On 10/6/21 04:12, Anton Blanchard wrote:
This adds the Microwatt specific bits, including interrupt support.
Signed-off-by: Anton Blanchard <an...@ozlabs.org>
---
.../devicetree/bindings/ipmi/ibt-bmc.txt | 1 +
drivers/char/ipmi/Kconfig | 8 ++-
drivers/char/ipmi/bt-bmc.c | 69 +++++++++++++++++++
3 files changed, 75 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/ipmi/ibt-bmc.txt
b/Documentation/devicetree/bindings/ipmi/ibt-bmc.txt
index 78ee716a950e..1b661daf0193 100644
--- a/Documentation/devicetree/bindings/ipmi/ibt-bmc.txt
+++ b/Documentation/devicetree/bindings/ipmi/ibt-bmc.txt
@@ -9,6 +9,7 @@ Required properties:
- compatible : should be one of
"aspeed,ast2400-ibt-bmc"
"aspeed,ast2500-ibt-bmc"
+ "ibm,microwatt-ibt-bmc"
- reg: physical address and size of the registers
Optional properties:
diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig
index 8b2f0f675e5f..079302f4eef2 100644
--- a/drivers/char/ipmi/Kconfig
+++ b/drivers/char/ipmi/Kconfig
@@ -152,13 +152,15 @@ config IPMI_KCS_BMC_SERIO
called kcs_bmc_serio.
config BT_IPMI_BMC
- depends on ARCH_ASPEED || COMPILE_TEST
+ depends on ARCH_ASPEED || PPC_MICROWATT || COMPILE_TEST
depends on REGMAP && REGMAP_MMIO && MFD_SYSCON
tristate "BT IPMI bmc driver"
help
Provides a driver for the BT (Block Transfer) IPMI interface
- found on Aspeed SOCs (AST2400 and AST2500). The driver
- implements the BMC side of the BT interface.
+ found on Aspeed SOCs (AST2400 and AST2500) as well as the OpenPOWER
+ LPC peripheral macro at
+ <https://github.com/OpenPOWERFoundation/lpcperipheral>
+ The driver implements the BMC side of the BT interface.
config IPMB_DEVICE_INTERFACE
tristate 'IPMB Interface handler'
diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c
index b48e04405ac4..24327b57c60b 100644
--- a/drivers/char/ipmi/bt-bmc.c
+++ b/drivers/char/ipmi/bt-bmc.c
@@ -41,6 +41,11 @@
#define BT_CR2_IRQ_HBUSY 0x40
#define ASPEED_BT_CR3 0xc
+#define MICROWATT_IRQ_MASK 0x0
+#define MICROWATT_IRQ_STATUS 0x4
+#define IRQ_HOST_TO_BMC_ATTN 0x1
+#define IRQ_HOST_NOT_BUSY 0x2
+
#define BT_CTRL 0x10
#define BT_CTRL_B_BUSY 0x80
#define BT_CTRL_H_BUSY 0x40
@@ -395,6 +400,27 @@ static irqreturn_t aspeed_bt_bmc_irq(int irq, void *arg)
return IRQ_HANDLED;
}
+static irqreturn_t microwatt_bt_bmc_irq(int irq, void *arg)
+{
+ struct bt_bmc *bt_bmc = arg;
+ u32 reg;
+ int rc;
+
+ rc = regmap_read(bt_bmc->map, bt_bmc->offset + MICROWATT_IRQ_STATUS,
®);
+ if (rc)
+ return IRQ_NONE;
+
+ /* Interrupt wasn't something we knew about */
+ if (!(reg & (IRQ_HOST_TO_BMC_ATTN | IRQ_HOST_NOT_BUSY)))
+ return IRQ_NONE;
+
+ /* ack all pending IRQs */
+ regmap_write(bt_bmc->map, bt_bmc->offset + MICROWATT_IRQ_STATUS, 0);
+
+ wake_up(&bt_bmc->queue);
+ return IRQ_HANDLED;
+}
+
static int aspeed_bt_bmc_config_irq(struct bt_bmc *bt_bmc,
struct platform_device *pdev)
{
@@ -446,6 +472,48 @@ static const struct bt_bmc_ops aspeed_bt_bmc_ops = {
.enable_bt = aspeed_enable_bt,
};
+static int microwatt_bt_bmc_config_irq(struct bt_bmc *bt_bmc,
+ struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int rc;
+
+ bt_bmc->irq = platform_get_irq_optional(pdev, 0);
+ if (bt_bmc->irq < 0)
+ return bt_bmc->irq;
+
+ rc = devm_request_irq(dev, bt_bmc->irq, microwatt_bt_bmc_irq,
IRQF_SHARED,
+ DEVICE_NAME, bt_bmc);
+ if (rc < 0) {
+ dev_warn(dev, "Unable to request IRQ %d\n", bt_bmc->irq);
+ bt_bmc->irq = rc;
+ return rc;
+ }
+
+ /*
+ * Configure the hardware to give us an interrupt whenever the H2B
+ * bit is set or the HBUSY bit is cleared.
+ *
+ * H2B will be asserted when the bmc has data for us; HBUSY
+ * will be cleared (along with B2H) when we can write the next
+ * message to the BT buffer
+ */
+ rc = regmap_update_bits(bt_bmc->map, bt_bmc->offset +
MICROWATT_IRQ_MASK,
+ (IRQ_HOST_TO_BMC_ATTN | IRQ_HOST_NOT_BUSY),
+ (IRQ_HOST_TO_BMC_ATTN | IRQ_HOST_NOT_BUSY));
This is the only difference. May be we could introduce a ->config_irq_hw()
handler to keep a larger part common. No big deal.
Reviewed-by: Cédric Le Goater <c...@kaod.org>
C.
+ return rc;
+}
+
+static void microwatt_enable_bt(struct bt_bmc *bt_bmc)
+{
+}
+
+static const struct bt_bmc_ops microwatt_bt_bmc_ops = {
+ .config_irq = microwatt_bt_bmc_config_irq,
+ .enable_bt = microwatt_enable_bt,
+};
+
static int bt_bmc_probe(struct platform_device *pdev)
{
struct bt_bmc *bt_bmc;
@@ -530,6 +598,7 @@ static int bt_bmc_remove(struct platform_device *pdev)
static const struct of_device_id bt_bmc_match[] = {
{ .compatible = "aspeed,ast2400-ibt-bmc", .data = &aspeed_bt_bmc_ops },
{ .compatible = "aspeed,ast2500-ibt-bmc", .data = &aspeed_bt_bmc_ops },
+ { .compatible = "ibm,microwatt-ibt-bmc", .data = µwatt_bt_bmc_ops
},
{ },
};
