sh_mmcif_ops; - mmc-f_max = host-clk; + mmc-f_max = host-clk / 2; /* close to 400KHz */ - if (mmc-f_max 5120) - mmc-f_min = mmc-f_max / 128; - else if (mmc-f_max 10240) - mmc-f_min = mmc-f_max / 256; + if (host-clk 5120) + mmc-f_min = host-clk / 128; + else if (host-clk 10240) + mmc-f_min = host-clk / 256; else - mmc-f_min = mmc-f_max / 512; + mmc-f_min = host-clk / 512; if (pd-ocr) mmc-ocr_avail = pd-ocr; mmc-caps = MMC_CAP_MMC_HIGHSPEED; -- 1.7.6.3 --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line unsubscribe linux-mmc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 4/4] arm: at91: dt: sam9g25ek add mci support
On Thu, 22 Mar 2012 15:53:01 +0100, Nicolas Ferre nicolas.fe...@atmel.com
wrote:
On 03/21/2012 07:03 PM, ludovic.desroc...@atmel.com :
From: Ludovic Desroches ludovic.desroc...@atmel.com
Signed-off-by: Ludovic Desroches ludovic.desroc...@atmel.com
Signed-off-by: Nicolas Ferre nicolas.fe...@atmel.com
I think you really mean Acked-by. It is only appropriate to add a
Signed-off-by tag when you have actually picked up and either
committed or reposted a patch. When replying to a patch on the
mailing list and giving your okay, the correct tag is either
Acked-by or Reviewed-by (The difference being that Acked-by
infers that you have some authority over the areas touched by the
patch).
See Documentation/SubmittingPatches
g.
---
arch/arm/boot/dts/at91sam9g25ek.dts | 16
1 files changed, 16 insertions(+), 0 deletions(-)
diff --git a/arch/arm/boot/dts/at91sam9g25ek.dts
b/arch/arm/boot/dts/at91sam9g25ek.dts
index 7a13d09..960de2b 100644
--- a/arch/arm/boot/dts/at91sam9g25ek.dts
+++ b/arch/arm/boot/dts/at91sam9g25ek.dts
@@ -32,6 +32,22 @@
phy-mode = rmii;
status = okay;
};
+
+ mmc0: mmc@f0008000 {
+ status = okay;
+ slot@0 {
+ bus-width = 4;
+ cd-gpios = pioD 15 0;
+ };
+ };
+
+ mmc1: mmc@f000c000 {
+ status = okay;
+ slot@0 {
+ bus-width = 4;
+ cd-gpios = pioD 14 0;
+ };
+ };
};
usb0: ohci@0060 {
--
Nicolas Ferre
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