Re: [v5,4/6] usb: xhci: use bus->sysdev for DMA configuration

From: Alexander Sverdlin
Date: Tue Dec 13 2016 - 16:44:50 EST


Hi!

On 17/11/16 12:43, Sriram Dash wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> For xhci-hcd platform device, all the DMA parameters are not
> configured properly, notably dma ops for dwc3 devices. So, set
> the dma for xhci from sysdev. sysdev is pointing to device that
> is known to the system firmware or hardware.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Signed-off-by: Sriram Dash <sriram.dash@xxxxxxx>
> Tested-by: Baolin Wang <baolin.wang@xxxxxxxxxx>

Successfully tested on arm64/axxia with DWC3 USB host, XHCIs properly inherit
DMA configuration. Therefore:

Tested-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>

> ---
> Changes in v5:
> - No update
>
> Changes in v4:
> - No update
>
> Changes in v3:
> - No update
>
> Changes in v2:
> - Separate out xhci driver changes apart
>
> drivers/usb/host/xhci-mem.c | 12 ++++++------
> drivers/usb/host/xhci-plat.c | 33 ++++++++++++++++++++++++++-------
> drivers/usb/host/xhci.c | 15 +++++++++++----
> 3 files changed, 43 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
> index 48a26d378..eb32de9 100644
> --- a/drivers/usb/host/xhci-mem.c
> +++ b/drivers/usb/host/xhci-mem.c
> @@ -586,7 +586,7 @@ static void xhci_free_stream_ctx(struct xhci_hcd *xhci,
> unsigned int num_stream_ctxs,
> struct xhci_stream_ctx *stream_ctx, dma_addr_t dma)
> {
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
> size_t size = sizeof(struct xhci_stream_ctx) * num_stream_ctxs;
>
> if (size > MEDIUM_STREAM_ARRAY_SIZE)
> @@ -614,7 +614,7 @@ static struct xhci_stream_ctx *xhci_alloc_stream_ctx(struct xhci_hcd *xhci,
> unsigned int num_stream_ctxs, dma_addr_t *dma,
> gfp_t mem_flags)
> {
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
> size_t size = sizeof(struct xhci_stream_ctx) * num_stream_ctxs;
>
> if (size > MEDIUM_STREAM_ARRAY_SIZE)
> @@ -1644,7 +1644,7 @@ void xhci_slot_copy(struct xhci_hcd *xhci,
> static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
> {
> int i;
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
> int num_sp = HCS_MAX_SCRATCHPAD(xhci->hcs_params2);
>
> xhci_dbg_trace(xhci, trace_xhci_dbg_init,
> @@ -1716,7 +1716,7 @@ static void scratchpad_free(struct xhci_hcd *xhci)
> {
> int num_sp;
> int i;
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
>
> if (!xhci->scratchpad)
> return;
> @@ -1792,7 +1792,7 @@ void xhci_free_command(struct xhci_hcd *xhci,
>
> void xhci_mem_cleanup(struct xhci_hcd *xhci)
> {
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
> int size;
> int i, j, num_ports;
>
> @@ -2334,7 +2334,7 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
> int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
> {
> dma_addr_t dma;
> - struct device *dev = xhci_to_hcd(xhci)->self.controller;
> + struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
> unsigned int val, val2;
> u64 val_64;
> struct xhci_segment *seg;
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index ed56bf9..beb95c8 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -14,6 +14,7 @@
> #include <linux/clk.h>
> #include <linux/dma-mapping.h>
> #include <linux/module.h>
> +#include <linux/pci.h>
> #include <linux/of.h>
> #include <linux/platform_device.h>
> #include <linux/usb/phy.h>
> @@ -139,6 +140,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
> {
> const struct of_device_id *match;
> const struct hc_driver *driver;
> + struct device *sysdev;
> struct xhci_hcd *xhci;
> struct resource *res;
> struct usb_hcd *hcd;
> @@ -155,22 +157,39 @@ static int xhci_plat_probe(struct platform_device *pdev)
> if (irq < 0)
> return -ENODEV;
>
> + /*
> + * sysdev must point to a device that is known to the system firmware
> + * or PCI hardware. We handle these three cases here:
> + * 1. xhci_plat comes from firmware
> + * 2. xhci_plat is child of a device from firmware (dwc3-plat)
> + * 3. xhci_plat is grandchild of a pci device (dwc3-pci)
> + */
> + sysdev = &pdev->dev;
> + if (sysdev->parent && !sysdev->of_node && sysdev->parent->of_node)
> + sysdev = sysdev->parent;
> +#ifdef CONFIG_PCI
> + else if (sysdev->parent && sysdev->parent->parent &&
> + sysdev->parent->parent->bus == &pci_bus_type)
> + sysdev = sysdev->parent->parent;
> +#endif
> +
> /* Try to set 64-bit DMA first */
> - if (WARN_ON(!pdev->dev.dma_mask))
> + if (WARN_ON(!sysdev->dma_mask))
> /* Platform did not initialize dma_mask */
> - ret = dma_coerce_mask_and_coherent(&pdev->dev,
> + ret = dma_coerce_mask_and_coherent(sysdev,
> DMA_BIT_MASK(64));
> else
> - ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> + ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
>
> /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */
> if (ret) {
> - ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + ret = dma_set_mask_and_coherent(sysdev, DMA_BIT_MASK(32));
> if (ret)
> return ret;
> }
>
> - hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
> + hcd = __usb_create_hcd(driver, sysdev, &pdev->dev,
> + dev_name(&pdev->dev), NULL);
> if (!hcd)
> return -ENOMEM;
>
> @@ -220,13 +239,13 @@ static int xhci_plat_probe(struct platform_device *pdev)
> goto disable_clk;
> }
>
> - if (device_property_read_bool(&pdev->dev, "usb3-lpm-capable"))
> + if (device_property_read_bool(sysdev, "usb3-lpm-capable"))
> xhci->quirks |= XHCI_LPM_SUPPORT;
>
> if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
> xhci->shared_hcd->can_do_streams = 1;
>
> - hcd->usb_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
> + hcd->usb_phy = devm_usb_get_phy_by_phandle(sysdev, "usb-phy", 0);
> if (IS_ERR(hcd->usb_phy)) {
> ret = PTR_ERR(hcd->usb_phy);
> if (ret == -EPROBE_DEFER)
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index cf30cb6..fc76671 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -231,6 +231,9 @@ static int xhci_free_msi(struct xhci_hcd *xhci)
> static int xhci_setup_msi(struct xhci_hcd *xhci)
> {
> int ret;
> + /*
> + * TODO:Check with MSI Soc for sysdev
> + */
> struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
>
> ret = pci_enable_msi(pdev);
> @@ -257,7 +260,7 @@ static int xhci_setup_msi(struct xhci_hcd *xhci)
> */
> static void xhci_free_irq(struct xhci_hcd *xhci)
> {
> - struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
> + struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.sysdev);
> int ret;
>
> /* return if using legacy interrupt */
> @@ -743,7 +746,7 @@ void xhci_shutdown(struct usb_hcd *hcd)
> struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>
> if (xhci->quirks & XHCI_SPURIOUS_REBOOT)
> - usb_disable_xhci_ports(to_pci_dev(hcd->self.controller));
> + usb_disable_xhci_ports(to_pci_dev(hcd->self.sysdev));
>
> spin_lock_irq(&xhci->lock);
> xhci_halt(xhci);
> @@ -760,7 +763,7 @@ void xhci_shutdown(struct usb_hcd *hcd)
>
> /* Yet another workaround for spurious wakeups at shutdown with HSW */
> if (xhci->quirks & XHCI_SPURIOUS_WAKEUP)
> - pci_set_power_state(to_pci_dev(hcd->self.controller), PCI_D3hot);
> + pci_set_power_state(to_pci_dev(hcd->self.sysdev), PCI_D3hot);
> }
>
> #ifdef CONFIG_PM
> @@ -4832,7 +4835,11 @@ int xhci_get_frame(struct usb_hcd *hcd)
> int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
> {
> struct xhci_hcd *xhci;
> - struct device *dev = hcd->self.controller;
> + /*
> + * TODO: Check with DWC3 clients for sysdev according to
> + * quirks
> + */
> + struct device *dev = hcd->self.sysdev;
> int retval;
>
> /* Accept arbitrarily long scatter-gather lists */
>

--
Best regards,
Alexander Sverdlin.