[PATCH v7 1/7] phy: add a driver for the Berlin SATA PHY
Sergei Shtylyov
sergei.shtylyov at cogentembedded.com
Wed Jun 25 12:03:25 PDT 2014
Hello.
On 06/23/2014 05:39 PM, Antoine Ténart wrote:
> The Berlin SoC has a two SATA ports. Add a PHY driver to handle them.
> The mode selection can let us think this PHY can be configured to fit
> other purposes. But there are reasons to think the SATA mode will be
> the only one usable: the PHY registers are only accessible indirectly
> through two registers in the SATA range, the PHY seems to be integrated
> and no information tells us the contrary. For these reasons, make the
> driver a SATA PHY driver.
I'm not even sure why you want to make it a separate driver if the
registers are mapped to SATA controller's range.
> Signed-off-by: Antoine Ténart <antoine.tenart at free-electrons.com>
[...]
> diff --git a/drivers/phy/phy-berlin-sata.c b/drivers/phy/phy-berlin-sata.c
> new file mode 100644
> index 000000000000..317f62358165
> --- /dev/null
> +++ b/drivers/phy/phy-berlin-sata.c
> @@ -0,0 +1,246 @@
[...]
+#define HOST_VSA_ADDR 0x0
+#define HOST_VSA_DATA 0x4
+#define PORT_VSR_ADDR 0x78
+#define PORT_VSR_DATA 0x7c
+#define PORT_SCR_CTL 0x2c
Could you keep this list sorted?
[...]
+struct phy_berlin_desc {
+ struct phy *phy;
+ u32 val;
Hm, aren't these power down bits? Why not call the field accordingly?
[...]
> +static int phy_berlin_sata_power_on(struct phy *phy)
> +{
> + struct phy_berlin_desc *desc = phy_get_drvdata(phy);
> + struct phy_berlin_priv *priv = to_berlin_sata_phy_priv(desc);
> + void __iomem *ctrl_reg = priv->base + 0x60 + (desc->index * 0x80);
> + int ret = 0;
> + u32 regval;
> +
> + clk_prepare_enable(priv->clk);
> +
> + spin_lock(&priv->lock);
> +
> + /* Power on PHY */
> + writel(CONTROL_REGISTER, priv->base + HOST_VSA_ADDR);
> + regval = readl(priv->base + HOST_VSA_DATA);
> + regval &= ~(desc->val);
Parens not needed here.
> + writel(regval, priv->base + HOST_VSA_DATA);
> +
> + /* Configure MBus */
> + writel(MBUS_SIZE_CONTROL, priv->base + HOST_VSA_ADDR);
> + regval = readl(priv->base + HOST_VSA_DATA);
> + regval |= MBUS_WRITE_REQUEST_SIZE_128 | MBUS_READ_REQUEST_SIZE_128;
> + writel(regval, priv->base + HOST_VSA_DATA);
It probably makes sense to factor these address/data register writes into
a separate function like phy_berlin_sata_reg_setbits().
[...]
> + /* set the controller speed */
> + writel(0x31, ctrl_reg + PORT_SCR_CTL);
Value undocumented? Or is this the SATA SControl register by chance?
[...]
> +static int phy_berlin_sata_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct phy *phy;
> + struct phy_provider *phy_provider;
> + struct phy_berlin_priv *priv;
> + struct resource *res;
> + int i;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -EINVAL;
> +
> + priv->base = devm_ioremap(dev, res->start, resource_size(res));
Can't you use devm_ioremap_resource()?
> + if (!priv->base)
> + return -ENOMEM;
> +
> + priv->clk = devm_clk_get(dev, NULL);
> + if (IS_ERR(priv->clk))
> + return PTR_ERR(priv->clk);
> +
> + dev_set_drvdata(dev, priv);
> + spin_lock_init(&priv->lock);
> +
> + for (i = 0; i < BERLIN_SATA_PHY_NB; i++) {
> + phy = devm_phy_create(dev, &phy_berlin_sata_ops, NULL);
> + if (IS_ERR(phy)) {
> + dev_err(dev, "failed to create PHY %d\n", i);
> + return PTR_ERR(phy);
> + }
> +
> + priv->phys[i].phy = phy;
> + priv->phys[i].val = phy_berlin_power_down_bits[i];
> + priv->phys[i].index = i;
> + phy_set_drvdata(phy, &priv->phys[i]);
> +
> + /* Make sure the PHY is off */
> + phy_berlin_sata_power_off(phy);
> + }
> +
> + phy_provider =
> + devm_of_phy_provider_register(dev, phy_berlin_sata_phy_xlate);
> + if (IS_ERR(phy_provider))
No dev_err() here?
> + return PTR_ERR(phy_provider);
> +
> + return 0;
> +}
WBR, Sergei
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