Re: [PATCH 3/6] msm8994 clocks: global clock support for msm8994 SOC.

[Jeremy McNicoll <jmcnicol@redhat.com>]

On Thu, Oct 27, 2016 at 05:18:00PM -0700, Stephen Boyd wrote:
> On 10/25, Jeremy McNicoll wrote:
> > diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
> > index 0146d3c..3b78803 100644
> > --- a/drivers/clk/qcom/Kconfig
> > +++ b/drivers/clk/qcom/Kconfig
> > @@ -132,6 +132,15 @@ config MSM_MMCC_8974
> >  	  Say Y if you want to support multimedia devices such as display,
> >  	  graphics, video encode/decode, camera, etc.
> >  
> > +config MSM_GCC_8994
> > +	tristate "MSM8994 Global Clock Controller"
> > +	select QCOM_GDSC
> 
> But we aren't populating GDSCs so this is unnecessary right now.
> 
> > +	depends on COMMON_CLK_QCOM
> > +	help
> > +	  Support for the global clock controller on msm8994 devices.
> > +	  Say Y if you want to use peripheral devices such as UART, SPI,
> > +	  i2c, USB, SD/eMMC, SATA, PCIe, etc.
> 
> Is there a sata controller on 8994? Is there an emmc/sd
> controller?
>

According to this marketing slide. 

https://www.qualcomm.com/products/snapdragon/processors/810

We will strip down the list to something like:

....Say Y if you want to use peripheral devices such as UART, USB, etc..

BTW - the help message was identical to the msm8996 which is currently 
in tree.   Hopefully that help message is accurately describes the HW.

-jeremy


> > +
> >  config MSM_GCC_8996
> >  	tristate "MSM8996 Global Clock Controller"
> >  	select QCOM_GDSC
> > diff --git a/drivers/clk/qcom/gcc-msm8994.c b/drivers/clk/qcom/gcc-msm8994.c
> > new file mode 100644
> > index 0000000..39b40d4
> > --- /dev/null
> > +++ b/drivers/clk/qcom/gcc-msm8994.c
> > @@ -0,0 +1,2501 @@
> > +/* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 and
> > + * only version 2 as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/init.h>
> > +#include <linux/err.h>
> > +#include <linux/ctype.h>
> > +#include <linux/io.h>
> > +#include <linux/clk.h>
> 
> Is this include used? Should probably be clk-provider instead.
> 
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +
> > +#include <dt-bindings/clock/qcom,gcc-msm8994.h>
> > +
> > +#include "common.h"
> > +#include "clk-regmap.h"
> > +#include "clk-pll.h"
> 
> Is this include used?
> 
> > +#include "clk-alpha-pll.h"
> > +#include "clk-rcg.h"
> > +#include "clk-branch.h"
> > +#include "reset.h"
> > +
> > +static struct clk_branch gcc_usb30_mock_utmi_clk = {
> > +	.halt_reg = 0x03D0,
> 
> Lowercase hex everywhere please.
> 
> > +
> > +
> > +static void msm_gcc_8994v2_fixup(void)
> > +{
> > +	ufs_axi_clk_src.freq_tbl = ftbl_ufs_axi_clk_src_v2;
> > +
> > +	blsp1_qup1_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp1_qup2_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp1_qup3_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp1_qup4_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp1_qup5_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp1_qup6_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup1_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup2_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup3_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup4_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup5_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> > +	blsp2_qup6_spi_apps_clk_src.freq_tbl = ftbl_blspqup_spi_apps_clk_src_v2;
> 
> Please no, just assume v2.
> 
> > +}
> > +
> > +static const struct regmap_config gcc_msm8994_regmap_config = {
> > +	.reg_bits	= 32,
> > +	.reg_stride	= 4,
> > +	.val_bits	= 32,
> > +	.max_register	= 0x2000,
> > +	.fast_io	= true,
> > +};
> > +
> > +static const struct qcom_cc_desc gcc_msm8994_desc = {
> > +	.config = &gcc_msm8994_regmap_config,
> > +	.clks = gcc_msm8994_clocks,
> > +	.num_clks = ARRAY_SIZE(gcc_msm8994_clocks),
> > +	.resets = NULL,
> > +	.num_resets = 0,
> > +	.gdscs = NULL,
> > +	.num_gdscs = 0,
> 
> We don't have to be explicit. Does this even work? I thought
> common.c expected there to be a reset list? I guess we would have
> a reset controller with no resets. Should be possible to grab
> some of the resets out of the android driver though.
> 
> > +};
> > +
> > +static const struct of_device_id gcc_msm8994_match_table[] = {
> > +	{ .compatible = "qcom,gcc-8994" },
> > +	{ .compatible = "qcom,gcc-8994v2" },
> 
> Please add msm and drop the v2 one.
> 
> > +	{}
> > +}
> > +
> > +MODULE_DEVICE_TABLE(of, gcc_msm8994_match_table);
> > +
> > +static int gcc_msm8994_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	struct clk *clk;
> > +	const char *compat = NULL;
> > +	int compatlen = 0;
> > +	bool is_v2 = false;
> > +
> > +	clk = devm_clk_register(dev, &xo.hw);
> > +	if (IS_ERR(clk))
> > +		return PTR_ERR(clk);
> > +
> > +	compat = of_get_property(pdev->dev.of_node, "compatible", &compatlen);
> > +	if (!compat || (compatlen <= 0))
> > +		return -EINVAL;
> > +
> > +	is_v2 = !strcmp(compat, "qcom,gcc-8994v2");
> > +	if (is_v2)
> > +		msm_gcc_8994v2_fixup();
> 
> This should simplify greatly.
> 
> > +
> > +	return qcom_cc_probe(pdev, &gcc_msm8994_desc);
> > +}
> 
> -- 
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