Re: [U-Boot] [PATCH v2 5/7] driver: net: ti: introduce common mdio support library

On Wed, Oct 31, 2018 at 2:10 PM Grygorii Strashko grygorii.strashko@ti.com wrote:

All existing TI SoCs network HW have similar MDIO implementation, so introduce common mdio support library which can be reused by TI networking drivers.

Reviewed-by: Tom Rini trini@konsulko.com Signed-off-by: Grygorii Strashko grygorii.strashko@ti.com

---

drivers/net/ti/Makefile | 2 +- drivers/net/ti/cpsw_mdio.c | 201 +++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ti/cpsw_mdio.h | 18 ++++ 3 files changed, 220 insertions(+), 1 deletion(-) create mode 100644 drivers/net/ti/cpsw_mdio.c create mode 100644 drivers/net/ti/cpsw_mdio.h

diff --git a/drivers/net/ti/Makefile b/drivers/net/ti/Makefile index 4ab4a27..d2b6f20 100644 --- a/drivers/net/ti/Makefile +++ b/drivers/net/ti/Makefile @@ -2,6 +2,6 @@ # # Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/

-obj-$(CONFIG_DRIVER_TI_CPSW) += cpsw.o cpsw-common.o +obj-$(CONFIG_DRIVER_TI_CPSW) += cpsw.o cpsw-common.o cpsw_mdio.o obj-$(CONFIG_DRIVER_TI_EMAC) += davinci_emac.o obj-$(CONFIG_DRIVER_TI_KEYSTONE_NET) += keystone_net.o diff --git a/drivers/net/ti/cpsw_mdio.c b/drivers/net/ti/cpsw_mdio.c new file mode 100644 index 0000000..f4211b7 --- /dev/null +++ b/drivers/net/ti/cpsw_mdio.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • CPSW MDIO generic driver for TI AMxx/K2x/EMAC devices.
• • Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
• */

+#include <common.h> +#include <asm/io.h> +#include <miiphy.h> +#include <wait_bit.h>

+struct cpsw_mdio_regs {

•   u32     version;
  

•   u32     control;
  

+#define CONTROL_IDLE BIT(31) +#define CONTROL_ENABLE BIT(30) +#define CONTROL_FAULT BIT(19) +#define CONTROL_FAULT_ENABLE BIT(18) +#define CONTROL_DIV_MASK GENMASK(15, 0)

•   u32     alive;
  

•   u32     link;
  

•   u32     linkintraw;
  

•   u32     linkintmasked;
  

•   u32     __reserved_0[2];
  

•   u32     userintraw;
  

•   u32     userintmasked;
  

•   u32     userintmaskset;
  

•   u32     userintmaskclr;
  

•   u32     __reserved_1[20];
  

•   struct {
  

•           u32             access;
  

•           u32             physel;
  

+#define USERACCESS_GO BIT(31) +#define USERACCESS_WRITE BIT(30) +#define USERACCESS_ACK BIT(29) +#define USERACCESS_READ (0) +#define USERACCESS_PHY_REG_SHIFT (21) +#define USERACCESS_PHY_ADDR_SHIFT (16) +#define USERACCESS_DATA GENMASK(15, 0)

•   } user[0];
  

+};

+#define CPSW_MDIO_DIV_DEF 0xff +#define PHY_REG_MASK 0x1f +#define PHY_ID_MASK 0x1f

+/*

• • This timeout definition is a worst-case ultra defensive measure against
• • unexpected controller lock ups. Ideally, we should never ever hit this
• • scenario in practice.
• */

+#define CPSW_MDIO_TIMEOUT 100 /* msecs */

+struct cpsw_mdio {

•   struct cpsw_mdio_regs *regs;
  

•   struct mii_dev *bus;
  

•   int div;
  

+};

+/* wait until hardware is ready for another user access */ +static inline u32 cpsw_mdio_wait_for_user_access(struct cpsw_mdio *mdio)

You should be returning an int

+{

•   int ret;
  

•   ret = wait_for_bit_le32(&mdio->regs->user[0].access,
  

•                           USERACCESS_GO, false, CPSW_MDIO_TIMEOUT, false);
  

•   if (ret)
  

•           return ret;
  

•   return readl(&mdio->regs->user[0].access);
  

This doesn't make sense as written. You should return an error, not a register value.

+}

+static int cpsw_mdio_read(struct mii_dev *bus, int phy_id,

•                     int dev_addr, int phy_reg)
  

+{

•   struct cpsw_mdio *mdio = bus->priv;
  

•   int data;
  

•   u32 reg;
  

•   if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
  

•           return -EINVAL;
  

•   cpsw_mdio_wait_for_user_access(mdio);
  

You should return any error that this returns.

•   reg = (USERACCESS_GO | USERACCESS_READ |
  

•          (phy_reg << USERACCESS_PHY_REG_SHIFT) |
  

•          (phy_id << USERACCESS_PHY_ADDR_SHIFT));
  

•   writel(reg, &mdio->regs->user[0].access);
  

•   reg = cpsw_mdio_wait_for_user_access(mdio);
  

You should return any error that this returns.

If you need to read this register, then do it here, not inside the wait function.

•   data = (reg & USERACCESS_ACK) ? (reg & USERACCESS_DATA) : -1;
  

•   return data;
  

+}

+static int cpsw_mdio_write(struct mii_dev *bus, int phy_id, int dev_addr,

•                      int phy_reg, u16 data)
  

+{

•   struct cpsw_mdio *mdio = bus->priv;
  

•   u32 reg;
  

•   if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
  

•           return -EINVAL;
  

•   cpsw_mdio_wait_for_user_access(mdio);
  

You should return any error that this returns.

•   reg = (USERACCESS_GO | USERACCESS_WRITE |
  

•          (phy_reg << USERACCESS_PHY_REG_SHIFT) |
  

•          (phy_id << USERACCESS_PHY_ADDR_SHIFT) |
  

•          (data & USERACCESS_DATA));
  

•   writel(reg, &mdio->regs->user[0].access);
  

•   cpsw_mdio_wait_for_user_access(mdio);
  

You should return any error that this returns.

•   return 0;
  

+}

+u32 cpsw_mdio_get_alive(struct mii_dev *bus) +{

•   struct cpsw_mdio *mdio = bus->priv;
  

•   u32 val;
  

•   val = readl(&mdio->regs->control);
  

•   return val & GENMASK(15, 0);
  

+}

+struct mii_dev *cpsw_mdio_init(const char *name, u32 mdio_base,

•                          u32 bus_freq, int fck_freq)
  

+{

•   struct cpsw_mdio *cpsw_mdio;
  

•   int ret;
  

•   cpsw_mdio = calloc(1, sizeof(*cpsw_mdio));
  

•   if (!cpsw_mdio) {
  

•           debug("failed to alloc cpsw_mdio\n");
  

•           return NULL;
  

•   }
  

•   cpsw_mdio->bus = mdio_alloc();
  

•   if (!cpsw_mdio->bus) {
  

•           debug("failed to alloc mii bus\n");
  

•           free(cpsw_mdio);
  

•           return NULL;
  

•   }
  

•   cpsw_mdio->regs = (struct cpsw_mdio_regs *)mdio_base;
  

•   if (!bus_freq || !fck_freq)
  

•           cpsw_mdio->div = CPSW_MDIO_DIV_DEF;
  

•   else
  

•           cpsw_mdio->div = (fck_freq / bus_freq) - 1;
  

•   cpsw_mdio->div &= CONTROL_DIV_MASK;
  

•   /* set enable and clock divider */
  

•   writel(cpsw_mdio->div | CONTROL_ENABLE | CONTROL_FAULT |
  

•          CONTROL_FAULT_ENABLE, &cpsw_mdio->regs->control);
  

•   wait_for_bit_le32(&cpsw_mdio->regs->control,
  

•                     CONTROL_IDLE, false, CPSW_MDIO_TIMEOUT, true);
  

•   /*
  

•    * wait for scan logic to settle:
  

•    * the scan time consists of (a) a large fixed component, and (b) a
  

•    * small component that varies with the mii bus frequency.  These
  

•    * were estimated using measurements at 1.1 and 2.2 MHz on tnetv107x
  

•    * silicon.  Since the effect of (b) was found to be largely
  

•    * negligible, we keep things simple here.
  

•    */
  

•   mdelay(1);
  

•   cpsw_mdio->bus->read = cpsw_mdio_read;
  

•   cpsw_mdio->bus->write = cpsw_mdio_write;
  

•   cpsw_mdio->bus->priv = cpsw_mdio;
  

•   snprintf(cpsw_mdio->bus->name, sizeof(cpsw_mdio->bus->name), name);
  

•   ret = mdio_register(cpsw_mdio->bus);
  

•   if (ret < 0) {
  

•           debug("failed to register mii bus\n");
  

•           goto free_bus;
  

•   }
  

•   return cpsw_mdio->bus;
  

+free_bus:

•   mdio_free(cpsw_mdio->bus);
  

•   free(cpsw_mdio);
  

•   return NULL;
  

+}

+void cpsw_mdio_free(struct mii_dev *bus) +{

•   struct cpsw_mdio *mdio = bus->priv;
  

•   u32 reg;
  

•   /* disable mdio */
  

•   reg = readl(&mdio->regs->control);
  

•   reg &= ~CONTROL_ENABLE;
  

•   writel(reg, &mdio->regs->control);
  

•   mdio_unregister(bus);
  

•   mdio_free(bus);
  

•   free(mdio);
  

+} diff --git a/drivers/net/ti/cpsw_mdio.h b/drivers/net/ti/cpsw_mdio.h new file mode 100644 index 0000000..4a76d4e --- /dev/null +++ b/drivers/net/ti/cpsw_mdio.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*

• • CPSW MDIO generic driver API for TI AMxx/K2x/EMAC devices.
• • Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
• */

+#ifndef CPSW_MDIO_H_ +#define CPSW_MDIO_H_

+struct cpsw_mdio;

+struct mii_dev *cpsw_mdio_init(const char *name, u32 mdio_base,

•                          u32 bus_freq, int fck_freq);
  

+void cpsw_mdio_free(struct mii_dev *bus); +u32 cpsw_mdio_get_alive(struct mii_dev *bus);

+#endif /* CPSW_MDIO_H_ */

2.10.5

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