On 2021-01-13 11:39, Jianjun Wang wrote:
Add MSI support for MediaTek Gen3 PCIe controller.
This PCIe controller supports up to 256 MSI vectors, the MSI hardware
block diagram is as follows:
+-----+
| GIC |
+-----+
^
|
port->irq
|
+-+-+-+-+-+-+-+-+
|0|1|2|3|4|5|6|7| (PCIe intc)
+-+-+-+-+-+-+-+-+
^ ^ ^
| | ... |
+-------+ +------+ +-----------+
| | |
+-+-+---+--+--+ +-+-+---+--+--+ +-+-+---+--+--+
|0|1|...|30|31| |0|1|...|30|31| |0|1|...|30|31| (MSI sets)
+-+-+---+--+--+ +-+-+---+--+--+ +-+-+---+--+--+
^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
| | | | | | | | | | | | (MSI vectors)
| | | | | | | | | | | |
(MSI SET0) (MSI SET1) ... (MSI SET7)
With 256 MSI vectors supported, the MSI vectors are composed of 8 sets,
each set has its own address for MSI message, and supports 32 MSI
vectors
to generate interrupt.
Signed-off-by: Jianjun Wang <jianjun.w...@mediatek.com>
Acked-by: Ryder Lee <ryder....@mediatek.com>
---
drivers/pci/controller/pcie-mediatek-gen3.c | 261 ++++++++++++++++++++
1 file changed, 261 insertions(+)
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c
b/drivers/pci/controller/pcie-mediatek-gen3.c
index 7979a2856c35..471d97cd1ef9 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -14,6 +14,7 @@
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_clk.h>
#include <linux/of_pci.h>
@@ -52,11 +53,28 @@
#define PCIE_LINK_STATUS_REG 0x154
#define PCIE_PORT_LINKUP BIT(8)
+#define PCIE_MSI_SET_NUM 8
+#define PCIE_MSI_IRQS_PER_SET 32
+#define PCIE_MSI_IRQS_NUM \
+ (PCIE_MSI_IRQS_PER_SET * (PCIE_MSI_SET_NUM))
Spurious inner bracketing.
+
#define PCIE_INT_ENABLE_REG 0x180
+#define PCIE_MSI_ENABLE GENMASK(PCIE_MSI_SET_NUM + 8 -
1, 8)
+#define PCIE_MSI_SHIFT 8
#define PCIE_INTX_SHIFT 24
#define PCIE_INTX_MASK GENMASK(27, 24)
#define PCIE_INT_STATUS_REG 0x184
+#define PCIE_MSI_SET_ENABLE_REG 0x190
+#define PCIE_MSI_SET_ENABLE GENMASK(PCIE_MSI_SET_NUM - 1, 0)
+
+#define PCIE_MSI_SET_BASE_REG 0xc00
+#define PCIE_MSI_SET_OFFSET 0x10
+#define PCIE_MSI_SET_STATUS_OFFSET 0x04
+#define PCIE_MSI_SET_ENABLE_OFFSET 0x08
+
+#define PCIE_MSI_SET_ADDR_HI_BASE 0xc80
+#define PCIE_MSI_SET_ADDR_HI_OFFSET 0x04
#define PCIE_TRANS_TABLE_BASE_REG 0x800
#define PCIE_ATR_SRC_ADDR_MSB_OFFSET 0x4
@@ -76,6 +94,18 @@
#define PCIE_ATR_TLP_TYPE_MEM PCIE_ATR_TLP_TYPE(0)
#define PCIE_ATR_TLP_TYPE_IO PCIE_ATR_TLP_TYPE(2)
+/**
+ * struct mtk_pcie_msi - MSI information for each set
+ * @dev: pointer to PCIe device
+ * @base: IO mapped register base
+ * @msg_addr: MSI message address
+ */
+struct mtk_msi_set {
+ struct device *dev;
+ void __iomem *base;
+ phys_addr_t msg_addr;
+};
+
/**
* struct mtk_pcie_port - PCIe port information
* @dev: pointer to PCIe device
@@ -88,6 +118,11 @@
* @num_clks: PCIe clocks count for this port
* @irq: PCIe controller interrupt number
* @intx_domain: legacy INTx IRQ domain
+ * @msi_domain: MSI IRQ domain
+ * @msi_bottom_domain: MSI IRQ bottom domain
+ * @msi_sets: MSI sets information
+ * @lock: lock protecting IRQ bit map
+ * @msi_irq_in_use: bit map for assigned MSI IRQ
*/
struct mtk_pcie_port {
struct device *dev;
@@ -101,6 +136,11 @@ struct mtk_pcie_port {
int irq;
struct irq_domain *intx_domain;
+ struct irq_domain *msi_domain;
+ struct irq_domain *msi_bottom_domain;
+ struct mtk_msi_set msi_sets[PCIE_MSI_SET_NUM];
+ struct mutex lock;
+ DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM);
};
/**
@@ -243,6 +283,15 @@ static int mtk_pcie_startup_port(struct
mtk_pcie_port *port)
return err;
}
+ /* Enable MSI */
+ val = readl_relaxed(port->base + PCIE_MSI_SET_ENABLE_REG);
+ val |= PCIE_MSI_SET_ENABLE;
+ writel_relaxed(val, port->base + PCIE_MSI_SET_ENABLE_REG);
+
+ val = readl_relaxed(port->base + PCIE_INT_ENABLE_REG);
+ val |= PCIE_MSI_ENABLE;
+ writel_relaxed(val, port->base + PCIE_INT_ENABLE_REG);
+
/* Set PCIe translation windows */
resource_list_for_each_entry(entry, &host->windows) {
struct resource *res = entry->res;
@@ -286,6 +335,129 @@ static int mtk_pcie_set_affinity(struct irq_data
*data,
return -EINVAL;
}
+static struct irq_chip mtk_msi_irq_chip = {
+ .name = "MSI",
+ .irq_ack = irq_chip_ack_parent,
+};
+
+static struct msi_domain_info mtk_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_PCI_MSIX |
+ MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_MULTI_PCI_MSI),
+ .chip = &mtk_msi_irq_chip,
+};
+
+static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg
*msg)
+{
+ struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
+ unsigned long hwirq;
+
+ hwirq = data->hwirq % PCIE_MSI_IRQS_PER_SET;
+
+ msg->address_hi = upper_32_bits(msi_set->msg_addr);
+ msg->address_lo = lower_32_bits(msi_set->msg_addr);
+ msg->data = hwirq;
+ dev_dbg(msi_set->dev, "msi#%#lx address_hi %#x address_lo %#x data
%d\n",
+ hwirq, msg->address_hi, msg->address_lo, msg->data);
+}
+
+static void mtk_msi_bottom_irq_ack(struct irq_data *data)
+{
+ struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
+ unsigned long hwirq;
+
+ hwirq = data->hwirq % PCIE_MSI_IRQS_PER_SET;
+
+ writel_relaxed(BIT(hwirq), msi_set->base +
PCIE_MSI_SET_STATUS_OFFSET);
+}
+
+static struct irq_chip mtk_msi_bottom_irq_chip = {
+ .irq_ack = mtk_msi_bottom_irq_ack,
+ .irq_compose_msi_msg = mtk_compose_msi_msg,
+ .irq_set_affinity = mtk_pcie_set_affinity,
+ .name = "PCIe",
nit: "MSI", rather than "PCIe".
+};
+
+static int mtk_msi_bottom_domain_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *arg)
+{
+ struct mtk_pcie_port *port = domain->host_data;
+ struct mtk_msi_set *msi_set;
+ int i, hwirq, set_idx;
+
+ mutex_lock(&port->lock);
+
+ hwirq = bitmap_find_free_region(port->msi_irq_in_use,
PCIE_MSI_IRQS_NUM,
+ order_base_2(nr_irqs));
+
+ mutex_unlock(&port->lock);
+
+ if (hwirq < 0)
+ return -ENOSPC;
+
+ set_idx = hwirq / PCIE_MSI_IRQS_PER_SET;
+ msi_set = &port->msi_sets[set_idx];
+
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_info(domain, virq + i, hwirq + i,
+ &mtk_msi_bottom_irq_chip, msi_set,
+ handle_edge_irq, NULL, NULL);
+
+ return 0;
+}
+
+static void mtk_msi_bottom_domain_free(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct mtk_pcie_port *port = domain->host_data;
+ struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+
+ mutex_lock(&port->lock);
+
+ bitmap_clear(port->msi_irq_in_use, data->hwirq, nr_irqs);
+
+ mutex_unlock(&port->lock);
+
+ irq_domain_free_irqs_common(domain, virq, nr_irqs);
+}
+
+static int mtk_msi_bottom_domain_activate(struct irq_domain *domain,
+ struct irq_data *data, bool reserve)
+{
+ struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
+ unsigned long hwirq;
+ u32 val;
+
+ hwirq = data->hwirq % PCIE_MSI_IRQS_PER_SET;
+
+ val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
+ val |= BIT(hwirq);
+ writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
This isn't an activate. This is an unmask, which suffers from the same
issue as its INTx sibling.
+
+ return 0;
+}
+
+static void mtk_msi_bottom_domain_deactivate(struct irq_domain
*domain,
+ struct irq_data *data)
+{
+ struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
+ unsigned long hwirq;
+ u32 val;
+
+ hwirq = data->hwirq % PCIE_MSI_IRQS_PER_SET;
+
+ val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
+ val &= ~BIT(hwirq);
+ writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
+}
Same thing, this is a mask. I don't think this block requires any
activate/deactivate callbacks for its lower irqdomain.
As it stands, you can't mask a MSI at the low-level, which is
pretty bad (you need to mask them at the PCI source, which can
end-up disabling all vectors in the case of Multi-MSI).
+
+static const struct irq_domain_ops mtk_msi_bottom_domain_ops = {
+ .alloc = mtk_msi_bottom_domain_alloc,
+ .free = mtk_msi_bottom_domain_free,
+ .activate = mtk_msi_bottom_domain_activate,
+ .deactivate = mtk_msi_bottom_domain_deactivate,
+};
+
static void mtk_intx_mask(struct irq_data *data)
{
struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
@@ -350,6 +522,9 @@ static int mtk_pcie_init_irq_domains(struct
mtk_pcie_port *port,
{
struct device *dev = port->dev;
struct device_node *intc_node;
+ struct fwnode_handle *fwnode = of_node_to_fwnode(node);
+ struct msi_domain_info *info;
+ int i, ret;
/* Setup INTx */
intc_node = of_get_child_by_name(node, "interrupt-controller");
@@ -365,7 +540,57 @@ static int mtk_pcie_init_irq_domains(struct
mtk_pcie_port *port,
return -ENODEV;
}
+ /* Setup MSI */
+ mutex_init(&port->lock);
+
+ port->msi_bottom_domain = irq_domain_add_linear(node,
PCIE_MSI_IRQS_NUM,
+ &mtk_msi_bottom_domain_ops, port);
+ if (!port->msi_bottom_domain) {
+ dev_info(dev, "failed to create MSI bottom domain\n");
+ ret = -ENODEV;
+ goto err_msi_bottom_domain;
+ }
+
+ info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ ret = -ENOMEM;
+ goto err_msi_bottom_domain;
+ }
+
+ memcpy(info, &mtk_msi_domain_info, sizeof(*info));
Why the memcpy()? There is nothing in mtk_msi_domain_info that is
per-domain, and you should be able to use this structure for all
ports, shouldn't you?
+ info->chip_data = port;
+
+ port->msi_domain = pci_msi_create_irq_domain(fwnode, info,
+ port->msi_bottom_domain);
+ if (!port->msi_domain) {
+ dev_info(dev, "failed to create MSI domain\n");
+ ret = -ENODEV;
+ goto err_msi_domain;
+ }
+
+ for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
+ struct mtk_msi_set *msi_set = &port->msi_sets[i];
+
+ msi_set->dev = port->dev;
Given that this is only used in a debug message, and that the addresses
are already non-ambiguous, you can probably remove this field.
+ msi_set->base = port->base + PCIE_MSI_SET_BASE_REG +
+ i * PCIE_MSI_SET_OFFSET;
+ msi_set->msg_addr = port->reg_base + PCIE_MSI_SET_BASE_REG +
+ i * PCIE_MSI_SET_OFFSET;
+
+ writel_relaxed(lower_32_bits(msi_set->msg_addr), msi_set->base);
+ writel_relaxed(upper_32_bits(msi_set->msg_addr),
+ port->base + PCIE_MSI_SET_ADDR_HI_BASE +
+ i * PCIE_MSI_SET_ADDR_HI_OFFSET);
Please a comment on what this is doing...
+ }
+
return 0;
+
+err_msi_domain:
+ irq_domain_remove(port->msi_bottom_domain);
+err_msi_bottom_domain:
+ irq_domain_remove(port->intx_domain);
+
+ return ret;
}
static void mtk_pcie_irq_teardown(struct mtk_pcie_port *port)
@@ -375,9 +600,34 @@ static void mtk_pcie_irq_teardown(struct
mtk_pcie_port *port)
if (port->intx_domain)
irq_domain_remove(port->intx_domain);
+ if (port->msi_domain)
+ irq_domain_remove(port->msi_domain);
+
+ if (port->msi_bottom_domain)
+ irq_domain_remove(port->msi_bottom_domain);
+
irq_dispose_mapping(port->irq);
}
+static void mtk_pcie_msi_handler(struct mtk_pcie_port *port, int
set_idx)
+{
+ struct mtk_msi_set *msi_set = &port->msi_sets[set_idx];
+ unsigned long msi_enable, msi_status;
+ unsigned int virq;
+ irq_hw_number_t bit, hwirq;
+
+ msi_enable = readl_relaxed(msi_set->base +
PCIE_MSI_SET_ENABLE_OFFSET);
+ while ((msi_status =
+ readl_relaxed(msi_set->base + PCIE_MSI_SET_STATUS_OFFSET) &
+ msi_enable)) {
+ for_each_set_bit(bit, &msi_status, PCIE_MSI_IRQS_PER_SET) {
+ hwirq = bit + set_idx * PCIE_MSI_IRQS_PER_SET;
+ virq = irq_find_mapping(port->msi_bottom_domain, hwirq);
+ generic_handle_irq(virq);
+ }
+ }
This doesn't look very readable. How about something like:
do {
msi_status = readl_relaxed(...) & msi_enable;
if (!msi_status)
break;
for_each_set_bit(...) {
...
}
} while(true);
+}
+
static void mtk_pcie_irq_handler(struct irq_desc *desc)
{
struct mtk_pcie_port *port = irq_desc_get_handler_data(desc);
@@ -398,6 +648,17 @@ static void mtk_pcie_irq_handler(struct irq_desc
*desc)
}
}
+ if (status & PCIE_MSI_ENABLE) {
Same comment has for INTx.
+ irq_bit = PCIE_MSI_SHIFT;
+ for_each_set_bit_from(irq_bit, &status, PCIE_MSI_SET_NUM +
+ PCIE_MSI_SHIFT) {
+ mtk_pcie_msi_handler(port, irq_bit - PCIE_MSI_SHIFT);
+
+ writel_relaxed(BIT(irq_bit),
+ port->base + PCIE_INT_STATUS_REG);
+ }
+ }
+
chained_irq_exit(irqchip, desc);
}
Thanks,
M.
--
Jazz is not dead. It just smells funny...
