This feature is telling how to configure cache type on 4 different
transfer types: Data Read, Desc Read, Data Write and Desc write. For each
treasfer type, controller has a 4-bit register field to enable different
cache type. Quoted from DWC3 data book Table 6-5 Cache Type Bit Assignments:
----------------------------------------------------------------
MBUS_TYPE| bit[3] |bit[2] |bit[1] |bit[0]
----------------------------------------------------------------
AHB |Cacheable |Bufferable |Privilegge |Data
AXI3 |Write Allocate|Read Allocate|Cacheable |Bufferable
AXI4 |Allocate Other|Allocate |Modifiable |Bufferable
AXI4 |Other Allocate|Allocate |Modifiable |Bufferable
Native |Same as AXI |Same as AXI |Same as AXI|Same as AXI
----------------------------------------------------------------
Note: The AHB, AXI3, AXI4, and PCIe busses use different names for certain
signals, which have the same meaning:
Bufferable = Posted
Cacheable = Modifiable = Snoop (negation of No Snoop)
In most cases, driver support is not required unless the default values of
registers are not correct *and* DWC3 node has enabled dma-coherent. So far we
have observed USB device detect failure on some Layerscape platforms if this
programming was not applied.
Related struct:
struct dwc3_cache_type {
u8 transfer_type_datard;
u8 transfer_type_descrd;
u8 transfer_type_datawr;
u8 transfer_type_descwr;
};
Signed-off-by: Ran Wang <ran.wang_1@xxxxxxx>
---
Change in v3:
- Replace cache type sub-node parsing with chip-specifc data parsing.
Change in v2:
- Change most program logic to meet new DTS property define.
- Rename related register address macros.
- Rename function dwc3_enable_snooping() to dwc3_set_cache_type().
drivers/usb/dwc3/core.c | 67 ++++++++++++++++++++++++++++++++++++++++++++-----
drivers/usb/dwc3/core.h | 15 +++++++++++
2 files changed, 76 insertions(+), 6 deletions(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 97d6ae3..0baa972 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -894,6 +894,53 @@ static void dwc3_set_incr_burst_type(struct dwc3 *dwc)
dwc3_writel(dwc->regs, DWC3_GSBUSCFG0, cfg);
}
+#ifdef CONFIG_OF
+struct dwc3_cache_type {
+ u8 transfer_type_datard;
+ u8 transfer_type_descrd;
+ u8 transfer_type_datawr;
+ u8 transfer_type_descwr;
+};
+
+static const struct dwc3_cache_type ls1088a_dwc3_cache_type = {
+ .transfer_type_datard = 2,
+ .transfer_type_descrd = 2,
+ .transfer_type_datawr = 2,
+ .transfer_type_descwr = 2,
+};
+
+/**
+ * dwc3_set_cache_type - Configure cache type registers
+ * @dwc: Pointer to our controller context structure
+ */
+static void dwc3_set_cache_type(struct dwc3 *dwc)
+{
+ u32 tmp, reg;
+ const struct dwc3_cache_type *cache_type =
+ device_get_match_data(dwc->dev);
+
+ if (cache_type) {
+ reg = dwc3_readl(dwc->regs, DWC3_GSBUSCFG0);
+ tmp = reg;
+
+ reg &= ~DWC3_GSBUSCFG0_DATARD(~0);
+ reg |= DWC3_GSBUSCFG0_DATARD(cache_type->transfer_type_datard);
+
+ reg &= ~DWC3_GSBUSCFG0_DESCRD(~0);
+ reg |= DWC3_GSBUSCFG0_DESCRD(cache_type->transfer_type_descrd);
+
+ reg &= ~DWC3_GSBUSCFG0_DATAWR(~0);
+ reg |= DWC3_GSBUSCFG0_DATAWR(cache_type->transfer_type_datawr);
+
+ reg &= ~DWC3_GSBUSCFG0_DESCWR(~0);
+ reg |= DWC3_GSBUSCFG0_DESCWR(cache_type->transfer_type_descwr);
+
+ if (tmp != reg)
+ dwc3_writel(dwc->regs, DWC3_GSBUSCFG0, reg);
+ }
+}
+#endif
+
/**
* dwc3_core_init - Low-level initialization of DWC3 Core
* @dwc: Pointer to our controller context structure
@@ -952,6 +999,10 @@ static int dwc3_core_init(struct dwc3 *dwc)
dwc3_set_incr_burst_type(dwc);
+#ifdef CONFIG_OF
+ dwc3_set_cache_type(dwc);
+#endif
+
usb_phy_set_suspend(dwc->usb2_phy, 0);
usb_phy_set_suspend(dwc->usb3_phy, 0);
ret = phy_power_on(dwc->usb2_generic_phy);
@@ -1837,12 +1888,16 @@ static const struct dev_pm_ops dwc3_dev_pm_ops = {
#ifdef CONFIG_OF
static const struct of_device_id of_dwc3_match[] = {
- {
- .compatible = "snps,dwc3"
- },
- {
- .compatible = "synopsys,dwc3"
- },
+ { .compatible = "fsl,ls1012a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls1021a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls1028a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls1043a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls1046a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls1088a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,ls2088a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "fsl,lx2160a-dwc3", .data = &ls1088a_dwc3_cache_type, },
+ { .compatible = "snps,dwc3" },
+ { .compatible = "synopsys,dwc3" },
{ },
};
MODULE_DEVICE_TABLE(of, of_dwc3_match);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 1c8b3493..ac51dfe 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -165,6 +165,21 @@
/* Bit fields */
/* Global SoC Bus Configuration INCRx Register 0 */
+#ifdef CONFIG_OF
+#define DWC3_GSBUSCFG0_DATARD_SHIFT 28
+#define DWC3_GSBUSCFG0_DATARD(n) (((n) & 0xf) \
+ << DWC3_GSBUSCFG0_DATARD_SHIFT)
+#define DWC3_GSBUSCFG0_DESCRD_SHIFT 24
+#define DWC3_GSBUSCFG0_DESCRD(n) (((n) & 0xf) \
+ << DWC3_GSBUSCFG0_DESCRD_SHIFT)
+#define DWC3_GSBUSCFG0_DATAWR_SHIFT 20
+#define DWC3_GSBUSCFG0_DATAWR(n) (((n) & 0xf) \
+ << DWC3_GSBUSCFG0_DATAWR_SHIFT)
+#define DWC3_GSBUSCFG0_DESCWR_SHIFT 16
+#define DWC3_GSBUSCFG0_DESCWR(n) (((n) & 0xf) \
+ << DWC3_GSBUSCFG0_DESCWR_SHIFT)
+#endif
+
#define DWC3_GSBUSCFG0_INCR256BRSTENA (1 << 7) /* INCR256 burst */
#define DWC3_GSBUSCFG0_INCR128BRSTENA (1 << 6) /* INCR128 burst */
#define DWC3_GSBUSCFG0_INCR64BRSTENA (1 << 5) /* INCR64 burst */
--
2.7.4
