usb: dwc3: core: allocate scratch buffers
We must read HWPARAMS4 register to figure out
how many scratch buffers we should allocate.
Later patch will use "Set Scratchpad Buffer
Array" command to pass the pointer to the
IP so it can be used during hibernation.
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 785feee..8c627c9 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -242,6 +242,90 @@
}
}
+static int dwc3_alloc_scratch_buffers(struct dwc3 *dwc)
+{
+ if (!dwc->has_hibernation)
+ return 0;
+
+ if (!dwc->nr_scratch)
+ return 0;
+
+ dwc->scratchbuf = kmalloc_array(dwc->nr_scratch,
+ DWC3_SCRATCHBUF_SIZE, GFP_KERNEL);
+ if (!dwc->scratchbuf)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int dwc3_setup_scratch_buffers(struct dwc3 *dwc)
+{
+ dma_addr_t scratch_addr;
+ u32 param;
+ int ret;
+
+ if (!dwc->has_hibernation)
+ return 0;
+
+ if (!dwc->nr_scratch)
+ return 0;
+
+ /* should never fall here */
+ if (!WARN_ON(dwc->scratchbuf))
+ return 0;
+
+ scratch_addr = dma_map_single(dwc->dev, dwc->scratchbuf,
+ dwc->nr_scratch * DWC3_SCRATCHBUF_SIZE,
+ DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(dwc->dev, scratch_addr)) {
+ dev_err(dwc->dev, "failed to map scratch buffer\n");
+ ret = -EFAULT;
+ goto err0;
+ }
+
+ dwc->scratch_addr = scratch_addr;
+
+ param = lower_32_bits(scratch_addr);
+
+ ret = dwc3_send_gadget_generic_command(dwc,
+ DWC3_DGCMD_SET_SCRATCHPAD_ADDR_LO, param);
+ if (ret < 0)
+ goto err1;
+
+ param = upper_32_bits(scratch_addr);
+
+ ret = dwc3_send_gadget_generic_command(dwc,
+ DWC3_DGCMD_SET_SCRATCHPAD_ADDR_HI, param);
+ if (ret < 0)
+ goto err1;
+
+ return 0;
+
+err1:
+ dma_unmap_single(dwc->dev, dwc->scratch_addr, dwc->nr_scratch *
+ DWC3_SCRATCHBUF_SIZE, DMA_BIDIRECTIONAL);
+
+err0:
+ return ret;
+}
+
+static void dwc3_free_scratch_buffers(struct dwc3 *dwc)
+{
+ if (!dwc->has_hibernation)
+ return;
+
+ if (!dwc->nr_scratch)
+ return;
+
+ /* should never fall here */
+ if (!WARN_ON(dwc->scratchbuf))
+ return;
+
+ dma_unmap_single(dwc->dev, dwc->scratch_addr, dwc->nr_scratch *
+ DWC3_SCRATCHBUF_SIZE, DMA_BIDIRECTIONAL);
+ kfree(dwc->scratchbuf);
+}
+
static void dwc3_core_num_eps(struct dwc3 *dwc)
{
struct dwc3_hwparams *parms = &dwc->hwparams;
@@ -277,6 +361,7 @@
static int dwc3_core_init(struct dwc3 *dwc)
{
unsigned long timeout;
+ u32 hwparams4 = dwc->hwparams.hwparams4;
u32 reg;
int ret;
@@ -334,6 +419,10 @@
else
reg &= ~DWC3_GCTL_DSBLCLKGTNG;
break;
+ case DWC3_GHWPARAMS1_EN_PWROPT_HIB:
+ /* enable hibernation here */
+ dwc->nr_scratch = DWC3_GHWPARAMS4_HIBER_SCRATCHBUFS(hwparams4);
+ break;
default:
dev_dbg(dwc->dev, "No power optimization available\n");
}
@@ -351,14 +440,30 @@
dwc3_writel(dwc->regs, DWC3_GCTL, reg);
+ ret = dwc3_alloc_scratch_buffers(dwc);
+ if (ret)
+ goto err1;
+
+ ret = dwc3_setup_scratch_buffers(dwc);
+ if (ret)
+ goto err2;
+
return 0;
+err2:
+ dwc3_free_scratch_buffers(dwc);
+
+err1:
+ usb_phy_shutdown(dwc->usb2_phy);
+ usb_phy_shutdown(dwc->usb3_phy);
+
err0:
return ret;
}
static void dwc3_core_exit(struct dwc3 *dwc)
{
+ dwc3_free_scratch_buffers(dwc);
usb_phy_shutdown(dwc->usb2_phy);
usb_phy_shutdown(dwc->usb3_phy);
}