Re: [PATCH v2 2/5] phy: phy-mtk-tphy: add support efuse setting

From: AngeloGioacchino Del Regno
Date: Fri Dec 24 2021 - 05:04:03 EST


Il 18/12/21 09:27, Chunfeng Yun ha scritto:
Due to some SoCs have a bit shift issue that will drop a bit for usb3
phy or pcie phy, fix it by adding software efuse reading and setting,
but only support it optionally for version 2/3.

Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
---
v2: changes suggested by Vinod
1. fix typo of version in commit message
2. use dev_dbg() instead of dev_info()
---
drivers/phy/mediatek/phy-mtk-tphy.c | 162 ++++++++++++++++++++++++++++
1 file changed, 162 insertions(+)


Hello Chunfeng, thanks for the patch!
However, there are a few things to improve...

diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
index cdcef865fe9e..98a942c607a6 100644
--- a/drivers/phy/mediatek/phy-mtk-tphy.c
+++ b/drivers/phy/mediatek/phy-mtk-tphy.c
@@ -12,6 +12,7 @@
#include <linux/iopoll.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
@@ -41,6 +42,9 @@
#define SSUSB_SIFSLV_V2_U3PHYD 0x200
#define SSUSB_SIFSLV_V2_U3PHYA 0x400
+#define U3P_MISC_REG1 0x04
+#define MR1_EFUSE_AUTO_LOAD_DIS BIT(6)
+
#define U3P_USBPHYACR0 0x000
#define PA0_RG_U2PLL_FORCE_ON BIT(15)
#define PA0_USB20_PLL_PREDIV GENMASK(7, 6)
@@ -133,6 +137,8 @@
#define P3C_RG_SWRST_U3_PHYD_FORCE_EN BIT(24)
#define U3P_U3_PHYA_REG0 0x000
+#define P3A_RG_IEXT_INTR GENMASK(15, 10)
+#define P3A_RG_IEXT_INTR_VAL(x) ((0x3f & (x)) << 10)
#define P3A_RG_CLKDRV_OFF GENMASK(3, 2)
#define P3A_RG_CLKDRV_OFF_VAL(x) ((0x3 & (x)) << 2)
@@ -187,6 +193,19 @@
#define P3D_RG_FWAKE_TH GENMASK(21, 16)
#define P3D_RG_FWAKE_TH_VAL(x) ((0x3f & (x)) << 16)
+#define U3P_U3_PHYD_IMPCAL0 0x010
+#define P3D_RG_FORCE_TX_IMPEL BIT(31)
+#define P3D_RG_TX_IMPEL GENMASK(28, 24)
+#define P3D_RG_TX_IMPEL_VAL(x) ((0x1f & (x)) << 24)
+
+#define U3P_U3_PHYD_IMPCAL1 0x014
+#define P3D_RG_FORCE_RX_IMPEL BIT(31)
+#define P3D_RG_RX_IMPEL GENMASK(28, 24)
+#define P3D_RG_RX_IMPEL_VAL(x) ((0x1f & (x)) << 24)
+
+#define U3P_U3_PHYD_RSV 0x054
+#define P3D_RG_EFUSE_AUTO_LOAD_DIS BIT(12)
+
#define U3P_U3_PHYD_CDR1 0x05c
#define P3D_RG_CDR_BIR_LTD1 GENMASK(28, 24)
#define P3D_RG_CDR_BIR_LTD1_VAL(x) ((0x1f & (x)) << 24)
@@ -307,6 +326,11 @@ struct mtk_phy_pdata {
* 48M PLL, fix it by switching PLL to 26M from default 48M
*/
bool sw_pll_48m_to_26m;
+ /*
+ * Some SoCs (e.g. mt8195) drop a bit when use auto load efuse,
+ * support sw way, also support it for v2/v3 optionally.
+ */
+ bool sw_efuse_supported;
enum mtk_phy_version version;
};
@@ -336,6 +360,10 @@ struct mtk_phy_instance {
struct regmap *type_sw;
u32 type_sw_reg;
u32 type_sw_index;
+ u32 efuse_sw_en;
+ u32 efuse_intr;
+ u32 efuse_tx_imp;
+ u32 efuse_rx_imp;
int eye_src;
int eye_vrt;
int eye_term;
@@ -1040,6 +1068,130 @@ static int phy_type_set(struct mtk_phy_instance *instance)
return 0;
}
+static int phy_efuse_get(struct mtk_tphy *tphy, struct mtk_phy_instance *instance)
+{
+ struct device *dev = &instance->phy->dev;
+ int ret = 0;
+
+ /* tphy v1 doesn't support sw efuse, skip it */
+ if (!tphy->pdata->sw_efuse_supported) {
+ instance->efuse_sw_en = 0;
+ return 0;
+ }
+
+ /* software efuse is optional */
+ instance->efuse_sw_en = device_property_read_bool(dev, "nvmem-cells");
+ if (!instance->efuse_sw_en)
+ return 0;
+
+ switch (instance->type) {
+ case PHY_TYPE_USB2:
+ ret = nvmem_cell_read_variable_le_u32(dev, "intr", &instance->efuse_intr);
+ if (ret) {
+ dev_err(dev, "fail to get u2 intr efuse, %d\n", ret);
+ break;
+ }
+
+ /* no efuse, ignore it */
+ if (!instance->efuse_intr) {
+ dev_warn(dev, "no u2 intr efuse, but dts enable it\n");
+ instance->efuse_sw_en = 0;
+ break;
+ }
+
+ dev_dbg(dev, "u2 efuse - intr %x\n", instance->efuse_intr);
+ break;
+
+ case PHY_TYPE_USB3:
+ case PHY_TYPE_PCIE:
+ ret = nvmem_cell_read_variable_le_u32(dev, "intr", &instance->efuse_intr);
+ if (ret) {
+ dev_err(dev, "fail to get u3 intr efuse, %d\n", ret);
+ break;
+ }
+
+ ret = nvmem_cell_read_variable_le_u32(dev, "rx_imp", &instance->efuse_rx_imp);
+ if (ret) {
+ dev_err(dev, "fail to get u3 rx_imp efuse, %d\n", ret);
+ break;
+ }
+
+ ret = nvmem_cell_read_variable_le_u32(dev, "tx_imp", &instance->efuse_tx_imp);
+ if (ret) {
+ dev_err(dev, "fail to get u3 tx_imp efuse, %d\n", ret);
+ break;
+ }
+
+ /* no efuse, ignore it */
+ if (!instance->efuse_intr &&
+ !instance->efuse_rx_imp &&
+ !instance->efuse_rx_imp) {
+ dev_warn(dev, "no u3 intr efuse, but dts enable it\n");
+ instance->efuse_sw_en = 0;
+ break;
+ }
+
+ dev_dbg(dev, "u3 efuse - intr %x, rx_imp %x, tx_imp %x\n",
+ instance->efuse_intr, instance->efuse_rx_imp,instance->efuse_tx_imp);
+ break;
+ default:
+ dev_err(dev, "no sw efuse for type %d\n", instance->type);
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static void phy_efuse_set(struct mtk_phy_instance *instance)

The name for this function is a bit misleading and one may think that this
is writing efuses (aka blowing a fuse array), which doesn't look like being
the case at all.

What about changing it to phy_set_sw_efuse_params(), or something similar?


Thank you,
- Angelo