Re: [PATCHv11 43/49] ARM: OMAP2+: PRM: add support for initializing PRCM clock modules from DT

[Tero Kristo <t-kristo@ti.com>]

On 12/20/2013 01:49 PM, Paul Walmsley wrote:
> On Thu, 19 Dec 2013, Tero Kristo wrote:
>
>> This patch provides top level functionality for the DT clock initialization.
>> Clock tree is initialized hierarchically starting from IP modules (CM/PRM/PRCM)
>> going down towards individual clock nodes, and finally initializing
>> clockdomains once all the clocks are ready.
>
> So just to flag this as something we'll want to deal with later.
> The low-level CM* drivers should be responsible for registering CM* clocks
> and clockdomains.  Similarly the PRM* low-level drivers should only
> register PRM* clocks and clockdomains.  But it looks to me like we can
> rearrange this code later without any significant impact, unless you
> foresee any issues with that?  If not, in the interests of expediency,
> let's take that up in future patches.

Yeah, this can be split under cm/prm later on once we implement proper 
drivers for each block. DT data won't be changed, just kernel side 
implementation will be modified, and this modification is relatively 
simple to do also.

-Tero

>
>
> - Paul
>
>>
>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>> ---
>>   arch/arm/mach-omap2/prm.h        |    1 +
>>   arch/arm/mach-omap2/prm_common.c |   66 ++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 67 insertions(+)
>>
>> diff --git a/arch/arm/mach-omap2/prm.h b/arch/arm/mach-omap2/prm.h
>> index ac25ae6..623db40 100644
>> --- a/arch/arm/mach-omap2/prm.h
>> +++ b/arch/arm/mach-omap2/prm.h
>> @@ -18,6 +18,7 @@
>>   # ifndef __ASSEMBLER__
>>   extern void __iomem *prm_base;
>>   extern void omap2_set_globals_prm(void __iomem *prm);
>> +int of_prcm_init(void);
>>   # endif
>>
>>
>> diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c
>> index a2e1174..835eb7d 100644
>> --- a/arch/arm/mach-omap2/prm_common.c
>> +++ b/arch/arm/mach-omap2/prm_common.c
>> @@ -23,6 +23,10 @@
>>   #include <linux/irq.h>
>>   #include <linux/interrupt.h>
>>   #include <linux/slab.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/clk-provider.h>
>> +#include <linux/clk/ti.h>
>>
>>   #include "soc.h"
>>   #include "prm2xxx_3xxx.h"
>> @@ -30,6 +34,7 @@
>>   #include "prm3xxx.h"
>>   #include "prm44xx.h"
>>   #include "common.h"
>> +#include "clock.h"
>>
>>   /*
>>    * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
>> @@ -464,3 +469,64 @@ int prm_unregister(struct prm_ll_data *pld)
>>
>>   	return 0;
>>   }
>> +
>> +static struct of_device_id omap_prcm_dt_match_table[] = {
>> +	{ .compatible = "ti,am3-prcm" },
>> +	{ .compatible = "ti,am3-scrm" },
>> +	{ .compatible = "ti,am4-prcm" },
>> +	{ .compatible = "ti,am4-scrm" },
>> +	{ .compatible = "ti,omap3-prm" },
>> +	{ .compatible = "ti,omap3-cm" },
>> +	{ .compatible = "ti,omap3-scrm" },
>> +	{ .compatible = "ti,omap4-cm1" },
>> +	{ .compatible = "ti,omap4-prm" },
>> +	{ .compatible = "ti,omap4-cm2" },
>> +	{ .compatible = "ti,omap4-scrm" },
>> +	{ .compatible = "ti,omap5-prm" },
>> +	{ .compatible = "ti,omap5-cm-core-aon" },
>> +	{ .compatible = "ti,omap5-scrm" },
>> +	{ .compatible = "ti,omap5-cm-core" },
>> +	{ .compatible = "ti,dra7-prm" },
>> +	{ .compatible = "ti,dra7-cm-core-aon" },
>> +	{ .compatible = "ti,dra7-cm-core" },
>> +	{ }
>> +};
>> +
>> +static struct clk_hw_omap memmap_dummy_ck = {
>> +	.flags = MEMMAP_ADDRESSING,
>> +};
>> +
>> +static u32 prm_clk_readl(u32 *reg)
>> +{
>> +	return omap2_clk_readl(&memmap_dummy_ck, reg);
>> +}
>> +
>> +static void prm_clk_writel(u32 val, u32 *reg)
>> +{
>> +	omap2_clk_writel(val, &memmap_dummy_ck, reg);
>> +}
>> +
>> +static struct clk_ll_ops omap_clk_ll_ops = {
>> +	.clk_readl = prm_clk_readl,
>> +	.clk_writel = prm_clk_writel,
>> +};
>> +
>> +int __init of_prcm_init(void)
>> +{
>> +	struct device_node *np;
>> +	void __iomem *mem;
>> +	int memmap_index = 0;
>> +
>> +	ti_clk_ll_ops = &omap_clk_ll_ops;
>> +
>> +	for_each_matching_node(np, omap_prcm_dt_match_table) {
>> +		mem = of_iomap(np, 0);
>> +		clk_memmaps[memmap_index] = mem;
>> +		ti_dt_clk_init_provider(np, memmap_index);
>> +		memmap_index++;
>> +	}
>> +
>> +	ti_dt_clockdomains_setup();
>> +
>> +	return 0;
>> +}
>> --
>> 1.7.9.5
>>
>
>
> - Paul
>