Hi Joel,

The series looks good.

I've got a couple of patches on the ipmi list that this will conflict
with:

 https://sourceforge.net/p/openipmi/mailman/message/37345391/
 https://lore.kernel.org/all/20210903015314.177987-1-joel@jms.id.au/ (local)

If there's no feedback from others I suggest basing your series on top
of those, and sending them to Corey on the ipmi list to merge.

Looks good, will do.

Thanks,
Anton

Cheers,

Joel

quoted

Signed-off-by: Anton Blanchard <redacted>
---
 .../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, &reg);
+       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)); +
+       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 =
&microwatt_bt_bmc_ops }, { },
 };

--
2.31.1