On 16/08/2023 08:38, Sriranjani P wrote:
>
>
>> -----Original Message-----
>> From: Krzysztof Kozlowski [mailto:krzysztof.kozlowski@linaro.org]
>> Sent: 15 August 2023 01:21
>> To: Sriranjani P <sriranjani.p@samsung.com>; davem@davemloft.net;
>> edumazet@google.com; kuba@kernel.org; pabeni@redhat.com;
>> robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org;
>> conor+dt@kernel.org; richardcochran@gmail.com;
>> alexandre.torgue@foss.st.com; joabreu@synopsys.com;
>> mcoquelin.stm32@gmail.com; alim.akhtar@samsung.com; linux-
>> fsd@tesla.com; pankaj.dubey@samsung.com; swathi.ks@samsung.com;
>> ravi.patel@samsung.com
>> Cc: netdev@vger.kernel.org; devicetree@vger.kernel.org; linux-
>> kernel@vger.kernel.org; linux-samsung-soc@vger.kernel.org; linux-arm-
>> kernel@lists.infradead.org; Chandrasekar R <rcsekar@samsung.com>;
>> Suresh Siddha <ssiddha@tesla.com>
>> Subject: Re: [PATCH v3 2/4] net: stmmac: dwc-qos: Add FSD EQoS support
>>
>> On 14/08/2023 13:25, Sriranjani P wrote:
>>> The FSD SoC contains two instance of the Synopsys DWC ethernet QOS IP
>> core.
>>> The binding that it uses is slightly different from existing ones
>>> because of the integration (clocks, resets).
>>>
>>> For FSD SoC, a mux switch is needed between internal and external clocks.
>>> By default after reset internal clock is used but for receiving
>>> packets properly, external clock is needed. Mux switch to external
>>> clock happens only when the external clock is present.
>>>
>>> Signed-off-by: Chandrasekar R <rcsekar@samsung.com>
>>> Signed-off-by: Suresh Siddha <ssiddha@tesla.com>
>>> Signed-off-by: Swathi K S <swathi.ks@samsung.com>
>>> Signed-off-by: Sriranjani P <sriranjani.p@samsung.com>
>>> ---
>>
>>
>>> +static int dwc_eqos_setup_rxclock(struct platform_device *pdev, int
>>> +ins_num) {
>>> + struct device_node *np = pdev->dev.of_node;
>>> + struct regmap *syscon;
>>> + unsigned int reg;
>>> +
>>> + if (np && of_property_read_bool(np, "fsd-rx-clock-skew")) {
>>> + syscon = syscon_regmap_lookup_by_phandle_args(np,
>>> + "fsd-rx-clock-
>> skew",
>>> + 1, ®);
>>> + if (IS_ERR(syscon)) {
>>> + dev_err(&pdev->dev,
>>> + "couldn't get the rx-clock-skew syscon!\n");
>>> + return PTR_ERR(syscon);
>>> + }
>>> +
>>> + regmap_write(syscon, reg, rx_clock_skew_val[ins_num]);
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int fsd_eqos_clk_init(struct fsd_eqos_plat_data *plat,
>>> + struct plat_stmmacenet_data *data) {
>>> + int ret = 0, i;
>>> +
>>> + const struct fsd_eqos_variant *fsd_eqos_v_data =
>>> + plat->fsd_eqos_inst_var;
>>> +
>>> + plat->clks = devm_kcalloc(plat->dev, fsd_eqos_v_data->num_clks,
>>> + sizeof(*plat->clks), GFP_KERNEL);
>>> + if (!plat->clks)
>>> + return -ENOMEM;
>>> +
>>> + for (i = 0; i < fsd_eqos_v_data->num_clks; i++)
>>> + plat->clks[i].id = fsd_eqos_v_data->clk_list[i];
>>> +
>>> + ret = devm_clk_bulk_get(plat->dev, fsd_eqos_v_data->num_clks,
>>> + plat->clks);
>>
>> Instead of duplicating entire clock management with existing code, you
>> should extend/rework existing one.
>>
>> This code is unfortunately great example how not to stuff vendor code into
>> upstream project. :(
>
> I will check again if I can extend existing one to support FSD platform specific requirement.
>
>>
>>> +
>>> + return ret;
>>> +}
>>> +
>>> +static int fsd_clks_endisable(void *priv, bool enabled) {
>>> + int ret, num_clks;
>>> + struct fsd_eqos_plat_data *plat = priv;
>>> +
>>> + num_clks = plat->fsd_eqos_inst_var->num_clks;
>>> +
>>> + if (enabled) {
>>> + ret = clk_bulk_prepare_enable(num_clks, plat->clks);
>>> + if (ret) {
>>> + dev_err(plat->dev, "Clock enable failed, err = %d\n",
>> ret);
>>> + return ret;
>>> + }
>>> + } else {
>>> + clk_bulk_disable_unprepare(num_clks, plat->clks);
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int fsd_eqos_probe(struct platform_device *pdev,
>>> + struct plat_stmmacenet_data *data,
>>> + struct stmmac_resources *res)
>>> +{
>>> + struct fsd_eqos_plat_data *priv_plat;
>>> + struct device_node *np = pdev->dev.of_node;
>>> + int ret = 0;
>>> +
>>> + priv_plat = devm_kzalloc(&pdev->dev, sizeof(*priv_plat),
>> GFP_KERNEL);
>>> + if (!priv_plat) {
>>> + ret = -ENOMEM;
>>
>> return -ENOMEM
>
> Will fix this in v4.
>
>>
>>> + goto error;
>>> + }
>>> +
>>> + priv_plat->dev = &pdev->dev;
>>> + data->bus_id = of_alias_get_id(np, "eth");
>>
>> No, you cannot do like this. Aliases are board specific and are based on
>> labeling on the board.
>
> So if I understood this correctly, I need to move alias in the board specific DTS file
This part: yes
> and I can use this, because we have to handle rx-clock-skew differently for the two instances in the FSD platform.
Not really. Do you expect it to work correctly if given EQoS instance
receives different alias, e.g. 5?
> Another approach we took in v1, by specifying the value to be programmed in rx-clock-skew property itself, but it seems it is not a preferred approach.
> I can see that in drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c +436 common code is already using this API and getting alias id, so I can probably use the same rather getting same again here, but I have to specify alias in DTS file.
Getting alias ID is okay in general. It is used to provide user-visible
ID of the devices (see mmc). Using such alias to configure hardware is
abuse of the alias, because of the reasons I said - how is it supposed
to work if alias is 5 (this is perfectly valid alias)?
I suspect that all this is to substitute missing abstractions, like
clocks, phys or resets...
Best regards,
Krzysztof
@@ -20,6 +20,7 @@
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/stmmac.h>
+#include <linux/regmap.h>
#include "stmmac_platform.h"
#include "dwmac4.h"
@@ -37,6 +38,45 @@ struct tegra_eqos {
struct gpio_desc *reset;
};
+enum fsd_rxmux_clk {
+ FSD_RXCLK_MUX = 7,
+ FSD_RXCLK_EXTERNAL,
+ FSD_RXCLK_INTERNAL
+};
+
+struct fsd_eqos_plat_data {
+ const struct fsd_eqos_variant *fsd_eqos_inst_var;
+ struct clk_bulk_data *clks;
+ struct device *dev;
+};
+
+struct fsd_eqos_variant {
+ const char * const *clk_list;
+ int num_clks;
+};
+
+static const char * const fsd_eqos_instance_0_clk[] = {
+ "ptp_ref", "master_bus", "slave_bus", "tx", "rx"
+};
+
+static const char * const fsd_eqos_instance_1_clk[] = {
+ "ptp_ref", "master_bus", "slave_bus", "tx", "rx", "master2_bus",
+ "slave2_bus", "eqos_rxclk_mux", "eqos_phyrxclk", "dout_peric_rgmii_clk"
+};
+
+static const int rx_clock_skew_val[] = {0x2, 0x0};
+
+static const struct fsd_eqos_variant fsd_eqos_clk_info[] = {
+ {
+ .clk_list = fsd_eqos_instance_0_clk,
+ .num_clks = ARRAY_SIZE(fsd_eqos_instance_0_clk)
+ },
+ {
+ .clk_list = fsd_eqos_instance_1_clk,
+ .num_clks = ARRAY_SIZE(fsd_eqos_instance_1_clk)
+ },
+};
+
static int dwc_eth_dwmac_config_dt(struct platform_device *pdev,
struct plat_stmmacenet_data *plat_dat)
{
@@ -265,6 +305,132 @@ static int tegra_eqos_init(struct platform_device *pdev, void *priv)
return 0;
}
+static int dwc_eqos_rxmux_setup(void *priv, bool external)
+{
+ struct fsd_eqos_plat_data *plat = priv;
+
+ /* doesn't support RX clock mux */
+ if (!plat->clks[FSD_RXCLK_MUX].clk)
+ return 0;
+
+ if (external)
+ return clk_set_parent(plat->clks[FSD_RXCLK_MUX].clk,
+ plat->clks[FSD_RXCLK_EXTERNAL].clk);
+ else
+ return clk_set_parent(plat->clks[FSD_RXCLK_MUX].clk,
+ plat->clks[FSD_RXCLK_INTERNAL].clk);
+}
+
+static int dwc_eqos_setup_rxclock(struct platform_device *pdev, int ins_num)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct regmap *syscon;
+ unsigned int reg;
+
+ if (np && of_property_read_bool(np, "fsd-rx-clock-skew")) {
+ syscon = syscon_regmap_lookup_by_phandle_args(np,
+ "fsd-rx-clock-skew",
+ 1, ®);
+ if (IS_ERR(syscon)) {
+ dev_err(&pdev->dev,
+ "couldn't get the rx-clock-skew syscon!\n");
+ return PTR_ERR(syscon);
+ }
+
+ regmap_write(syscon, reg, rx_clock_skew_val[ins_num]);
+ }
+
+ return 0;
+}
+
+static int fsd_eqos_clk_init(struct fsd_eqos_plat_data *plat,
+ struct plat_stmmacenet_data *data)
+{
+ int ret = 0, i;
+
+ const struct fsd_eqos_variant *fsd_eqos_v_data =
+ plat->fsd_eqos_inst_var;
+
+ plat->clks = devm_kcalloc(plat->dev, fsd_eqos_v_data->num_clks,
+ sizeof(*plat->clks), GFP_KERNEL);
+ if (!plat->clks)
+ return -ENOMEM;
+
+ for (i = 0; i < fsd_eqos_v_data->num_clks; i++)
+ plat->clks[i].id = fsd_eqos_v_data->clk_list[i];
+
+ ret = devm_clk_bulk_get(plat->dev, fsd_eqos_v_data->num_clks,
+ plat->clks);
+
+ return ret;
+}
+
+static int fsd_clks_endisable(void *priv, bool enabled)
+{
+ int ret, num_clks;
+ struct fsd_eqos_plat_data *plat = priv;
+
+ num_clks = plat->fsd_eqos_inst_var->num_clks;
+
+ if (enabled) {
+ ret = clk_bulk_prepare_enable(num_clks, plat->clks);
+ if (ret) {
+ dev_err(plat->dev, "Clock enable failed, err = %d\n", ret);
+ return ret;
+ }
+ } else {
+ clk_bulk_disable_unprepare(num_clks, plat->clks);
+ }
+
+ return 0;
+}
+
+static int fsd_eqos_probe(struct platform_device *pdev,
+ struct plat_stmmacenet_data *data,
+ struct stmmac_resources *res)
+{
+ struct fsd_eqos_plat_data *priv_plat;
+ struct device_node *np = pdev->dev.of_node;
+ int ret = 0;
+
+ priv_plat = devm_kzalloc(&pdev->dev, sizeof(*priv_plat), GFP_KERNEL);
+ if (!priv_plat) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ priv_plat->dev = &pdev->dev;
+ data->bus_id = of_alias_get_id(np, "eth");
+
+ priv_plat->fsd_eqos_inst_var = &fsd_eqos_clk_info[data->bus_id];
+
+ ret = fsd_eqos_clk_init(priv_plat, data);
+
+ data->bsp_priv = priv_plat;
+ data->clks_config = fsd_clks_endisable;
+ data->rxmux_setup = dwc_eqos_rxmux_setup;
+
+ ret = fsd_clks_endisable(priv_plat, true);
+ if (ret)
+ goto error;
+
+ ret = dwc_eqos_setup_rxclock(pdev, data->bus_id);
+ if (ret) {
+ fsd_clks_endisable(priv_plat, false);
+ dev_err_probe(&pdev->dev, ret, "Unable to setup rxclock\n");
+ }
+
+error:
+ return ret;
+}
+
+static void fsd_eqos_remove(struct platform_device *pdev)
+{
+ struct fsd_eqos_plat_data *priv_plat = get_stmmac_bsp_priv(&pdev->dev);
+
+ fsd_clks_endisable(priv_plat, false);
+}
+
static int tegra_eqos_probe(struct platform_device *pdev,
struct plat_stmmacenet_data *data,
struct stmmac_resources *res)
@@ -411,6 +577,11 @@ static const struct dwc_eth_dwmac_data tegra_eqos_data = {
.remove = tegra_eqos_remove,
};
+static const struct dwc_eth_dwmac_data fsd_eqos_data = {
+ .probe = fsd_eqos_probe,
+ .remove = fsd_eqos_remove,
+};
+
static int dwc_eth_dwmac_probe(struct platform_device *pdev)
{
const struct dwc_eth_dwmac_data *data;
@@ -482,6 +653,7 @@ static void dwc_eth_dwmac_remove(struct platform_device *pdev)
static const struct of_device_id dwc_eth_dwmac_match[] = {
{ .compatible = "snps,dwc-qos-ethernet-4.10", .data = &dwc_qos_data },
{ .compatible = "nvidia,tegra186-eqos", .data = &tegra_eqos_data },
+ { .compatible = "tesla,dwc-qos-ethernet-4.21", .data = &fsd_eqos_data },
{ }
};
MODULE_DEVICE_TABLE(of, dwc_eth_dwmac_match);
@@ -3883,6 +3883,12 @@ static int __stmmac_open(struct net_device *dev,
netif_tx_start_all_queues(priv->dev);
stmmac_enable_all_dma_irq(priv);
+ if (priv->plat->rxmux_setup) {
+ ret = priv->plat->rxmux_setup(priv->plat->bsp_priv, true);
+ if (ret)
+ netdev_err(priv->dev, "Rxmux setup failed\n");
+ }
+
return 0;
irq_error:
@@ -3936,7 +3942,13 @@ static void stmmac_fpe_stop_wq(struct stmmac_priv *priv)
static int stmmac_release(struct net_device *dev)
{
struct stmmac_priv *priv = netdev_priv(dev);
- u32 chan;
+ u32 chan, ret;
+
+ if (priv->plat->rxmux_setup) {
+ ret = priv->plat->rxmux_setup(priv->plat->bsp_priv, false);
+ if (ret)
+ netdev_err(priv->dev, "Rxmux setup failed\n");
+ }
if (device_may_wakeup(priv->device))
phylink_speed_down(priv->phylink, false);
@@ -7630,11 +7642,17 @@ int stmmac_suspend(struct device *dev)
{
struct net_device *ndev = dev_get_drvdata(dev);
struct stmmac_priv *priv = netdev_priv(ndev);
- u32 chan;
+ u32 chan, ret;
if (!ndev || !netif_running(ndev))
return 0;
+ if (priv->plat->rxmux_setup) {
+ ret = priv->plat->rxmux_setup(priv->plat->bsp_priv, false);
+ if (ret)
+ netdev_err(priv->dev, "Rxmux setup failed\n");
+ }
+
mutex_lock(&priv->lock);
netif_device_detach(ndev);
@@ -7799,6 +7817,12 @@ int stmmac_resume(struct device *dev)
mutex_unlock(&priv->lock);
rtnl_unlock();
+ if (priv->plat->rxmux_setup) {
+ ret = priv->plat->rxmux_setup(priv->plat->bsp_priv, true);
+ if (ret)
+ netdev_err(priv->dev, "Rxmux setup failed\n");
+ }
+
netif_device_attach(ndev);
return 0;
@@ -264,6 +264,7 @@ struct plat_stmmacenet_data {
void (*ptp_clk_freq_config)(struct stmmac_priv *priv);
int (*init)(struct platform_device *pdev, void *priv);
void (*exit)(struct platform_device *pdev, void *priv);
+ int (*rxmux_setup)(void *priv, bool external);
struct mac_device_info *(*setup)(void *priv);
int (*clks_config)(void *priv, bool enabled);
int (*crosststamp)(ktime_t *device, struct system_counterval_t *system,