[PATCH 0/5] arm: sa1100: fix sa1100 fb and pcmcia w/o cpufreq

[PATCH 0/5] arm: sa1100: fix sa1100 fb and pcmcia w/o cpufreq

[Dmitry Eremin-Solenikov]

Hello,

These patches were sitting in my queue for some time. On SA-1100
framebuffer and PCMCIA drivers make use of cpufreq_get(0) function call
to determine the cpu frequency. Russell's commit
1937f5b91833e2e8e53bcc821fc7a5fbe6ccb9b5 (ARM: fix sa1100 build) fixed
the build issues, but broke two devices (Collie and Jornada720). For
those two boards the cpufreq code gets compiled but is not enabled (as
board files do not provide timing information for the CPUFREQ driver).
Thus cpufreq_get(0) returns incorrect values and incorrect timings get
programmed into the hardware.

PXA2xx (the very similar platform) uses Clock API to determine CPU
frequency both in framebuffer and PCMCIA drivers. These patches make
similar changes to StrongARM drivers.

These patches are required to make use of framebuffer and CF card on
Sharp Collie (and possibly on HP Jornada 720).

-- 
With best wishes
Dmitry

[PATCH 1/5] arm: sa1100: add cpu clock

[Dmitry Eremin-Solenikov]

Both SA1100 framebuffer and PCMCIA drivers require knowledge of cpu
frequency to correctly program timings.  Currently they receive timing
information by calling cpufreq_get(0).  However if cpu frequency driver
is not enabled (e.g. due to unsupported DRAM chip/board on sa1110)
cpufreq_get(0) returns 0, causing incorrect timings to be programmed.

Add cpu clock returning cpu frequency, to be used by sa11x0 fb and
pcmcia drivers.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 arch/arm/mach-sa1100/clock.c | 41 ++++++++++++++++++++++++++++++++++-------
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
index 9fa6a99..53f750d 100644
--- a/arch/arm/mach-sa1100/clock.c
+++ b/arch/arm/mach-sa1100/clock.c
@@ -15,10 +15,12 @@
 #include <linux/clkdev.h>
 
 #include <mach/hardware.h>
+#include <mach/generic.h>
 
 struct clkops {
 	void			(*enable)(struct clk *);
 	void			(*disable)(struct clk *);
+	unsigned long		(*get_rate)(struct clk *);
 };
 
 struct clk {
@@ -33,13 +35,6 @@ struct clk clk_##_name = {				\
 
 static DEFINE_SPINLOCK(clocks_lock);
 
-/* Dummy clk routine to build generic kernel parts that may be using them */
-unsigned long clk_get_rate(struct clk *clk)
-{
-	return 0;
-}
-EXPORT_SYMBOL(clk_get_rate);
-
 static void clk_gpio27_enable(struct clk *clk)
 {
 	/*
@@ -58,6 +53,19 @@ static void clk_gpio27_disable(struct clk *clk)
 	GAFR &= ~GPIO_32_768kHz;
 }
 
+static void clk_cpu_enable(struct clk *clk)
+{
+}
+
+static void clk_cpu_disable(struct clk *clk)
+{
+}
+
+static unsigned long clk_cpu_get_rate(struct clk *clk)
+{
+	return sa11x0_getspeed(0) * 1000;
+}
+
 int clk_enable(struct clk *clk)
 {
 	unsigned long flags;
@@ -87,16 +95,35 @@ void clk_disable(struct clk *clk)
 }
 EXPORT_SYMBOL(clk_disable);
 
+unsigned long clk_get_rate(struct clk *clk)
+{
+	if (clk && clk->ops && clk->ops->get_rate)
+		return clk->ops->get_rate(clk);
+
+	return 0;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
 const struct clkops clk_gpio27_ops = {
 	.enable		= clk_gpio27_enable,
 	.disable	= clk_gpio27_disable,
 };
 
+const struct clkops clk_cpu_ops = {
+	.enable		= clk_cpu_enable,
+	.disable	= clk_cpu_disable,
+	.get_rate	= clk_cpu_get_rate,
+};
+
 static DEFINE_CLK(gpio27, &clk_gpio27_ops);
 
+static DEFINE_CLK(cpu, &clk_cpu_ops);
+
 static struct clk_lookup sa11xx_clkregs[] = {
 	CLKDEV_INIT("sa1111.0", NULL, &clk_gpio27),
 	CLKDEV_INIT("sa1100-rtc", NULL, NULL),
+	CLKDEV_INIT("sa11x0-fb", NULL, &clk_cpu),
+	CLKDEV_INIT("sa11x0-pcmcia", NULL, &clk_cpu),
 };
 
 static int __init sa11xx_clk_init(void)
-- 
2.1.1

[PATCH 2/5] arm: sa1100: add a clock alias for sa1111 pcmcia device

[Dmitry Eremin-Solenikov]

SA-1111 uses internal MMIO space offsets as a device name, so device
name for sa1111 pcmcia is 1800 (PCMCIA is at offset 0x1800).

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 arch/arm/mach-sa1100/clock.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
index 53f750d..03c75a8 100644
--- a/arch/arm/mach-sa1100/clock.c
+++ b/arch/arm/mach-sa1100/clock.c
@@ -124,6 +124,8 @@ static struct clk_lookup sa11xx_clkregs[] = {
 	CLKDEV_INIT("sa1100-rtc", NULL, NULL),
 	CLKDEV_INIT("sa11x0-fb", NULL, &clk_cpu),
 	CLKDEV_INIT("sa11x0-pcmcia", NULL, &clk_cpu),
+	/* sa1111 names devices using internal offsets, PCMCIA is at 0x1800 */
+	CLKDEV_INIT("1800", NULL, &clk_cpu),
 };
 
 static int __init sa11xx_clk_init(void)
-- 
2.1.1

[PATCH 3/5] fbdev: sa1100fb: make use of device clock

[Dmitry Eremin-Solenikov]

Use per-device clock (instead of calling cpufreq_get(0), which can
return 0 if no cpu frequency driver is selected) to program timings.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/video/fbdev/sa1100fb.c | 24 +++++++++++++++++-------
 drivers/video/fbdev/sa1100fb.h |  1 +
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/video/fbdev/sa1100fb.c b/drivers/video/fbdev/sa1100fb.c
index 580c444e..8933840 100644
--- a/drivers/video/fbdev/sa1100fb.c
+++ b/drivers/video/fbdev/sa1100fb.c
@@ -178,6 +178,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/mutex.h>
 #include <linux/io.h>
+#include <linux/clk.h>
 
 #include <video/sa1100fb.h>
 
@@ -413,9 +414,9 @@ sa1100fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 		var->transp.offset);
 
 #ifdef CONFIG_CPU_FREQ
-	dev_dbg(fbi->dev, "dma period = %d ps, clock = %d kHz\n",
+	dev_dbg(fbi->dev, "dma period = %d ps, clock = %ld kHz\n",
 		sa1100fb_display_dma_period(var),
-		cpufreq_get(smp_processor_id()));
+		clk_get_rate(fbi->clk) / 1000);
 #endif
 
 	return 0;
@@ -586,9 +587,10 @@ static struct fb_ops sa1100fb_ops = {
  * Calculate the PCD value from the clock rate (in picoseconds).
  * We take account of the PPCR clock setting.
  */
-static inline unsigned int get_pcd(unsigned int pixclock, unsigned int cpuclock)
+static inline unsigned int get_pcd(struct sa1100fb_info *fbi,
+		unsigned int pixclock)
 {
-	unsigned int pcd = cpuclock / 100;
+	unsigned int pcd = clk_get_rate(fbi->clk) / 100 / 1000;
 
 	pcd *= pixclock;
 	pcd /= 10000000;
@@ -667,7 +669,7 @@ static int sa1100fb_activate_var(struct fb_var_screeninfo *var, struct sa1100fb_
 		LCCR2_BegFrmDel(var->upper_margin) +
 		LCCR2_EndFrmDel(var->lower_margin);
 
-	pcd = get_pcd(var->pixclock, cpufreq_get(0));
+	pcd = get_pcd(fbi, var->pixclock);
 	new_regs.lccr3 = LCCR3_PixClkDiv(pcd) | fbi->inf->lccr3 |
 		(var->sync & FB_SYNC_HOR_HIGH_ACT ? LCCR3_HorSnchH : LCCR3_HorSnchL) |
 		(var->sync & FB_SYNC_VERT_HIGH_ACT ? LCCR3_VrtSnchH : LCCR3_VrtSnchL);
@@ -1003,7 +1005,6 @@ sa1100fb_freq_transition(struct notifier_block *nb, unsigned long val,
 			 void *data)
 {
 	struct sa1100fb_info *fbi = TO_INF(nb, freq_transition);
-	struct cpufreq_freqs *f = data;
 	u_int pcd;
 
 	switch (val) {
@@ -1012,7 +1013,7 @@ sa1100fb_freq_transition(struct notifier_block *nb, unsigned long val,
 		break;
 
 	case CPUFREQ_POSTCHANGE:
-		pcd = get_pcd(fbi->fb.var.pixclock, f->new);
+		pcd = get_pcd(fbi, fbi->fb.var.pixclock);
 		fbi->reg_lccr3 = (fbi->reg_lccr3 & ~0xff) | LCCR3_PixClkDiv(pcd);
 		set_ctrlr_state(fbi, C_ENABLE_CLKCHANGE);
 		break;
@@ -1219,6 +1220,13 @@ static int sa1100fb_probe(struct platform_device *pdev)
 	if (!fbi)
 		goto failed;
 
+	fbi->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(fbi->clk)) {
+		ret = PTR_ERR(fbi->clk);
+		fbi->clk = NULL;
+		goto failed;
+	}
+
 	fbi->base = ioremap(res->start, resource_size(res));
 	if (!fbi->base)
 		goto failed;
@@ -1271,6 +1279,8 @@ static int sa1100fb_probe(struct platform_device *pdev)
  failed:
 	if (fbi)
 		iounmap(fbi->base);
+	if (fbi->clk)
+		clk_put(fbi->clk);
 	kfree(fbi);
 	release_mem_region(res->start, resource_size(res));
 	return ret;
diff --git a/drivers/video/fbdev/sa1100fb.h b/drivers/video/fbdev/sa1100fb.h
index fc5d429..0139d13 100644
--- a/drivers/video/fbdev/sa1100fb.h
+++ b/drivers/video/fbdev/sa1100fb.h
@@ -68,6 +68,7 @@ struct sa1100fb_info {
 #endif
 
 	const struct sa1100fb_mach_info *inf;
+	struct clk *clk;
 };
 
 #define TO_INF(ptr,member)	container_of(ptr,struct sa1100fb_info,member)
-- 
2.1.1

[PATCH 3/5] fbdev: sa1100fb: make use of device clock

[Tomi Valkeinen]

On 24/10/14 13:37, Dmitry Eremin-Solenikov wrote:
> Use per-device clock (instead of calling cpufreq_get(0), which can
> return 0 if no cpu frequency driver is selected) to program timings.
> 
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
>  drivers/video/fbdev/sa1100fb.c | 24 +++++++++++++++++-------
>  drivers/video/fbdev/sa1100fb.h |  1 +
>  2 files changed, 18 insertions(+), 7 deletions(-)

I presume this has to be merged with the rest of the patches, so:

Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

 Tomi


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20141028/2606d54c/attachment.sig>

[PATCH 4/5] pcmcia: sa1100: make use of device clock

[Dmitry Eremin-Solenikov]

Use per-device clock (instead of calling cpufreq_get(0), which can
return 0 if no cpu frequency driver is selected) to program timings.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/pcmcia/sa1100_generic.c |  1 +
 drivers/pcmcia/sa11xx_base.c    | 14 ++++++++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/pcmcia/sa1100_generic.c b/drivers/pcmcia/sa1100_generic.c
index ff8a027..d2ab060 100644
--- a/drivers/pcmcia/sa1100_generic.c
+++ b/drivers/pcmcia/sa1100_generic.c
@@ -93,6 +93,7 @@ static int sa11x0_drv_pcmcia_remove(struct platform_device *dev)
 	for (i = 0; i < sinfo->nskt; i++)
 		soc_pcmcia_remove_one(&sinfo->skt[i]);
 
+	clk_put(sinfo->clk);
 	kfree(sinfo);
 	return 0;
 }
diff --git a/drivers/pcmcia/sa11xx_base.c b/drivers/pcmcia/sa11xx_base.c
index 54d3089..6dd94bb 100644
--- a/drivers/pcmcia/sa11xx_base.c
+++ b/drivers/pcmcia/sa11xx_base.c
@@ -135,14 +135,16 @@ sa1100_pcmcia_frequency_change(struct soc_pcmcia_socket *skt,
 static int
 sa1100_pcmcia_set_timing(struct soc_pcmcia_socket *skt)
 {
-	return sa1100_pcmcia_set_mecr(skt, cpufreq_get(0));
+	unsigned long clk = clk_get_rate(skt->clk);
+
+	return sa1100_pcmcia_set_mecr(skt, clk / 1000);
 }
 
 static int
 sa1100_pcmcia_show_timing(struct soc_pcmcia_socket *skt, char *buf)
 {
 	struct soc_pcmcia_timing timing;
-	unsigned int clock = cpufreq_get(0);
+	unsigned int clock = clk_get_rate(skt->clk);
 	unsigned long mecr = MECR;
 	char *p = buf;
 
@@ -218,6 +220,11 @@ int sa11xx_drv_pcmcia_probe(struct device *dev, struct pcmcia_low_level *ops,
 	struct skt_dev_info *sinfo;
 	struct soc_pcmcia_socket *skt;
 	int i, ret = 0;
+	struct clk *clk;
+
+	clk = clk_get(dev, NULL);
+	if (IS_ERR(clk))
+		return -ENODEV;
 
 	sa11xx_drv_pcmcia_ops(ops);
 
@@ -226,12 +233,14 @@ int sa11xx_drv_pcmcia_probe(struct device *dev, struct pcmcia_low_level *ops,
 		return -ENOMEM;
 
 	sinfo->nskt = nr;
+	sinfo->clk = clk;
 
 	/* Initialize processor specific parameters */
 	for (i = 0; i < nr; i++) {
 		skt = &sinfo->skt[i];
 
 		skt->nr = first + i;
+		skt->clk = clk;
 		soc_pcmcia_init_one(skt, ops, dev);
 
 		ret = sa11xx_drv_pcmcia_add_one(skt);
@@ -242,6 +251,7 @@ int sa11xx_drv_pcmcia_probe(struct device *dev, struct pcmcia_low_level *ops,
 	if (ret) {
 		while (--i >= 0)
 			soc_pcmcia_remove_one(&sinfo->skt[i]);
+		clk_put(clk);
 		kfree(sinfo);
 	} else {
 		dev_set_drvdata(dev, sinfo);
-- 
2.1.1

[PATCH 5/5] pcmcia: sa1111: provide device clock

[Dmitry Eremin-Solenikov]

Both pxa2xx (long ago) and sa1100 (now) make use of clock device to get
the cpu speed. Make sa1111 glue code provide clock to platform layer.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/pcmcia/sa1111_generic.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/pcmcia/sa1111_generic.c b/drivers/pcmcia/sa1111_generic.c
index 65b02c3..c5988be 100644
--- a/drivers/pcmcia/sa1111_generic.c
+++ b/drivers/pcmcia/sa1111_generic.c
@@ -145,6 +145,9 @@ int sa1111_pcmcia_add(struct sa1111_dev *dev, struct pcmcia_low_level *ops,
 			return -ENOMEM;
 
 		s->soc.nr = ops->first + i;
+		s->soc.clk = clk_get(&dev->dev, NULL);
+		if (IS_ERR(s->soc.clk))
+			return -ENODEV;
 		soc_pcmcia_init_one(&s->soc, ops, &dev->dev);
 		s->dev = dev;
 		if (s->soc.nr) {
@@ -220,6 +223,7 @@ static int pcmcia_remove(struct sa1111_dev *dev)
 	for (; s; s = next) {
 		next = s->next;
 		soc_pcmcia_remove_one(&s->soc);
+		clk_put(s->soc.clk);
 		kfree(s);
 	}
 
-- 
2.1.1

[PATCH 0/5] arm: sa1100: fix sa1100 fb and pcmcia w/o cpufreq

[Dmitry Eremin-Solenikov]

2014-10-24 13:37 GMT+03:00 Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>:
> Hello,
>
> These patches were sitting in my queue for some time. On SA-1100
> framebuffer and PCMCIA drivers make use of cpufreq_get(0) function call
> to determine the cpu frequency. Russell's commit
> 1937f5b91833e2e8e53bcc821fc7a5fbe6ccb9b5 (ARM: fix sa1100 build) fixed
> the build issues, but broke two devices (Collie and Jornada720). For
> those two boards the cpufreq code gets compiled but is not enabled (as
> board files do not provide timing information for the CPUFREQ driver).
> Thus cpufreq_get(0) returns incorrect values and incorrect timings get
> programmed into the hardware.
>
> PXA2xx (the very similar platform) uses Clock API to determine CPU
> frequency both in framebuffer and PCMCIA drivers. These patches make
> similar changes to StrongARM drivers.
>
> These patches are required to make use of framebuffer and CF card on
> Sharp Collie (and possibly on HP Jornada 720).

Russell, what about these patches?
They are absolutely required for Collie to work properly.


-- 
With best wishes
Dmitry