>-----Original Message----- >From: Graeme Gregory [mailto:gg@xxxxxxxxxxxxxxx] >Sent: Friday, December 04, 2015 9:16 PM >To: Wang, Annie >Cc: Vinod Koul; Mika Westerberg; Joerg Roedel; Greg Kroah-Hartman; Rafael J. >Wysocki; linux-acpi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux- >serial@xxxxxxxxxxxxxxx; dmaengine@xxxxxxxxxxxxxxx; iommu@lists.linux- >foundation.org; Borislav Petkov; Huang, Ray; Wan, Vincent; Xue, Ken; Li, Tony >Subject: Re: [PATCH 3/9] ACPI: add struct acpi_amba_quirk for AMD pl330 >specific device config > >On Fri, Dec 04, 2015 at 11:24:20AM +0800, Wang Hongcheng wrote: >> AMD pl330 is a UART DMA device, it shares one ACPI item with UART. So >> a platform device and an acpi device will be created according to >> AMD0020 ACPI dev. And its mem base address must have an offset. As a >> result, MULTI_ATTACHED_QUIRK and MULTI_ATTACHED_QUIRK are used. >> >> Signed-off-by: Wang Hongcheng <annie.wang@xxxxxxx> >> --- >> drivers/acpi/acpi_amba.c | 31 +++++++++++++++++++++++---- >> drivers/acpi/acpi_apd.c | 56 +++++++++++++++++++++++++++++++++++++------ >----- >> include/linux/acpi.h | 13 +++++++++-- >> 3 files changed, 81 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/acpi/acpi_amba.c b/drivers/acpi/acpi_amba.c index >> 4f0366a..8a5269c 100644 >> --- a/drivers/acpi/acpi_amba.c >> +++ b/drivers/acpi/acpi_amba.c >> @@ -31,6 +31,8 @@ ACPI_MODULE_NAME("amba"); >> * @periphid: AMBA device periphid. >> * @fixed_rate: Clock frequency. >> * @pdata: Platform data specific to the device. >> + * @quirk: Specific device config, including device multiattach. >> + * and mem base offset. >> * >> * Check if the given @adev can be represented as an AMBA device and, if >> * that's the case, create and register an AMBA device, populate its >> @@ -42,7 +44,8 @@ ACPI_MODULE_NAME("amba"); struct amba_device >> *acpi_create_amba_device(struct acpi_device *adev, >> unsigned int periphid, >> unsigned long fixed_rate, >> - void *pdata) >> + void *pdata, >> + struct acpi_amba_quirk *quirk) >> { >> struct amba_device *amba_dev = NULL; >> struct device *parent; >> @@ -54,12 +57,14 @@ struct amba_device *acpi_create_amba_device(struct >acpi_device *adev, >> unsigned int i; >> unsigned int irq[AMBA_NR_IRQS]; >> struct clk *clk = ERR_PTR(-ENODEV); >> + char amba_devname[100]; >> >> /* >> * If the ACPI node already has a physical device attached, >> - * skip it. >> + * skip it. Except some special devices such as AMD0020 which >> + * needs attach physical devices two times. >> */ >> - if (adev->physical_node_count) >> + if (adev->physical_node_count && !(quirk->quirk & >> +MULTI_ATTACHED_QUIRK)) >> return NULL; >> >> INIT_LIST_HEAD(&resource_list); >> @@ -85,7 +90,24 @@ struct amba_device *acpi_create_amba_device(struct >acpi_device *adev, >> memcpy(resource, rentry->res, sizeof(struct resource)); >> } >> >> - amba_dev = amba_device_alloc(dev_name(&adev->dev), >> + /* >> + * The memory address of AMD pl330 has an offset of ACPI >> + * mem resource. >> + */ >> + if (quirk->quirk & BASE_OFFSET_QUIRK) >> + resource->start += quirk->base_offset; >> + >> + /* >> + * If the ACPI device already has a node attached. It must be >> + * renamed. >> + */ >> + if (quirk->quirk & MULTI_ATTACHED_QUIRK) >> + sprintf(amba_devname, "%s%s", dev_name(&adev->dev), >"DMA"); >> + else >> + memcpy(amba_devname, dev_name(&adev->dev), >> + strlen(dev_name(&adev->dev))); >> + >> + amba_dev = amba_device_alloc(amba_devname, >> resource->start, >> resource_size(resource)); >> > >Isn't this basially an MFD in a rather odd fashion? > >I would have though having a device which just splits the resources then creates 2 >children would be a whole lot simpler? > >Graeme It seems more complex, if I trans an ACPI device to pdev, then attach 2 platform child nodes, and create an amba device refer to one of the childs. Too many trans. Thanks, Hongcheng(Annie) -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
