Re: [PATCH v7 16/21] memory: mtk-smi: Add bus_sel for mt8183

From: Matthias Brugger
Date: Tue Jun 18 2019 - 17:12:43 EST




On 18/06/2019 14:10, Yong Wu wrote:
> On Mon, 2019-06-17 at 18:23 +0200, Matthias Brugger wrote:
>>
>> On 10/06/2019 14:17, Yong Wu wrote:
>>> There are 2 mmu cells in a M4U HW. we could adjust some larbs entering
>>> mmu0 or mmu1 to balance the bandwidth via the smi-common register
>>> SMI_BUS_SEL(0x220)(Each larb occupy 2 bits).
>>>
>>> In mt8183, For better performance, we switch larb1/2/5/7 to enter
>>> mmu1 while the others still keep enter mmu0.
>>>
>>> In mt8173 and mt2712, we don't get the performance issue,
>>> Keep its default value(0x0), that means all the larbs enter mmu0.
>>>
>>> Note: smi gen1(mt2701/mt7623) don't have this bus_sel.
>>>
>>> And, the base of smi-common is completely different with smi_ao_base
>>> of gen1, thus I add new variable for that.
>>>
>>> CC: Matthias Brugger <matthias.bgg@xxxxxxxxx>
>>> Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
>>> Reviewed-by: Evan Green <evgreen@xxxxxxxxxxxx>
>>> ---
>>> drivers/memory/mtk-smi.c | 22 ++++++++++++++++++++--
>>> 1 file changed, 20 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
>>> index 9790801..08cf40d 100644
>>> --- a/drivers/memory/mtk-smi.c
>>> +++ b/drivers/memory/mtk-smi.c
>>> @@ -49,6 +49,12 @@
>>> #define SMI_LARB_NONSEC_CON(id) (0x380 + ((id) * 4))
>>> #define F_MMU_EN BIT(0)
>>>
>>> +/* SMI COMMON */
>>> +#define SMI_BUS_SEL 0x220
>>> +#define SMI_BUS_LARB_SHIFT(larbid) ((larbid) << 1)
>>> +/* All are MMU0 defaultly. Only specialize mmu1 here. */
>>> +#define F_MMU1_LARB(larbid) (0x1 << SMI_BUS_LARB_SHIFT(larbid))
>>> +
>>> enum mtk_smi_gen {
>>> MTK_SMI_GEN1,
>>> MTK_SMI_GEN2
>>> @@ -57,6 +63,7 @@ enum mtk_smi_gen {
>>> struct mtk_smi_common_plat {
>>> enum mtk_smi_gen gen;
>>> bool has_gals;
>>> + u32 bus_sel; /* Balance some larbs to enter mmu0 or mmu1 */
>>> };
>>>
>>> struct mtk_smi_larb_gen {
>>> @@ -72,8 +79,8 @@ struct mtk_smi {
>>> struct clk *clk_apb, *clk_smi;
>>> struct clk *clk_gals0, *clk_gals1;
>>> struct clk *clk_async; /*only needed by mt2701*/
>>> - void __iomem *smi_ao_base;
>>> -
>>> + void __iomem *smi_ao_base; /* only for gen1 */
>>> + void __iomem *base; /* only for gen2 */
>>
>> union {} maybe?
>
> Yes. Thanks.
>
> I will add it.
>
>>
>>> const struct mtk_smi_common_plat *plat;
>>> };
>>>
>>> @@ -410,6 +417,8 @@ static int __maybe_unused mtk_smi_larb_suspend(struct device *dev)
>>> static const struct mtk_smi_common_plat mtk_smi_common_mt8183 = {
>>> .gen = MTK_SMI_GEN2,
>>> .has_gals = true,
>>> + .bus_sel = F_MMU1_LARB(1) | F_MMU1_LARB(2) | F_MMU1_LARB(5) |
>>> + F_MMU1_LARB(7),
>>> };
>>>
>>> static const struct of_device_id mtk_smi_common_of_ids[] = {
>>> @@ -482,6 +491,11 @@ static int mtk_smi_common_probe(struct platform_device *pdev)
>>> ret = clk_prepare_enable(common->clk_async);
>>> if (ret)
>>> return ret;
>>> + } else {
>>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>> + common->base = devm_ioremap_resource(dev, res);
>>> + if (IS_ERR(common->base))
>>> + return PTR_ERR(common->base);
>>
>> We must be backwards compatible with DT which does not have the base defined.
>
> The smi-common node in the previous mt2712 and mt8173 also have the
> "reg" property even though they didn't use this base, Thus, It looks ok
> for all the cases.
>

Correct, it is defined as a required property in the binding description so we
are good.
Sorry for the noise.

With the union added you can add:
Reviewed-by: Matthias Brugger <matthias.bgg@xxxxxxxxx>

>>
>> Regards,
>> Matthias
>>
>>> }
>>> pm_runtime_enable(dev);
>>> platform_set_drvdata(pdev, common);
>>> @@ -497,6 +511,7 @@ static int mtk_smi_common_remove(struct platform_device *pdev)
>>> static int __maybe_unused mtk_smi_common_resume(struct device *dev)
>>> {
>>> struct mtk_smi *common = dev_get_drvdata(dev);
>>> + u32 bus_sel = common->plat->bus_sel;
>>> int ret;
>>>
>>> ret = mtk_smi_clk_enable(common);
>>> @@ -504,6 +519,9 @@ static int __maybe_unused mtk_smi_common_resume(struct device *dev)
>>> dev_err(common->dev, "Failed to enable clock(%d).\n", ret);
>>> return ret;
>>> }
>>> +
>>> + if (common->plat->gen == MTK_SMI_GEN2 && bus_sel)
>>> + writel(bus_sel, common->base + SMI_BUS_SEL);
>>> return 0;
>>> }
>>>
>>>
>
>