On Thu, 2022-09-08 at 14:58 -0600, Mathieu Poirier wrote:
> On Thu, 8 Sept 2022 at 05:21, Tinghan Shen <[email protected]>
> wrote:
>
> > Hi Mathieu,
> >
> > > > The mtk_scp.c driver only supports the single core SCP and the
> > > > 1st core of a dual-core SCP. This patch extends it for the 2nd core.
> > > >
> > > > MT8195 SCP is a dual-core MCU. Both cores are housed in the same
> >
> > subsys.
> > >
> > > s/subsys/subsystem
> > >
> > > > They have the same viewpoint of registers and memory.
> > > >
> > > > Core 1 of the SCP features its own set of core configuration registers,
> > > > interrupt controller, timers, and DMAs. The rest of the peripherals
> > > > in this subsystem are shared by core 0 and core 1.
> > > >
> > > > As for memory, core 1 has its own cache memory. the SCP SRAM is shared
> > >
> > > /the/The
> > >
> > > > by core 0 and core 1.
> > > >
> > > > Signed-off-by: Tinghan Shen <[email protected]>
> > > > ---
> > > > drivers/remoteproc/mtk_scp.c | 22 ++++++++++++++++++++--
> > > > 1 file changed, 20 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/remoteproc/mtk_scp.c
> >
> > b/drivers/remoteproc/mtk_scp.c
> > > > index 3510c6d0bbc8..91b4aefde4ac 100644
> > > > --- a/drivers/remoteproc/mtk_scp.c
> > > > +++ b/drivers/remoteproc/mtk_scp.c
> > > > @@ -23,6 +23,10 @@
> > > > #define MAX_CODE_SIZE 0x500000
> > > > #define SECTION_NAME_IPI_BUFFER ".ipi_buffer"
> > > >
> > > > +#define SCP_CORE_0 0
> > > > +#define SCP_CORE_1 1
> > > > +#define SCP_CORE_SINGLE 0xF
> > > > +
> > > > /**
> > > > * scp_get() - get a reference to SCP.
> > > > *
> > > > @@ -836,6 +840,7 @@ static int scp_probe(struct platform_device *pdev)
> > > > struct resource *res;
> > > > const char *fw_name = "scp.img";
> > > > int ret, i;
> > > > + u32 core_id = SCP_CORE_SINGLE;
> > > >
> > > > ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > > > if (ret < 0 && ret != -EINVAL)
> > > > @@ -851,8 +856,16 @@ static int scp_probe(struct platform_device *pdev)
> > > > scp->data = of_device_get_match_data(dev);
> > > > platform_set_drvdata(pdev, scp);
> > > >
> > > > + ret = of_property_read_u32_index(dev->of_node,
> >
> > "mediatek,scp-core", 1, &core_id);
> > > > + if (ret == 0)
> > > > + dev_info(dev, "Boot SCP dual core %u\n", core_id);
> > >
> > > Why is the DT property "mediatek,scp-core" needed at all? Since the
> >
> > compatible
> > > "mediatek,mt8195-scp-dual" has already been defined previously in this
> >
> > patchset,
> > > initialising the second core, if present, is a matter of looking at the
> > > compatile string.
> >
> > This idea of identify cores by the compatible looks workable.
> > I'll update this series at next version.
> > Thanks!
> >
> > >
> > > > +
> > > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
> > > > - scp->sram_base = devm_ioremap_resource(dev, res);
> > > > + if (core_id == SCP_CORE_1)
> > > > + scp->sram_base = devm_ioremap(dev, res->start,
> >
> > resource_size(res));
> > > > + else
> > > > + scp->sram_base = devm_ioremap_resource(dev, res);
> > > > +
> > >
> > > This looks very broken... For this to work you would need to have two DT
> > > entries with the "mediatek,mt8195-scp-dual" compatible properly, one with
> > > "mediatek,scp-core = <&scp_dual1 0>;" and another one with
> >
> > "mediatek,scp-core = <&scp_dual0 1>;".
> > >
> > > Which is also very broken... Here you have a binding whose first
> >
> > argument is a
> > > reference to the core sibling while the second argument is a
> >
> > characteristic of
> > > the current core, which is highly confusing.
> > >
> > > I suggest what when you see the compatible binding
> >
> > "mediatek,mt8195-scp", a
> > > single core is initialized. If you see "mediatek,mt8195-scp-dual", both
> >
> > cores
> > > are initialized as part of the _same_ probe.
> > >
> > > If the above analysis is not correct it means I misinterpreted your
> > > work and if so, a serious amount of comments is needed _and_ a very
> >
> > detailed
> > > example in "mtk,scp.yaml" that leaves no room for interpretation.
> > >
> > > I will stop reviewing this patchset until you have clarified how this
> >
> > works.
> > >
> > > Thanks,
> > > Mathieu
> >
> > There's one problem of initializng the CORE1 using the same probe flow.
> > The register space of CORE0 and CORE1 are overlapped in the device node.
> > Both cores need to use the 'cfg' registers defined in scp yaml.
> > The devm_ioremap_resource catches address overlapping and returns error
> > when
> > probing CORE1 driver.
> >
>
> That is exactly why I suggest to initialise both cores within the same
> probe() function.
>
Hi Mathieu,
I'm thinking about how to initialise in the same probe() function.
I'm wondering if this implies that using one scp driver to initialize 2 cores?
If it is, I assume the dts descriptions for both cores should be contained in one node.
When there's one node for both cores, it looks like that there is a problem of
using dma_allocate_coherent(). Each core has its own reserved memory region.
When there's only one device for both cores, it's not able to identify the memory region
by the device parameter of dma_allocate_coherent().
Is it acceptable to consider manually allocating core 1 device in the probe() when probing core 0?
Best regards,
TingHan
On Fri, 16 Sept 2022 at 06:00, TingHan Shen <[email protected]> wrote:
>
> On Thu, 2022-09-08 at 14:58 -0600, Mathieu Poirier wrote:
> > On Thu, 8 Sept 2022 at 05:21, Tinghan Shen <[email protected]>
> > wrote:
> >
> > > Hi Mathieu,
> > >
> > > > > The mtk_scp.c driver only supports the single core SCP and the
> > > > > 1st core of a dual-core SCP. This patch extends it for the 2nd core.
> > > > >
> > > > > MT8195 SCP is a dual-core MCU. Both cores are housed in the same
> > >
> > > subsys.
> > > >
> > > > s/subsys/subsystem
> > > >
> > > > > They have the same viewpoint of registers and memory.
> > > > >
> > > > > Core 1 of the SCP features its own set of core configuration registers,
> > > > > interrupt controller, timers, and DMAs. The rest of the peripherals
> > > > > in this subsystem are shared by core 0 and core 1.
> > > > >
> > > > > As for memory, core 1 has its own cache memory. the SCP SRAM is shared
> > > >
> > > > /the/The
> > > >
> > > > > by core 0 and core 1.
> > > > >
> > > > > Signed-off-by: Tinghan Shen <[email protected]>
> > > > > ---
> > > > > drivers/remoteproc/mtk_scp.c | 22 ++++++++++++++++++++--
> > > > > 1 file changed, 20 insertions(+), 2 deletions(-)
> > > > >
> > > > > diff --git a/drivers/remoteproc/mtk_scp.c
> > >
> > > b/drivers/remoteproc/mtk_scp.c
> > > > > index 3510c6d0bbc8..91b4aefde4ac 100644
> > > > > --- a/drivers/remoteproc/mtk_scp.c
> > > > > +++ b/drivers/remoteproc/mtk_scp.c
> > > > > @@ -23,6 +23,10 @@
> > > > > #define MAX_CODE_SIZE 0x500000
> > > > > #define SECTION_NAME_IPI_BUFFER ".ipi_buffer"
> > > > >
> > > > > +#define SCP_CORE_0 0
> > > > > +#define SCP_CORE_1 1
> > > > > +#define SCP_CORE_SINGLE 0xF
> > > > > +
> > > > > /**
> > > > > * scp_get() - get a reference to SCP.
> > > > > *
> > > > > @@ -836,6 +840,7 @@ static int scp_probe(struct platform_device *pdev)
> > > > > struct resource *res;
> > > > > const char *fw_name = "scp.img";
> > > > > int ret, i;
> > > > > + u32 core_id = SCP_CORE_SINGLE;
> > > > >
> > > > > ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > > > > if (ret < 0 && ret != -EINVAL)
> > > > > @@ -851,8 +856,16 @@ static int scp_probe(struct platform_device *pdev)
> > > > > scp->data = of_device_get_match_data(dev);
> > > > > platform_set_drvdata(pdev, scp);
> > > > >
> > > > > + ret = of_property_read_u32_index(dev->of_node,
> > >
> > > "mediatek,scp-core", 1, &core_id);
> > > > > + if (ret == 0)
> > > > > + dev_info(dev, "Boot SCP dual core %u\n", core_id);
> > > >
> > > > Why is the DT property "mediatek,scp-core" needed at all? Since the
> > >
> > > compatible
> > > > "mediatek,mt8195-scp-dual" has already been defined previously in this
> > >
> > > patchset,
> > > > initialising the second core, if present, is a matter of looking at the
> > > > compatile string.
> > >
> > > This idea of identify cores by the compatible looks workable.
> > > I'll update this series at next version.
> > > Thanks!
> > >
> > > >
> > > > > +
> > > > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
> > > > > - scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > + if (core_id == SCP_CORE_1)
> > > > > + scp->sram_base = devm_ioremap(dev, res->start,
> > >
> > > resource_size(res));
> > > > > + else
> > > > > + scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > +
> > > >
> > > > This looks very broken... For this to work you would need to have two DT
> > > > entries with the "mediatek,mt8195-scp-dual" compatible properly, one with
> > > > "mediatek,scp-core = <&scp_dual1 0>;" and another one with
> > >
> > > "mediatek,scp-core = <&scp_dual0 1>;".
> > > >
> > > > Which is also very broken... Here you have a binding whose first
> > >
> > > argument is a
> > > > reference to the core sibling while the second argument is a
> > >
> > > characteristic of
> > > > the current core, which is highly confusing.
> > > >
> > > > I suggest what when you see the compatible binding
> > >
> > > "mediatek,mt8195-scp", a
> > > > single core is initialized. If you see "mediatek,mt8195-scp-dual", both
> > >
> > > cores
> > > > are initialized as part of the _same_ probe.
> > > >
> > > > If the above analysis is not correct it means I misinterpreted your
> > > > work and if so, a serious amount of comments is needed _and_ a very
> > >
> > > detailed
> > > > example in "mtk,scp.yaml" that leaves no room for interpretation.
> > > >
> > > > I will stop reviewing this patchset until you have clarified how this
> > >
> > > works.
> > > >
> > > > Thanks,
> > > > Mathieu
> > >
> > > There's one problem of initializng the CORE1 using the same probe flow.
> > > The register space of CORE0 and CORE1 are overlapped in the device node.
> > > Both cores need to use the 'cfg' registers defined in scp yaml.
> > > The devm_ioremap_resource catches address overlapping and returns error
> > > when
> > > probing CORE1 driver.
> > >
> >
> > That is exactly why I suggest to initialise both cores within the same
> > probe() function.
> >
>
> Hi Mathieu,
>
> I'm thinking about how to initialise in the same probe() function.
> I'm wondering if this implies that using one scp driver to initialize 2 cores?
> If it is, I assume the dts descriptions for both cores should be contained in one node.
>
> When there's one node for both cores, it looks like that there is a problem of
> using dma_allocate_coherent(). Each core has its own reserved memory region.
> When there's only one device for both cores, it's not able to identify the memory region
> by the device parameter of dma_allocate_coherent().
>
> Is it acceptable to consider manually allocating core 1 device in the probe() when probing core 0?
Look at what Suman did for TI's K3 R5[1] and DSP[2] platforms.
Reviewing the bindings for both platforms will also give you a good
idea of how things work.
[1]. https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_r5_remoteproc.c#L1683
[2]. https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_dsp_remoteproc.c#L673
>
>
> Best regards,
> TingHan
>
>
>
>
>
>
>
>
On Fri, 2022-09-16 at 11:15 -0600, Mathieu Poirier wrote:
> On Fri, 16 Sept 2022 at 06:00, TingHan Shen <[email protected]> wrote:
> >
> > On Thu, 2022-09-08 at 14:58 -0600, Mathieu Poirier wrote:
> > > On Thu, 8 Sept 2022 at 05:21, Tinghan Shen <[email protected]>
> > > wrote:
> > >
> > > > Hi Mathieu,
> > > >
> > > > > > The mtk_scp.c driver only supports the single core SCP and the
> > > > > > 1st core of a dual-core SCP. This patch extends it for the 2nd core.
> > > > > >
> > > > > > MT8195 SCP is a dual-core MCU. Both cores are housed in the same
> > > >
> > > > subsys.
> > > > >
> > > > > s/subsys/subsystem
> > > > >
> > > > > > They have the same viewpoint of registers and memory.
> > > > > >
> > > > > > Core 1 of the SCP features its own set of core configuration registers,
> > > > > > interrupt controller, timers, and DMAs. The rest of the peripherals
> > > > > > in this subsystem are shared by core 0 and core 1.
> > > > > >
> > > > > > As for memory, core 1 has its own cache memory. the SCP SRAM is shared
> > > > >
> > > > > /the/The
> > > > >
> > > > > > by core 0 and core 1.
> > > > > >
> > > > > > Signed-off-by: Tinghan Shen <[email protected]>
> > > > > > ---
> > > > > > drivers/remoteproc/mtk_scp.c | 22 ++++++++++++++++++++--
> > > > > > 1 file changed, 20 insertions(+), 2 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/remoteproc/mtk_scp.c
> > > >
> > > > b/drivers/remoteproc/mtk_scp.c
> > > > > > index 3510c6d0bbc8..91b4aefde4ac 100644
> > > > > > --- a/drivers/remoteproc/mtk_scp.c
> > > > > > +++ b/drivers/remoteproc/mtk_scp.c
> > > > > > @@ -23,6 +23,10 @@
> > > > > > #define MAX_CODE_SIZE 0x500000
> > > > > > #define SECTION_NAME_IPI_BUFFER ".ipi_buffer"
> > > > > >
> > > > > > +#define SCP_CORE_0 0
> > > > > > +#define SCP_CORE_1 1
> > > > > > +#define SCP_CORE_SINGLE 0xF
> > > > > > +
> > > > > > /**
> > > > > > * scp_get() - get a reference to SCP.
> > > > > > *
> > > > > > @@ -836,6 +840,7 @@ static int scp_probe(struct platform_device *pdev)
> > > > > > struct resource *res;
> > > > > > const char *fw_name = "scp.img";
> > > > > > int ret, i;
> > > > > > + u32 core_id = SCP_CORE_SINGLE;
> > > > > >
> > > > > > ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > > > > > if (ret < 0 && ret != -EINVAL)
> > > > > > @@ -851,8 +856,16 @@ static int scp_probe(struct platform_device *pdev)
> > > > > > scp->data = of_device_get_match_data(dev);
> > > > > > platform_set_drvdata(pdev, scp);
> > > > > >
> > > > > > + ret = of_property_read_u32_index(dev->of_node,
> > > >
> > > > "mediatek,scp-core", 1, &core_id);
> > > > > > + if (ret == 0)
> > > > > > + dev_info(dev, "Boot SCP dual core %u\n", core_id);
> > > > >
> > > > > Why is the DT property "mediatek,scp-core" needed at all? Since the
> > > >
> > > > compatible
> > > > > "mediatek,mt8195-scp-dual" has already been defined previously in this
> > > >
> > > > patchset,
> > > > > initialising the second core, if present, is a matter of looking at the
> > > > > compatile string.
> > > >
> > > > This idea of identify cores by the compatible looks workable.
> > > > I'll update this series at next version.
> > > > Thanks!
> > > >
> > > > >
> > > > > > +
> > > > > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
> > > > > > - scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > > + if (core_id == SCP_CORE_1)
> > > > > > + scp->sram_base = devm_ioremap(dev, res->start,
> > > >
> > > > resource_size(res));
> > > > > > + else
> > > > > > + scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > > +
> > > > >
> > > > > This looks very broken... For this to work you would need to have two DT
> > > > > entries with the "mediatek,mt8195-scp-dual" compatible properly, one with
> > > > > "mediatek,scp-core = <&scp_dual1 0>;" and another one with
> > > >
> > > > "mediatek,scp-core = <&scp_dual0 1>;".
> > > > >
> > > > > Which is also very broken... Here you have a binding whose first
> > > >
> > > > argument is a
> > > > > reference to the core sibling while the second argument is a
> > > >
> > > > characteristic of
> > > > > the current core, which is highly confusing.
> > > > >
> > > > > I suggest what when you see the compatible binding
> > > >
> > > > "mediatek,mt8195-scp", a
> > > > > single core is initialized. If you see "mediatek,mt8195-scp-dual", both
> > > >
> > > > cores
> > > > > are initialized as part of the _same_ probe.
> > > > >
> > > > > If the above analysis is not correct it means I misinterpreted your
> > > > > work and if so, a serious amount of comments is needed _and_ a very
> > > >
> > > > detailed
> > > > > example in "mtk,scp.yaml" that leaves no room for interpretation.
> > > > >
> > > > > I will stop reviewing this patchset until you have clarified how this
> > > >
> > > > works.
> > > > >
> > > > > Thanks,
> > > > > Mathieu
> > > >
> > > > There's one problem of initializng the CORE1 using the same probe flow.
> > > > The register space of CORE0 and CORE1 are overlapped in the device node.
> > > > Both cores need to use the 'cfg' registers defined in scp yaml.
> > > > The devm_ioremap_resource catches address overlapping and returns error
> > > > when
> > > > probing CORE1 driver.
> > > >
> > >
> > > That is exactly why I suggest to initialise both cores within the same
> > > probe() function.
> > >
> >
> > Hi Mathieu,
> >
> > I'm thinking about how to initialise in the same probe() function.
> > I'm wondering if this implies that using one scp driver to initialize 2 cores?
> > If it is, I assume the dts descriptions for both cores should be contained in one node.
> >
> > When there's one node for both cores, it looks like that there is a problem of
> > using dma_allocate_coherent(). Each core has its own reserved memory region.
> > When there's only one device for both cores, it's not able to identify the memory region
> > by the device parameter of dma_allocate_coherent().
> >
> > Is it acceptable to consider manually allocating core 1 device in the probe() when probing core 0?
>
> Look at what Suman did for TI's K3 R5[1] and DSP[2] platforms.
> Reviewing the bindings for both platforms will also give you a good
> idea of how things work.
>
> [1]. https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_r5_remoteproc.c*L1683__;Iw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX30z0XV4vo3vCb9Wy-w5ixOTmzbv1akubM$
> [2]. https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_dsp_remoteproc.c*L673__;Iw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX30z0XV4vo3vCb9Wy-w5ixOTmzbfE2dtBg$
>
Hi Mathieu,
My plan is changing the dts as following,
scp core 0 {
// Keep current properties untouched.
compatible = "mediatek,mt8195-scp";
// core 0 properties...
// Add a new property for multi-core scp.
// if not present, it's single core.
// if present and core id = 0, it's the main core, otherwise the sub cores.
mediatek,scp-core = <0>;
// add sub cores as sub node.
// sub nodes can find parent by OF API.
scp core 1 {
// use the same compatile name as core 0.
compatible = "mediatek,mt8195-scp";
// assign id > 0 to sub cores.
mediatek,scp-core = <1>;
// core 1 properties...
};
};
The driver probe/remove behavior will be modified as below,
scp probe() {
// common init...
// check core id to have different memory mapping flow
if (core id == 0)
// mapping cfg, sram and others
else
// mapping sram
// reuse the cfg paddr/vaddr from core 0
// common init...
if (core id == 0) {
ret = of_platform_populate(...)
// boot core 0 and sub cores
rproc_add();
} else {
// add sub core as sub device to main core
rproc_add_subdev()
rproc->auto_boot = false;
rpoc_add();
}
}
scp_remove() {
if (core id == 0)
of_platform_depopulate()
else
rproc_remove_subdev()
// remove core
}
Best regards,
TingHan
On Mon, 19 Sept 2022 at 03:46, TingHan Shen <[email protected]> wrote:
>
> On Fri, 2022-09-16 at 11:15 -0600, Mathieu Poirier wrote:
> > On Fri, 16 Sept 2022 at 06:00, TingHan Shen <[email protected]> wrote:
> > >
> > > On Thu, 2022-09-08 at 14:58 -0600, Mathieu Poirier wrote:
> > > > On Thu, 8 Sept 2022 at 05:21, Tinghan Shen <[email protected]>
> > > > wrote:
> > > >
> > > > > Hi Mathieu,
> > > > >
> > > > > > > The mtk_scp.c driver only supports the single core SCP and the
> > > > > > > 1st core of a dual-core SCP. This patch extends it for the 2nd core.
> > > > > > >
> > > > > > > MT8195 SCP is a dual-core MCU. Both cores are housed in the same
> > > > >
> > > > > subsys.
> > > > > >
> > > > > > s/subsys/subsystem
> > > > > >
> > > > > > > They have the same viewpoint of registers and memory.
> > > > > > >
> > > > > > > Core 1 of the SCP features its own set of core configuration registers,
> > > > > > > interrupt controller, timers, and DMAs. The rest of the peripherals
> > > > > > > in this subsystem are shared by core 0 and core 1.
> > > > > > >
> > > > > > > As for memory, core 1 has its own cache memory. the SCP SRAM is shared
> > > > > >
> > > > > > /the/The
> > > > > >
> > > > > > > by core 0 and core 1.
> > > > > > >
> > > > > > > Signed-off-by: Tinghan Shen <[email protected]>
> > > > > > > ---
> > > > > > > drivers/remoteproc/mtk_scp.c | 22 ++++++++++++++++++++--
> > > > > > > 1 file changed, 20 insertions(+), 2 deletions(-)
> > > > > > >
> > > > > > > diff --git a/drivers/remoteproc/mtk_scp.c
> > > > >
> > > > > b/drivers/remoteproc/mtk_scp.c
> > > > > > > index 3510c6d0bbc8..91b4aefde4ac 100644
> > > > > > > --- a/drivers/remoteproc/mtk_scp.c
> > > > > > > +++ b/drivers/remoteproc/mtk_scp.c
> > > > > > > @@ -23,6 +23,10 @@
> > > > > > > #define MAX_CODE_SIZE 0x500000
> > > > > > > #define SECTION_NAME_IPI_BUFFER ".ipi_buffer"
> > > > > > >
> > > > > > > +#define SCP_CORE_0 0
> > > > > > > +#define SCP_CORE_1 1
> > > > > > > +#define SCP_CORE_SINGLE 0xF
> > > > > > > +
> > > > > > > /**
> > > > > > > * scp_get() - get a reference to SCP.
> > > > > > > *
> > > > > > > @@ -836,6 +840,7 @@ static int scp_probe(struct platform_device *pdev)
> > > > > > > struct resource *res;
> > > > > > > const char *fw_name = "scp.img";
> > > > > > > int ret, i;
> > > > > > > + u32 core_id = SCP_CORE_SINGLE;
> > > > > > >
> > > > > > > ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > > > > > > if (ret < 0 && ret != -EINVAL)
> > > > > > > @@ -851,8 +856,16 @@ static int scp_probe(struct platform_device *pdev)
> > > > > > > scp->data = of_device_get_match_data(dev);
> > > > > > > platform_set_drvdata(pdev, scp);
> > > > > > >
> > > > > > > + ret = of_property_read_u32_index(dev->of_node,
> > > > >
> > > > > "mediatek,scp-core", 1, &core_id);
> > > > > > > + if (ret == 0)
> > > > > > > + dev_info(dev, "Boot SCP dual core %u\n", core_id);
> > > > > >
> > > > > > Why is the DT property "mediatek,scp-core" needed at all? Since the
> > > > >
> > > > > compatible
> > > > > > "mediatek,mt8195-scp-dual" has already been defined previously in this
> > > > >
> > > > > patchset,
> > > > > > initialising the second core, if present, is a matter of looking at the
> > > > > > compatile string.
> > > > >
> > > > > This idea of identify cores by the compatible looks workable.
> > > > > I'll update this series at next version.
> > > > > Thanks!
> > > > >
> > > > > >
> > > > > > > +
> > > > > > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
> > > > > > > - scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > > > + if (core_id == SCP_CORE_1)
> > > > > > > + scp->sram_base = devm_ioremap(dev, res->start,
> > > > >
> > > > > resource_size(res));
> > > > > > > + else
> > > > > > > + scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > > > +
> > > > > >
> > > > > > This looks very broken... For this to work you would need to have two DT
> > > > > > entries with the "mediatek,mt8195-scp-dual" compatible properly, one with
> > > > > > "mediatek,scp-core = <&scp_dual1 0>;" and another one with
> > > > >
> > > > > "mediatek,scp-core = <&scp_dual0 1>;".
> > > > > >
> > > > > > Which is also very broken... Here you have a binding whose first
> > > > >
> > > > > argument is a
> > > > > > reference to the core sibling while the second argument is a
> > > > >
> > > > > characteristic of
> > > > > > the current core, which is highly confusing.
> > > > > >
> > > > > > I suggest what when you see the compatible binding
> > > > >
> > > > > "mediatek,mt8195-scp", a
> > > > > > single core is initialized. If you see "mediatek,mt8195-scp-dual", both
> > > > >
> > > > > cores
> > > > > > are initialized as part of the _same_ probe.
> > > > > >
> > > > > > If the above analysis is not correct it means I misinterpreted your
> > > > > > work and if so, a serious amount of comments is needed _and_ a very
> > > > >
> > > > > detailed
> > > > > > example in "mtk,scp.yaml" that leaves no room for interpretation.
> > > > > >
> > > > > > I will stop reviewing this patchset until you have clarified how this
> > > > >
> > > > > works.
> > > > > >
> > > > > > Thanks,
> > > > > > Mathieu
> > > > >
> > > > > There's one problem of initializng the CORE1 using the same probe flow.
> > > > > The register space of CORE0 and CORE1 are overlapped in the device node.
> > > > > Both cores need to use the 'cfg' registers defined in scp yaml.
> > > > > The devm_ioremap_resource catches address overlapping and returns error
> > > > > when
> > > > > probing CORE1 driver.
> > > > >
> > > >
> > > > That is exactly why I suggest to initialise both cores within the same
> > > > probe() function.
> > > >
> > >
> > > Hi Mathieu,
> > >
> > > I'm thinking about how to initialise in the same probe() function.
> > > I'm wondering if this implies that using one scp driver to initialize 2 cores?
> > > If it is, I assume the dts descriptions for both cores should be contained in one node.
> > >
> > > When there's one node for both cores, it looks like that there is a problem of
> > > using dma_allocate_coherent(). Each core has its own reserved memory region.
> > > When there's only one device for both cores, it's not able to identify the memory region
> > > by the device parameter of dma_allocate_coherent().
> > >
> > > Is it acceptable to consider manually allocating core 1 device in the probe() when probing core 0?
> >
> > Look at what Suman did for TI's K3 R5[1] and DSP[2] platforms.
> > Reviewing the bindings for both platforms will also give you a good
> > idea of how things work.
> >
> > [1]. https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_r5_remoteproc.c*L1683__;Iw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX30z0XV4vo3vCb9Wy-w5ixOTmzbv1akubM$
> > [2]. https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/remoteproc/ti_k3_dsp_remoteproc.c*L673__;Iw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX30z0XV4vo3vCb9Wy-w5ixOTmzbfE2dtBg$
> >
>
> Hi Mathieu,
>
> My plan is changing the dts as following,
>
> scp core 0 {
> // Keep current properties untouched.
> compatible = "mediatek,mt8195-scp";
>
> // core 0 properties...
>
> // Add a new property for multi-core scp.
> // if not present, it's single core.
> // if present and core id = 0, it's the main core, otherwise the sub cores.
> mediatek,scp-core = <0>;
>
> // add sub cores as sub node.
> // sub nodes can find parent by OF API.
> scp core 1 {
> // use the same compatile name as core 0.
> compatible = "mediatek,mt8195-scp";
>
> // assign id > 0 to sub cores.
> mediatek,scp-core = <1>;
>
> // core 1 properties...
> };
> };
>
>
> The driver probe/remove behavior will be modified as below,
>
> scp probe() {
> // common init...
>
> // check core id to have different memory mapping flow
> if (core id == 0)
> // mapping cfg, sram and others
> else
> // mapping sram
> // reuse the cfg paddr/vaddr from core 0
>
> // common init...
>
> if (core id == 0) {
> ret = of_platform_populate(...)
>
> // boot core 0 and sub cores
> rproc_add();
> } else {
> // add sub core as sub device to main core
> rproc_add_subdev()
>
> rproc->auto_boot = false;
> rpoc_add();
> }
> }
>
> scp_remove() {
>
> if (core id == 0)
> of_platform_depopulate()
> else
> rproc_remove_subdev()
>
> // remove core
> }
>
Unfortunately I do not have the bandwidth to look at inlined or pseudo
code. I will review this code with the next revision.
>
>
> Best regards,
> TingHan
>
>
>
>
> Subject: Re: [PATCH v2 4/9] remoteproc: mediatek: Support probing for the
> 2nd core of dual-core SCP
>
> On Fri, 2022-09-16 at 11:15 -0600, Mathieu Poirier wrote:
> > On Fri, 16 Sept 2022 at 06:00, TingHan Shen
> <[email protected]> wrote:
> > >
> > > On Thu, 2022-09-08 at 14:58 -0600, Mathieu Poirier wrote:
> > > > On Thu, 8 Sept 2022 at 05:21, Tinghan Shen
> > > > <[email protected]>
> > > > wrote:
> > > >
> > > > > Hi Mathieu,
> > > > >
> > > > > > > The mtk_scp.c driver only supports the single core SCP and
> > > > > > > the 1st core of a dual-core SCP. This patch extends it for the 2nd
> core.
> > > > > > >
> > > > > > > MT8195 SCP is a dual-core MCU. Both cores are housed in the
> > > > > > > same
> > > > >
> > > > > subsys.
> > > > > >
> > > > > > s/subsys/subsystem
> > > > > >
> > > > > > > They have the same viewpoint of registers and memory.
> > > > > > >
> > > > > > > Core 1 of the SCP features its own set of core configuration
> > > > > > > registers, interrupt controller, timers, and DMAs. The rest
> > > > > > > of the peripherals in this subsystem are shared by core 0 and
> core 1.
> > > > > > >
> > > > > > > As for memory, core 1 has its own cache memory. the SCP SRAM
> > > > > > > is shared
> > > > > >
> > > > > > /the/The
> > > > > >
> > > > > > > by core 0 and core 1.
> > > > > > >
> > > > > > > Signed-off-by: Tinghan Shen <[email protected]>
> > > > > > > ---
> > > > > > > drivers/remoteproc/mtk_scp.c | 22 ++++++++++++++++++++--
> > > > > > > 1 file changed, 20 insertions(+), 2 deletions(-)
> > > > > > >
> > > > > > > diff --git a/drivers/remoteproc/mtk_scp.c
> > > > >
> > > > > b/drivers/remoteproc/mtk_scp.c
> > > > > > > index 3510c6d0bbc8..91b4aefde4ac 100644
> > > > > > > --- a/drivers/remoteproc/mtk_scp.c
> > > > > > > +++ b/drivers/remoteproc/mtk_scp.c
> > > > > > > @@ -23,6 +23,10 @@
> > > > > > > #define MAX_CODE_SIZE 0x500000 #define
> > > > > > > SECTION_NAME_IPI_BUFFER ".ipi_buffer"
> > > > > > >
> > > > > > > +#define SCP_CORE_0 0
> > > > > > > +#define SCP_CORE_1 1
> > > > > > > +#define SCP_CORE_SINGLE 0xF
> > > > > > > +
> > > > > > > /**
> > > > > > > * scp_get() - get a reference to SCP.
> > > > > > > *
> > > > > > > @@ -836,6 +840,7 @@ static int scp_probe(struct
> platform_device *pdev)
> > > > > > > struct resource *res;
> > > > > > > const char *fw_name = "scp.img";
> > > > > > > int ret, i;
> > > > > > > + u32 core_id = SCP_CORE_SINGLE;
> > > > > > >
> > > > > > > ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > > > > > > if (ret < 0 && ret != -EINVAL) @@ -851,8 +856,16 @@
> > > > > > > static int scp_probe(struct platform_device *pdev)
> > > > > > > scp->data = of_device_get_match_data(dev);
> > > > > > > platform_set_drvdata(pdev, scp);
> > > > > > >
> > > > > > > + ret = of_property_read_u32_index(dev->of_node,
> > > > >
> > > > > "mediatek,scp-core", 1, &core_id);
> > > > > > > + if (ret == 0)
> > > > > > > + dev_info(dev, "Boot SCP dual core %u\n",
> > > > > > > + core_id);
> > > > > >
> > > > > > Why is the DT property "mediatek,scp-core" needed at all?
> > > > > > Since the
> > > > >
> > > > > compatible
> > > > > > "mediatek,mt8195-scp-dual" has already been defined previously
> > > > > > in this
> > > > >
> > > > > patchset,
> > > > > > initialising the second core, if present, is a matter of
> > > > > > looking at the compatile string.
> > > > >
> > > > > This idea of identify cores by the compatible looks workable.
> > > > > I'll update this series at next version.
> > > > > Thanks!
> > > > >
> > > > > >
> > > > > > > +
> > > > > > > res = platform_get_resource_byname(pdev,
> IORESOURCE_MEM, "sram");
> > > > > > > - scp->sram_base = devm_ioremap_resource(dev, res);
> > > > > > > + if (core_id == SCP_CORE_1)
> > > > > > > + scp->sram_base = devm_ioremap(dev, res->start,
> > > > >
> > > > > resource_size(res));
> > > > > > > + else
> > > > > > > + scp->sram_base = devm_ioremap_resource(dev,
> > > > > > > + res);
> > > > > > > +
> > > > > >
> > > > > > This looks very broken... For this to work you would need to
> > > > > > have two DT entries with the "mediatek,mt8195-scp-dual"
> > > > > > compatible properly, one with "mediatek,scp-core = <&scp_dual1
> > > > > > 0>;" and another one with
> > > > >
> > > > > "mediatek,scp-core = <&scp_dual0 1>;".
> > > > > >
> > > > > > Which is also very broken... Here you have a binding whose
> > > > > > first
> > > > >
> > > > > argument is a
> > > > > > reference to the core sibling while the second argument is a
> > > > >
> > > > > characteristic of
> > > > > > the current core, which is highly confusing.
> > > > > >
> > > > > > I suggest what when you see the compatible binding
> > > > >
> > > > > "mediatek,mt8195-scp", a
> > > > > > single core is initialized. If you see
> > > > > > "mediatek,mt8195-scp-dual", both
> > > > >
> > > > > cores
> > > > > > are initialized as part of the _same_ probe.
> > > > > >
> > > > > > If the above analysis is not correct it means I misinterpreted
> > > > > > your work and if so, a serious amount of comments is needed
> > > > > > _and_ a very
> > > > >
> > > > > detailed
> > > > > > example in "mtk,scp.yaml" that leaves no room for interpretation.
> > > > > >
> > > > > > I will stop reviewing this patchset until you have clarified
> > > > > > how this
> > > > >
> > > > > works.
> > > > > >
> > > > > > Thanks,
> > > > > > Mathieu
> > > > >
> > > > > There's one problem of initializng the CORE1 using the same probe
> flow.
> > > > > The register space of CORE0 and CORE1 are overlapped in the device
> node.
> > > > > Both cores need to use the 'cfg' registers defined in scp yaml.
> > > > > The devm_ioremap_resource catches address overlapping and
> > > > > returns error when probing CORE1 driver.
> > > > >
> > > >
> > > > That is exactly why I suggest to initialise both cores within the same
> > > > probe() function.
> > > >
> > >
> > > Hi Mathieu,
> > >
> > > I'm thinking about how to initialise in the same probe() function.
> > > I'm wondering if this implies that using one scp driver to initialize 2 cores?
> > > If it is, I assume the dts descriptions for both cores should be contained
> in one node.
> > >
> > > When there's one node for both cores, it looks like that there is a
> problem of
> > > using dma_allocate_coherent(). Each core has its own reserved memory
> region.
> > > When there's only one device for both cores, it's not able to identify the
> memory region
> > > by the device parameter of dma_allocate_coherent().
> > >
> > > Is it acceptable to consider manually allocating core 1 device in the
> probe() when probing core 0?
> >
> > Look at what Suman did for TI's K3 R5[1] and DSP[2] platforms.
> > Reviewing the bindings for both platforms will also give you a good
> > idea of how things work.
> >
> > [1].
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Furlde
> fense.com%2Fv3%2F__https%3A%2F%2Felixir.bootlin.com%2Flinux%2Fv6.0-
> rc5%2Fsource%2Fdrivers%2Fremoteproc%2Fti_k3_r5_remoteproc.c*L1683_
> _%3BIw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX3
> 0z0XV4vo3vCb9Wy-
> w5ixOTmzbv1akubM%24&data=05%7C01%7Cpeng.fan%40nxp.com%7
> C2cf76b2f15544cf3d06308da9a23f00a%7C686ea1d3bc2b4c6fa92cd99c5c301
> 635%7C0%7C0%7C637991776400238974%7CUnknown%7CTWFpbGZsb3d8e
> yJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D
> %7C3000%7C%7C%7C&sdata=dz0FlQQmKI4C67XCX%2BZ6%2Bin%2Btq
> 2DEWLb5YA%2FxGLOxHc%3D&reserved=0
> > [2].
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Furlde
> fense.com%2Fv3%2F__https%3A%2F%2Felixir.bootlin.com%2Flinux%2Fv6.0-
> rc5%2Fsource%2Fdrivers%2Fremoteproc%2Fti_k3_dsp_remoteproc.c*L673_
> _%3BIw!!CTRNKA9wMg0ARbw!zVcjdLSfKYGO5YQMNGqq339mle8u0VdULX3
> 0z0XV4vo3vCb9Wy-
> w5ixOTmzbfE2dtBg%24&data=05%7C01%7Cpeng.fan%40nxp.com%7C
> 2cf76b2f15544cf3d06308da9a23f00a%7C686ea1d3bc2b4c6fa92cd99c5c3016
> 35%7C0%7C0%7C637991776400238974%7CUnknown%7CTWFpbGZsb3d8ey
> JWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D
> %7C3000%7C%7C%7C&sdata=Yn7MOo2uoDOVRW47O1yq8W3c%2BYg
> G5URr7RdLKsmpLrk%3D&reserved=0
> >
>
> Hi Mathieu,
>
> My plan is changing the dts as following,
>
> scp core 0 {
> // Keep current properties untouched.
> compatible = "mediatek,mt8195-scp";
>
> // core 0 properties...
>
> // Add a new property for multi-core scp.
> // if not present, it's single core.
> // if present and core id = 0, it's the main core, otherwise the sub
> cores.
> mediatek,scp-core = <0>;
>
> // add sub cores as sub node.
> // sub nodes can find parent by OF API.
> scp core 1 {
> // use the same compatile name as core 0.
> compatible = "mediatek,mt8195-scp";
>
> // assign id > 0 to sub cores.
> mediatek,scp-core = <1>;
>
> // core 1 properties...
> };
> };
Not know the HW arch, but this looks a bit weird, scp core 1 is
a sub node of scp core 0.
>
>
> The driver probe/remove behavior will be modified as below,
>
> scp probe() {
> // common init...
>
> // check core id to have different memory mapping flow
> if (core id == 0)
> // mapping cfg, sram and others
> else
> // mapping sram
> // reuse the cfg paddr/vaddr from core 0
Oh, I understand why you need ioremap_resource, so core0/1 share
same register address space?
Regards,
Peng.
>
> // common init...
>
> if (core id == 0) {
> ret = of_platform_populate(...)
>
> // boot core 0 and sub cores
> rproc_add();
> } else {
> // add sub core as sub device to main core
> rproc_add_subdev()
>
> rproc->auto_boot = false;
> rpoc_add();
> }
> }
>
> scp_remove() {
>
> if (core id == 0)
> of_platform_depopulate()
> else
> rproc_remove_subdev()
>
> // remove core
> }
>
>
>
> Best regards,
> TingHan
>
>
>