[PATCH v4 2/3] pcie-designware: add iATU Unroll feature
From: Joao Pinto
Date: Tue Aug 09 2016 - 12:35:51 EST
This patch adds the support to the new iATU mechanism that will be used
from Core version 4.80, which is called iATU Unroll.
The new Cores can support the iATU Unroll or support the "old" iATU
method now called Legacy Mode. The driver is perfectly capable of
performing well for both.
In order to make sure that the iATU is really enabled a for loop was
introduced in dw_pcie_prog_outbound_atu() to improve reliability.
Signed-off-by: Joao Pinto <jpinto@xxxxxxxxxxxx>
---
changes v3->v4:
- Unroll Mode is now obtained before the host initialization
- The iATU enable check loop is now returning instead of only
interrupting the loop
changes v2->v3 (Bjorn Helgaas):
- Unused *CTRL3 and *UPPR iATU Unroll registers were removed
- Inbound addr builder macro was removed to simplifiy the code
- *readl_unroll and *writel_unroll functions were simplified. Now the
scope is always outbound.
- dw_pcie_get_atu_mode changed to return the status
- iATU enable check routine was improved in dw_pcie_prog_outbound_atu()
changes v1->v2:
- Patch was breaking kernel build due to bad definition in macro funtion.
- Rebased on top of pci/next.
drivers/pci/host/pcie-designware.c | 131 ++++++++++++++++++++++++++++++++-----
drivers/pci/host/pcie-designware.h | 1 +
2 files changed, 116 insertions(+), 16 deletions(-)
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 6fb88de..3fb9036 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -31,6 +31,11 @@
#define LINK_WAIT_USLEEP_MIN 90000
#define LINK_WAIT_USLEEP_MAX 100000
+/* Parameters for the waiting for iATU enabled routine */
+#define LINK_WAIT_MAX_IATU_RETRIES 5
+#define LINK_WAIT_IATU_MIN 9000
+#define LINK_WAIT_IATU_MAX 10000
+
/* Synopsis specific PCIE configuration registers */
#define PCIE_PORT_LINK_CONTROL 0x710
#define PORT_LINK_MODE_MASK (0x3f << 16)
@@ -75,6 +80,26 @@
#define PCIE_ATU_FUNC(x) (((x) & 0x7) << 16)
#define PCIE_ATU_UPPER_TARGET 0x91C
+/*
+ * iATU unroll specific registers and definitions
+ * from 4.80 core version the address translation will be made by unroll
+ */
+
+/* Registers */
+#define PCIE_ATU_UNR_REGION_CTRL1 0x00
+#define PCIE_ATU_UNR_REGION_CTRL2 0x01
+#define PCIE_ATU_UNR_LOWER_BASE 0x02
+#define PCIE_ATU_UNR_UPPER_BASE 0x03
+#define PCIE_ATU_UNR_LIMIT 0x04
+#define PCIE_ATU_UNR_LOWER_TARGET 0x05
+#define PCIE_ATU_UNR_UPPER_TARGET 0x06
+
+/* Register address builder */
+#define PCIE_GET_ATU_OUTB_UNR_REG_ADDR(region, register) \
+ ((0x3 << 20) | (region << 9) | \
+ (register << 2))
+/* End of Unroll specific */
+
/* PCIe Port Logic registers */
#define PLR_OFFSET 0x700
#define PCIE_PHY_DEBUG_R1 (PLR_OFFSET + 0x2c)
@@ -136,6 +161,28 @@ static inline void dw_pcie_writel_rc(struct pcie_port *pp, u32 val, u32 reg)
writel(val, pp->dbi_base + reg);
}
+static inline void dw_pcie_readl_unroll(struct pcie_port *pp,
+ u32 index, u32 reg, u32 *val)
+{
+ u32 reg_addr = PCIE_GET_ATU_OUTB_UNR_REG_ADDR(index, reg);
+
+ if (pp->ops->readl_rc)
+ pp->ops->readl_rc(pp, pp->dbi_base + reg_addr, val);
+ else
+ *val = readl(pp->dbi_base + reg_addr);
+}
+
+static inline void dw_pcie_writel_unroll(struct pcie_port *pp,
+ u32 index, u32 val, u32 reg)
+{
+ u32 reg_addr = PCIE_GET_ATU_OUTB_UNR_REG_ADDR(index, reg);
+
+ if (pp->ops->writel_rc)
+ pp->ops->writel_rc(pp, val, pp->dbi_base + reg_addr);
+ else
+ writel(val, pp->dbi_base + reg_addr);
+}
+
static int dw_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
u32 *val)
{
@@ -157,24 +204,61 @@ static int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
static void dw_pcie_prog_outbound_atu(struct pcie_port *pp, int index,
int type, u64 cpu_addr, u64 pci_addr, u32 size)
{
- u32 val;
-
- dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | index,
- PCIE_ATU_VIEWPORT);
- dw_pcie_writel_rc(pp, lower_32_bits(cpu_addr), PCIE_ATU_LOWER_BASE);
- dw_pcie_writel_rc(pp, upper_32_bits(cpu_addr), PCIE_ATU_UPPER_BASE);
- dw_pcie_writel_rc(pp, lower_32_bits(cpu_addr + size - 1),
- PCIE_ATU_LIMIT);
- dw_pcie_writel_rc(pp, lower_32_bits(pci_addr), PCIE_ATU_LOWER_TARGET);
- dw_pcie_writel_rc(pp, upper_32_bits(pci_addr), PCIE_ATU_UPPER_TARGET);
- dw_pcie_writel_rc(pp, type, PCIE_ATU_CR1);
- dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
+ u32 val = 0;
+ u32 retries = 0;
+
+ if (pp->iatu_unroll_status) {
+ dw_pcie_writel_unroll(pp, index,
+ lower_32_bits(cpu_addr), PCIE_ATU_UNR_LOWER_BASE);
+ dw_pcie_writel_unroll(pp, index,
+ upper_32_bits(cpu_addr), PCIE_ATU_UNR_UPPER_BASE);
+ dw_pcie_writel_unroll(pp, index,
+ lower_32_bits(cpu_addr + size - 1), PCIE_ATU_UNR_LIMIT);
+ dw_pcie_writel_unroll(pp, index,
+ lower_32_bits(pci_addr), PCIE_ATU_UNR_LOWER_TARGET);
+ dw_pcie_writel_unroll(pp, index,
+ upper_32_bits(pci_addr), PCIE_ATU_UNR_UPPER_TARGET);
+ dw_pcie_writel_unroll(pp, index,
+ type, PCIE_ATU_UNR_REGION_CTRL1);
+ dw_pcie_writel_unroll(pp, index,
+ PCIE_ATU_ENABLE, PCIE_ATU_UNR_REGION_CTRL2);
+ } else {
+ dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | index,
+ PCIE_ATU_VIEWPORT);
+ dw_pcie_writel_rc(pp, lower_32_bits(cpu_addr),
+ PCIE_ATU_LOWER_BASE);
+ dw_pcie_writel_rc(pp, upper_32_bits(cpu_addr),
+ PCIE_ATU_UPPER_BASE);
+ dw_pcie_writel_rc(pp, lower_32_bits(cpu_addr + size - 1),
+ PCIE_ATU_LIMIT);
+ dw_pcie_writel_rc(pp, lower_32_bits(pci_addr),
+ PCIE_ATU_LOWER_TARGET);
+ dw_pcie_writel_rc(pp, upper_32_bits(pci_addr),
+ PCIE_ATU_UPPER_TARGET);
+ dw_pcie_writel_rc(pp, type, PCIE_ATU_CR1);
+ dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
+ }
/*
- * Make sure ATU enable takes effect before any subsequent config
- * and I/O accesses.
- */
- dw_pcie_readl_rc(pp, PCIE_ATU_CR2, &val);
+ * Make sure ATU enable takes effect before any subsequent config
+ * and I/O accesses.
+ */
+ for (retries = 0; retries < LINK_WAIT_MAX_IATU_RETRIES; retries++) {
+
+ if (pp->iatu_unroll_status) {
+ dw_pcie_readl_unroll(pp, index,
+ PCIE_ATU_UNR_REGION_CTRL2, &val);
+ } else {
+ dw_pcie_readl_rc(pp, PCIE_ATU_CR2, &val);
+ }
+
+ if (val == PCIE_ATU_ENABLE)
+ break;
+
+ usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
+ }
+
+ dev_dbg(pp->dev, "iATU is not being enabled\n");
}
static struct irq_chip dw_msi_irq_chip = {
@@ -433,6 +517,19 @@ static const struct irq_domain_ops msi_domain_ops = {
.map = dw_pcie_msi_map,
};
+static u8 dw_pcie_get_atu_mode(struct pcie_port *pp)
+{
+ u32 val = 0;
+
+ /* Check if the iATU unroll is enabled or not */
+ dw_pcie_readl_rc(pp, PCIE_ATU_VIEWPORT, &val);
+
+ if (val == 0xFFFFFFFF)
+ return 1; /* enabled */
+
+ return 0; /* disabled */
+}
+
int dw_pcie_host_init(struct pcie_port *pp)
{
struct device_node *np = pp->dev->of_node;
@@ -552,6 +649,8 @@ int dw_pcie_host_init(struct pcie_port *pp)
if (pp->ops->host_init)
pp->ops->host_init(pp);
+ pp->iatu_unroll_status = dw_pcie_get_atu_mode(pp);
+
pp->root_bus_nr = pp->busn->start;
if (IS_ENABLED(CONFIG_PCI_MSI)) {
bus = pci_scan_root_bus_msi(pp->dev, pp->root_bus_nr,
diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
index 384e79b..354a981 100644
--- a/drivers/pci/host/pcie-designware.h
+++ b/drivers/pci/host/pcie-designware.h
@@ -48,6 +48,7 @@ struct pcie_port {
int msi_irq;
struct irq_domain *irq_domain;
unsigned long msi_data;
+ u8 iatu_unroll_status;
DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
};
--
1.8.1.5