[PATCH v5 18/18] PCI: dwc: artpec6: Add support for the ARTPEC-7 SoC

Niklas Cassel
2017-11-20T13:34:14Z

Add support for the ARTPEC-7 SoC in the artpec6 driver.
The ARTPEC-6 SoC and the ARTPEC-7 SoC are very similar.
Unfortunately, some fields in the PCIECFG and PCIESTAT
register have changed.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
---
drivers/pci/dwc/pcie-artpec6.c | 187 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 183 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/dwc/pcie-artpec6.c b/drivers/pci/dwc/pcie-artpec6.c
index 064c5a93ea80..312f21b6e013 100644
--- a/drivers/pci/dwc/pcie-artpec6.c
+++ b/drivers/pci/dwc/pcie-artpec6.c
@@ -27,14 +27,21 @@

#define to_artpec6_pcie(x) dev_get_drvdata((x)->dev)

+enum artpec_pcie_variants {
+ ARTPEC6,
+ ARTPEC7,
+};
+
struct artpec6_pcie {
struct dw_pcie *pci;
struct regmap *regmap; /* DT axis,syscon-pcie */
void __iomem *phy_base; /* DT phy */
+ enum artpec_pcie_variants variant;
enum dw_pcie_device_mode mode;
};

struct artpec_pcie_of_data {
+ enum artpec_pcie_variants variant;
enum dw_pcie_device_mode mode;
};

@@ -43,6 +50,13 @@ static const struct of_device_id artpec6_pcie_of_match[];
/* PCIe Port Logic registers (memory-mapped) */
#define PL_OFFSET 0x700

+#define ACK_F_ASPM_CTRL_OFF (PL_OFFSET + 0xc)
+#define ACK_N_FTS_MASK GENMASK(15, 8)
+#define ACK_N_FTS(x) (((x) << 8) & ACK_N_FTS_MASK)
+
+#define FAST_TRAINING_SEQ_MASK GENMASK(7, 0)
+#define FAST_TRAINING_SEQ(x) (((x) << 0) & FAST_TRAINING_SEQ_MASK)
+
/* ARTPEC-6 specific registers */
#define PCIECFG 0x18
#define PCIECFG_DBG_OEN BIT(24)
@@ -57,6 +71,13 @@ static const struct of_device_id artpec6_pcie_of_match[];
#define PCIECFG_MODE_TX_DRV_EN BIT(3)
#define PCIECFG_CISRREN BIT(2)
#define PCIECFG_MACRO_ENABLE BIT(0)
+/* ARTPEC-7 specific fields */
+#define PCIECFG_REFCLKSEL BIT(23)
+#define PCIECFG_NOC_RESET BIT(3)
+
+#define PCIESTAT 0x1c
+/* ARTPEC-7 specific fields */
+#define PCIESTAT_EXTREFCLK BIT(3)

#define NOCCFG 0x40
#define NOCCFG_ENABLE_CLK_PCIE BIT(4)
@@ -67,6 +88,12 @@ static const struct of_device_id artpec6_pcie_of_match[];
#define PHY_STATUS 0x118
#define PHY_COSPLLLOCK BIT(0)

+#define PHY_TX_ASIC_OUT 0x4040
+#define PHY_TX_ASIC_OUT_TX_ACK BIT(0)
+
+#define PHY_RX_ASIC_OUT 0x405c
+#define PHY_RX_ASIC_OUT_ACK BIT(0)
+
static u32 artpec6_pcie_readl(struct artpec6_pcie *artpec6_pcie, u32 offset)
{
u32 val;
@@ -125,7 +152,7 @@ static const struct dw_pcie_ops dw_pcie_ops = {
.stop_link = artpec6_pcie_stop_link,
};

-static void artpec6_pcie_wait_for_phy(struct artpec6_pcie *artpec6_pcie)
+static void artpec6_pcie_wait_for_phy_a6(struct artpec6_pcie *artpec6_pcie)
{
struct dw_pcie *pci = artpec6_pcie->pci;
struct device *dev = pci->dev;
@@ -152,7 +179,49 @@ static void artpec6_pcie_wait_for_phy(struct artpec6_pcie *artpec6_pcie)
dev_err(dev, "PHY PLL did not lock\n");
}

-static void artpec6_pcie_init_phy(struct artpec6_pcie *artpec6_pcie)
+static void artpec6_pcie_wait_for_phy_a7(struct artpec6_pcie *artpec6_pcie)
+{
+ struct dw_pcie *pci = artpec6_pcie->pci;
+ struct device *dev = pci->dev;
+ u32 val;
+ u16 phy_status_tx, phy_status_rx;
+ unsigned int retries;
+
+ retries = 50;
+ do {
+ usleep_range(1000, 2000);
+ val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+ retries--;
+ } while (retries &&
+ (val & (NOCCFG_POWER_PCIE_IDLEACK | NOCCFG_POWER_PCIE_IDLE)));
+ if (!retries)
+ dev_err(dev, "PCIe clock manager did not leave idle state\n");
+
+ retries = 50;
+ do {
+ usleep_range(1000, 2000);
+ phy_status_tx = readw(artpec6_pcie->phy_base + PHY_TX_ASIC_OUT);
+ phy_status_rx = readw(artpec6_pcie->phy_base + PHY_RX_ASIC_OUT);
+ retries--;
+ } while (retries && ((phy_status_tx & PHY_TX_ASIC_OUT_TX_ACK) ||
+ (phy_status_rx & PHY_RX_ASIC_OUT_ACK)));
+ if (!retries)
+ dev_err(dev, "PHY did not enter Pn state\n");
+}
+
+static void artpec6_pcie_wait_for_phy(struct artpec6_pcie *artpec6_pcie)
+{
+ switch (artpec6_pcie->variant) {
+ case ARTPEC6:
+ artpec6_pcie_wait_for_phy_a6(artpec6_pcie);
+ break;
+ case ARTPEC7:
+ artpec6_pcie_wait_for_phy_a7(artpec6_pcie);
+ break;
+ }
+}
+
+static void artpec6_pcie_init_phy_a6(struct artpec6_pcie *artpec6_pcie)
{
u32 val;

@@ -182,12 +251,90 @@ static void artpec6_pcie_init_phy(struct artpec6_pcie *artpec6_pcie)
artpec6_pcie_writel(artpec6_pcie, NOCCFG, val);
}

+static void artpec6_pcie_init_phy_a7(struct artpec6_pcie *artpec6_pcie)
+{
+ struct dw_pcie *pci = artpec6_pcie->pci;
+ u32 val;
+ bool extrefclk;
+
+ /* Check if external reference clock is connected */
+ val = artpec6_pcie_readl(artpec6_pcie, PCIESTAT);
+ extrefclk = !!(val & PCIESTAT_EXTREFCLK);
+ dev_dbg(pci->dev, "Using reference clock: %s\n",
+ extrefclk ? "external" : "internal");
+
+ val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+ val |= PCIECFG_RISRCREN | /* Receiver term. 50 Ohm */
+ PCIECFG_PCLK_ENABLE;
+ if (extrefclk)
+ val |= PCIECFG_REFCLKSEL;
+ else
+ val &= ~PCIECFG_REFCLKSEL;
+ artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+ usleep_range(10, 20);
+
+ val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+ val |= NOCCFG_ENABLE_CLK_PCIE;
+ artpec6_pcie_writel(artpec6_pcie, NOCCFG, val);
+ usleep_range(20, 30);
+
+ val = artpec6_pcie_readl(artpec6_pcie, NOCCFG);
+ val &= ~NOCCFG_POWER_PCIE_IDLEREQ;
+ artpec6_pcie_writel(artpec6_pcie, NOCCFG, val);
+}
+
+static void artpec6_pcie_init_phy(struct artpec6_pcie *artpec6_pcie)
+{
+ switch (artpec6_pcie->variant) {
+ case ARTPEC6:
+ artpec6_pcie_init_phy_a6(artpec6_pcie);
+ break;
+ case ARTPEC7:
+ artpec6_pcie_init_phy_a7(artpec6_pcie);
+ break;
+ }
+}
+
+static void artpec6_pcie_set_nfts(struct artpec6_pcie *artpec6_pcie)
+{
+ struct dw_pcie *pci = artpec6_pcie->pci;
+ u32 val;
+
+ if (artpec6_pcie->variant != ARTPEC7)
+ return;
+
+ /*
+ * Increase the N_FTS (Number of Fast Training Sequences)
+ * to be transmitted when transitioning from L0s to L0.
+ */
+ val = dw_pcie_readl_dbi(pci, ACK_F_ASPM_CTRL_OFF);
+ val &= ~ACK_N_FTS_MASK;
+ val |= ACK_N_FTS(180);
+ dw_pcie_writel_dbi(pci, ACK_F_ASPM_CTRL_OFF, val);
+
+ /*
+ * Set the Number of Fast Training Sequences that the core
+ * advertises as its N_FTS during Gen2 or Gen3 link training.
+ */
+ val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+ val &= ~FAST_TRAINING_SEQ_MASK;
+ val |= FAST_TRAINING_SEQ(180);
+ dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
+}
+
static void artpec6_pcie_assert_core_reset(struct artpec6_pcie *artpec6_pcie)
{
u32 val;

val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
- val |= PCIECFG_CORE_RESET_REQ;
+ switch (artpec6_pcie->variant) {
+ case ARTPEC6:
+ val |= PCIECFG_CORE_RESET_REQ;
+ break;
+ case ARTPEC7:
+ val &= ~PCIECFG_NOC_RESET;
+ break;
+ }
artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
}

@@ -196,7 +343,14 @@ static void artpec6_pcie_deassert_core_reset(struct artpec6_pcie *artpec6_pcie)
u32 val;

val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
- val &= ~PCIECFG_CORE_RESET_REQ;
+ switch (artpec6_pcie->variant) {
+ case ARTPEC6:
+ val &= ~PCIECFG_CORE_RESET_REQ;
+ break;
+ case ARTPEC7:
+ val |= PCIECFG_NOC_RESET;
+ break;
+ }
artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
usleep_range(100, 200);
}
@@ -219,6 +373,7 @@ static int artpec6_pcie_host_init(struct pcie_port *pp)
artpec6_pcie_init_phy(artpec6_pcie);
artpec6_pcie_deassert_core_reset(artpec6_pcie);
artpec6_pcie_wait_for_phy(artpec6_pcie);
+ artpec6_pcie_set_nfts(artpec6_pcie);
dw_pcie_setup_rc(pp);
artpec6_pcie_establish_link(pci);
dw_pcie_wait_for_link(pci);
@@ -287,6 +442,7 @@ static void artpec6_pcie_ep_init(struct dw_pcie_ep *ep)
artpec6_pcie_init_phy(artpec6_pcie);
artpec6_pcie_deassert_core_reset(artpec6_pcie);
artpec6_pcie_wait_for_phy(artpec6_pcie);
+ artpec6_pcie_set_nfts(artpec6_pcie);

for (bar = BAR_0; bar <= BAR_5; bar++)
dw_pcie_ep_reset_bar(pci, bar);
@@ -358,6 +514,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
int ret;
const struct of_device_id *match;
const struct artpec_pcie_of_data *data;
+ enum artpec_pcie_variants variant;
enum dw_pcie_device_mode mode;

match = of_match_device(artpec6_pcie_of_match, dev);
@@ -365,6 +522,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
return -EINVAL;

data = (struct artpec_pcie_of_data *)match->data;
+ variant = (enum artpec_pcie_variants)data->variant;
mode = (enum dw_pcie_device_mode)data->mode;

artpec6_pcie = devm_kzalloc(dev, sizeof(*artpec6_pcie), GFP_KERNEL);
@@ -379,6 +537,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
pci->ops = &dw_pcie_ops;

artpec6_pcie->pci = pci;
+ artpec6_pcie->variant = variant;
artpec6_pcie->mode = mode;

dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
@@ -430,10 +589,22 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
}

static const struct artpec_pcie_of_data artpec6_pcie_rc_of_data = {
+ .variant = ARTPEC6,
.mode = DW_PCIE_RC_TYPE,
};

static const struct artpec_pcie_of_data artpec6_pcie_ep_of_data = {
+ .variant = ARTPEC6,
+ .mode = DW_PCIE_EP_TYPE,
+};
+
+static const struct artpec_pcie_of_data artpec7_pcie_rc_of_data = {
+ .variant = ARTPEC7,
+ .mode = DW_PCIE_RC_TYPE,
+};
+
+static const struct artpec_pcie_of_data artpec7_pcie_ep_of_data = {
+ .variant = ARTPEC7,
.mode = DW_PCIE_EP_TYPE,
};

@@ -446,6 +617,14 @@ static const struct of_device_id artpec6_pcie_of_match[] = {
.compatible = "axis,artpec6-pcie-ep",
.data = &artpec6_pcie_ep_of_data,
},
+ {
+ .compatible = "axis,artpec7-pcie",
+ .data = &artpec7_pcie_rc_of_data,
+ },
+ {
+ .compatible = "axis,artpec7-pcie-ep",
+ .data = &artpec7_pcie_ep_of_data,
+ },
{},
};

--
2.14.2