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authorMinas Harutyunyan <Minas.Harutyunyan@synopsys.com>2020-05-21 10:05:44 +0400
committerFelipe Balbi <balbi@kernel.org>2020-05-25 11:09:44 +0300
commit65dc2e725286106f99c6f6b78e3d9c52c15f3a9c (patch)
tree267a2f9b4db38c3354448e3ad17a5774896b188b /drivers/usb/dwc2/platform.c
parent4cda340a455b425f7df9657aaaa78a75757d940d (diff)
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usb: dwc2: Update Core Reset programming flow.
Starting from core version 4.20a Core Reset flow is changed. Introduced new bit in GRSTCTL register - GRSTCTL_CSFTRST_DONE. Core Reset new programming flow steps are follow: 1. Set GRSTCTL_CSFTRST bit. 2. Wait for bit GRSTCTL_CSFTRST_DONE is set. 3. Clear GRSTCTL_CSFTRST and GRSTCTL_CSFTRST_DONE bits. Check core version functionality separated from dwc2_get_hwparams() to new dwc2_check_core_version() function because Core Reset flow depend on SNPSID. Signed-off-by: Minas Harutyunyan <hminas@synopsys.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
Diffstat (limited to 'drivers/usb/dwc2/platform.c')
-rw-r--r--drivers/usb/dwc2/platform.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 69972750e161..e571c8ae65ec 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -363,6 +363,37 @@ static bool dwc2_check_core_endianness(struct dwc2_hsotg *hsotg)
}
/**
+ * Check core version
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ */
+int dwc2_check_core_version(struct dwc2_hsotg *hsotg)
+{
+ struct dwc2_hw_params *hw = &hsotg->hw_params;
+
+ /*
+ * Attempt to ensure this device is really a DWC_otg Controller.
+ * Read and verify the GSNPSID register contents. The value should be
+ * 0x45f4xxxx, 0x5531xxxx or 0x5532xxxx
+ */
+
+ hw->snpsid = dwc2_readl(hsotg, GSNPSID);
+ if ((hw->snpsid & GSNPSID_ID_MASK) != DWC2_OTG_ID &&
+ (hw->snpsid & GSNPSID_ID_MASK) != DWC2_FS_IOT_ID &&
+ (hw->snpsid & GSNPSID_ID_MASK) != DWC2_HS_IOT_ID) {
+ dev_err(hsotg->dev, "Bad value for GSNPSID: 0x%08x\n",
+ hw->snpsid);
+ return -ENODEV;
+ }
+
+ dev_dbg(hsotg->dev, "Core Release: %1x.%1x%1x%1x (snpsid=%x)\n",
+ hw->snpsid >> 12 & 0xf, hw->snpsid >> 8 & 0xf,
+ hw->snpsid >> 4 & 0xf, hw->snpsid & 0xf, hw->snpsid);
+ return 0;
+}
+
+/**
* dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg
* driver
*
@@ -445,6 +476,14 @@ static int dwc2_driver_probe(struct platform_device *dev)
"snps,need-phy-for-wake");
/*
+ * Before performing any core related operations
+ * check core version.
+ */
+ retval = dwc2_check_core_version(hsotg);
+ if (retval)
+ goto error;
+
+ /*
* Reset before dwc2_get_hwparams() then it could get power-on real
* reset value form registers.
*/