[PATCH v2 8/8] misc: keba: Add UART devices

From: Gerhard Engleder
Date: Fri Oct 11 2024 - 15:13:34 EST


From: Gerhard Engleder <eg@xxxxxxxx>

Add support for the UART auxiliary devices. This enables access to up to
3 different UARTs, which are implemented in the FPGA.

Signed-off-by: Gerhard Engleder <eg@xxxxxxxx>
---
drivers/misc/keba/cp500.c | 104 ++++++++++++++++++++++++++++++++++++++
include/linux/misc/keba.h | 12 +++++
2 files changed, 116 insertions(+)

diff --git a/drivers/misc/keba/cp500.c b/drivers/misc/keba/cp500.c
index afd4d7c06cee..255d3022dae8 100644
--- a/drivers/misc/keba/cp500.c
+++ b/drivers/misc/keba/cp500.c
@@ -46,6 +46,9 @@

/* MSIX */
#define CP500_AXI_MSIX 3
+#define CP500_RFB_UART_MSIX 4
+#define CP500_DEBUG_UART_MSIX 5
+#define CP500_SI1_UART_MSIX 6
#define CP500_NUM_MSIX 8
#define CP500_NUM_MSIX_NO_MMI 2
#define CP500_NUM_MSIX_NO_AXI 3
@@ -75,6 +78,7 @@
struct cp500_dev_info {
off_t offset;
size_t size;
+ unsigned int msix;
};

struct cp500_devs {
@@ -83,6 +87,9 @@ struct cp500_devs {
struct cp500_dev_info i2c;
struct cp500_dev_info fan;
struct cp500_dev_info batt;
+ struct cp500_dev_info uart0_rfb;
+ struct cp500_dev_info uart1_dbg;
+ struct cp500_dev_info uart2_si1;
};

/* list of devices within FPGA of CP035 family (CP035, CP056, CP057) */
@@ -92,6 +99,8 @@ static struct cp500_devs cp035_devices = {
.i2c = { 0x4000, SZ_4K },
.fan = { 0x9000, SZ_4K },
.batt = { 0xA000, SZ_4K },
+ .uart0_rfb = { 0xB000, SZ_4K, CP500_RFB_UART_MSIX },
+ .uart2_si1 = { 0xD000, SZ_4K, CP500_SI1_UART_MSIX },
};

/* list of devices within FPGA of CP505 family (CP503, CP505, CP507) */
@@ -101,6 +110,8 @@ static struct cp500_devs cp505_devices = {
.i2c = { 0x5000, SZ_4K },
.fan = { 0x9000, SZ_4K },
.batt = { 0xA000, SZ_4K },
+ .uart0_rfb = { 0xB000, SZ_4K, CP500_RFB_UART_MSIX },
+ .uart2_si1 = { 0xD000, SZ_4K, CP500_SI1_UART_MSIX },
};

/* list of devices within FPGA of CP520 family (CP520, CP530) */
@@ -110,6 +121,8 @@ static struct cp500_devs cp520_devices = {
.i2c = { 0x5000, SZ_4K },
.fan = { 0x8000, SZ_4K },
.batt = { 0x9000, SZ_4K },
+ .uart0_rfb = { 0xC000, SZ_4K, CP500_RFB_UART_MSIX },
+ .uart1_dbg = { 0xD000, SZ_4K, CP500_DEBUG_UART_MSIX },
};

struct cp500_nvmem {
@@ -135,6 +148,9 @@ struct cp500 {
struct keba_i2c_auxdev *i2c;
struct keba_fan_auxdev *fan;
struct keba_batt_auxdev *batt;
+ struct keba_uart_auxdev *uart0_rfb;
+ struct keba_uart_auxdev *uart1_dbg;
+ struct keba_uart_auxdev *uart2_si1;

/* ECM EtherCAT BAR */
resource_size_t ecm_hwbase;
@@ -510,6 +526,55 @@ static int cp500_register_batt(struct cp500 *cp500)
return 0;
}

+static void cp500_uart_release(struct device *dev)
+{
+ struct keba_uart_auxdev *uart =
+ container_of(dev, struct keba_uart_auxdev, auxdev.dev);
+
+ kfree(uart);
+}
+
+static int cp500_register_uart(struct cp500 *cp500,
+ struct keba_uart_auxdev **uart, const char *name,
+ struct cp500_dev_info *info, unsigned int irq)
+{
+ int ret;
+
+ *uart = kzalloc(sizeof(**uart), GFP_KERNEL);
+ if (!*uart)
+ return -ENOMEM;
+
+ (*uart)->auxdev.name = name;
+ (*uart)->auxdev.id = 0;
+ (*uart)->auxdev.dev.release = cp500_uart_release;
+ (*uart)->auxdev.dev.parent = &cp500->pci_dev->dev;
+ (*uart)->io = (struct resource) {
+ /* UART register area */
+ .start = (resource_size_t) cp500->sys_hwbase + info->offset,
+ .end = (resource_size_t) cp500->sys_hwbase + info->offset +
+ info->size - 1,
+ .flags = IORESOURCE_MEM,
+ };
+ (*uart)->irq = irq;
+
+ ret = auxiliary_device_init(&(*uart)->auxdev);
+ if (ret) {
+ kfree(*uart);
+ *uart = NULL;
+
+ return ret;
+ }
+ ret = __auxiliary_device_add(&(*uart)->auxdev, "keba");
+ if (ret) {
+ auxiliary_device_uninit(&(*uart)->auxdev);
+ *uart = NULL;
+
+ return ret;
+ }
+
+ return 0;
+}
+
static int cp500_nvmem_read(void *priv, unsigned int offset, void *val,
size_t bytes)
{
@@ -668,6 +733,33 @@ static void cp500_register_auxiliary_devs(struct cp500 *cp500)
dev_warn(dev, "Failed to register fan!\n");
if (cp500_register_batt(cp500))
dev_warn(dev, "Failed to register battery!\n");
+ if (cp500->devs->uart0_rfb.size &&
+ cp500->devs->uart0_rfb.msix < cp500->msix_num) {
+ int irq = pci_irq_vector(cp500->pci_dev,
+ cp500->devs->uart0_rfb.msix);
+
+ if (cp500_register_uart(cp500, &cp500->uart0_rfb, "rs485-uart",
+ &cp500->devs->uart0_rfb, irq))
+ dev_warn(dev, "Failed to register RFB UART!\n");
+ }
+ if (cp500->devs->uart1_dbg.size &&
+ cp500->devs->uart1_dbg.msix < cp500->msix_num) {
+ int irq = pci_irq_vector(cp500->pci_dev,
+ cp500->devs->uart1_dbg.msix);
+
+ if (cp500_register_uart(cp500, &cp500->uart1_dbg, "rs232-uart",
+ &cp500->devs->uart1_dbg, irq))
+ dev_warn(dev, "Failed to register debug UART!\n");
+ }
+ if (cp500->devs->uart2_si1.size &&
+ cp500->devs->uart2_si1.msix < cp500->msix_num) {
+ int irq = pci_irq_vector(cp500->pci_dev,
+ cp500->devs->uart2_si1.msix);
+
+ if (cp500_register_uart(cp500, &cp500->uart2_si1, "uart",
+ &cp500->devs->uart2_si1, irq))
+ dev_warn(dev, "Failed to register SI1 UART!\n");
+ }
}

static void cp500_unregister_dev(struct auxiliary_device *auxdev)
@@ -694,6 +786,18 @@ static void cp500_unregister_auxiliary_devs(struct cp500 *cp500)
cp500_unregister_dev(&cp500->batt->auxdev);
cp500->batt = NULL;
}
+ if (cp500->uart0_rfb) {
+ cp500_unregister_dev(&cp500->uart0_rfb->auxdev);
+ cp500->uart0_rfb = NULL;
+ }
+ if (cp500->uart1_dbg) {
+ cp500_unregister_dev(&cp500->uart1_dbg->auxdev);
+ cp500->uart1_dbg = NULL;
+ }
+ if (cp500->uart2_si1) {
+ cp500_unregister_dev(&cp500->uart2_si1->auxdev);
+ cp500->uart2_si1 = NULL;
+ }
}

static irqreturn_t cp500_axi_handler(int irq, void *dev)
diff --git a/include/linux/misc/keba.h b/include/linux/misc/keba.h
index ca52716f8437..a81d6fa70851 100644
--- a/include/linux/misc/keba.h
+++ b/include/linux/misc/keba.h
@@ -57,4 +57,16 @@ struct keba_batt_auxdev {
struct resource io;
};

+/**
+ * struct keba_uart_auxdev - KEBA UART auxiliary device
+ * @auxdev: auxiliary device object
+ * @io: address range of UART controller IO memory
+ * @irq: number of UART controller interrupt
+ */
+struct keba_uart_auxdev {
+ struct auxiliary_device auxdev;
+ struct resource io;
+ unsigned int irq;
+};
+
#endif /* _LINUX_MISC_KEBA_H */
--
2.39.2