This patch adds Loongson-2K BMC IPMI support.
According to the existing design, we use software simulation to
implement the KCS interface registers: Stauts/Command/Data_Out/Data_In.
Also since both host side and BMC side read and write kcs status, I use
fifo pointer to ensure data consistency.
Therefore I made the whole IPMI driver independent.
Co-developed-by: Chong Qiao <qiaoch...@loongson.cn>
Signed-off-by: Chong Qiao <qiaoch...@loongson.cn>
Signed-off-by: Binbin Zhou <zhoubin...@loongson.cn>
---
drivers/char/ipmi/Makefile | 1 +
drivers/char/ipmi/ipmi_si.h | 8 +
drivers/char/ipmi/ipmi_si_intf.c | 3 +
drivers/char/ipmi/ipmi_si_ls2k.c | 250 +++++++++++++++++++++++++++++++
4 files changed, 262 insertions(+)
create mode 100644 drivers/char/ipmi/ipmi_si_ls2k.c
diff --git a/drivers/char/ipmi/Makefile b/drivers/char/ipmi/Makefile
index e0944547c9d0..614be45863b4 100644
--- a/drivers/char/ipmi/Makefile
+++ b/drivers/char/ipmi/Makefile
@@ -7,6 +7,7 @@ ipmi_si-y := ipmi_si_intf.o ipmi_kcs_sm.o ipmi_smic_sm.o
ipmi_bt_sm.o \
ipmi_si_hotmod.o ipmi_si_hardcode.o ipmi_si_platform.o \
ipmi_si_mem_io.o
ipmi_si-$(CONFIG_HAS_IOPORT) += ipmi_si_port_io.o
+ipmi_si-$(CONFIG_LOONGARCH) += ipmi_si_ls2k.o
ipmi_si-$(CONFIG_PCI) += ipmi_si_pci.o
ipmi_si-$(CONFIG_PARISC) += ipmi_si_parisc.o
diff --git a/drivers/char/ipmi/ipmi_si.h b/drivers/char/ipmi/ipmi_si.h
index a7ead2a4c753..0a4af352a42c 100644
--- a/drivers/char/ipmi/ipmi_si.h
+++ b/drivers/char/ipmi/ipmi_si.h
@@ -101,6 +101,14 @@ static inline void ipmi_si_parisc_init(void) { }
static inline void ipmi_si_parisc_shutdown(void) { }
#endif
+#ifdef CONFIG_LOONGARCH
+void ipmi_si_ls2k_init(void);
+void ipmi_si_ls2k_shutdown(void);
+#else
+static inline void ipmi_si_ls2k_init(void) { }
+static inline void ipmi_si_ls2k_shutdown(void) { }
+#endif
+
int ipmi_si_port_setup(struct si_sm_io *io);
int ipmi_si_mem_setup(struct si_sm_io *io);
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index eea23a3b966e..7227bc61be79 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -2108,6 +2108,7 @@ static int __init init_ipmi_si(void)
ipmi_si_pci_init();
ipmi_si_parisc_init();
+ ipmi_si_ls2k_init();
/* We prefer devices with interrupts, but in the case of a machine
with multiple BMCs we assume that there will be several instances
@@ -2292,6 +2293,8 @@ static void cleanup_ipmi_si(void)
ipmi_si_platform_shutdown();
+ ipmi_si_ls2k_shutdown();
+
mutex_lock(&smi_infos_lock);
list_for_each_entry_safe(e, tmp_e, &smi_infos, link)
cleanup_one_si(e);
diff --git a/drivers/char/ipmi/ipmi_si_ls2k.c b/drivers/char/ipmi/ipmi_si_ls2k.c
new file mode 100644
index 000000000000..cb31bb989fca
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_si_ls2k.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for Loongson-2K BMC IPMI
+ *
+ * Copyright (C) 2024 Loongson Technology Corporation Limited.
+ *
+ * Originally written by Chong Qiao <qiaoch...@loongson.cn>
+ * Rewritten for mainline by Binbin Zhou <zhoubin...@loongson.cn>
+ */
+
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include "ipmi_si.h"
+
+#define LS2K_KCS_STS_OBF BIT(0)
+#define LS2K_KCS_STS_IBF BIT(1)
+#define LS2K_KCS_STS_SMS_ATN BIT(2)
+#define LS2K_KCS_STS_CMD BIT(3)
+
+#define LS2K_KCS_DATA_MASK (LS2K_KCS_STS_OBF | LS2K_KCS_STS_IBF |
LS2K_KCS_STS_CMD)
+
+/* Read and write fifo pointers for data consistency. */
+struct ls2k_fifo_flag {
+ u8 ibfh;
+ u8 ibft;
+ u8 obfh;
+ u8 obft;
+};
+
+struct ls2k_kcs_reg {
+ u8 status;
+ u8 data_out;
+ s16 data_in;
+ s16 cmd;
+};
+
+struct ls2k_kcs_data {
+ struct ls2k_fifo_flag fifo;
+ struct ls2k_kcs_reg reg;
+ u8 cmd_data;
+ u8 version;
+ u32 write_req;
+ u32 write_ack;
+ u32 reserved[2];
+};
+
+static void ls2k_set_obf(struct ls2k_kcs_data *ik, u8 sts)
+{
+ ik->reg.status = (ik->reg.status & ~LS2K_KCS_STS_OBF) | (sts & BIT(0));
+}
+
+static void ls2k_set_ibf(struct ls2k_kcs_data *ik, u8 sts)
+{
+ ik->reg.status = (ik->reg.status & ~LS2K_KCS_STS_IBF) | ((sts & BIT(0))
<< 1);
+}
+
+static u8 ls2k_get_ibf(struct ls2k_kcs_data *ik)
+{
+ return (ik->reg.status >> 1) & BIT(0);
+}
+
+static unsigned char intf_sim_inb_v0(struct ls2k_kcs_data *ik,
+ unsigned int offset)
+{
+ u32 inb = 0;
+
+ switch (offset & BIT(0)) {
+ case 0:
+ inb = ik->reg.data_out;
+ ls2k_set_obf(ik, 0);
+ break;
+ case 1:
+ inb = ik->reg.status;
+ break;
+ }
+
+ return inb;
+}
+
+static unsigned char intf_sim_inb_v1(struct ls2k_kcs_data *ik,
+ unsigned int offset)
+{
+ u32 inb = 0;
+ int cmd;
+ bool obf, ibf;
+
+ obf = ik->fifo.obfh != ik->fifo.obft;
+ ibf = ik->fifo.ibfh != ik->fifo.ibft;
+ cmd = ik->cmd_data;
+
+ switch (offset & BIT(0)) {
+ case 0:
+ inb = ik->reg.data_out;
+ ik->fifo.obft = ik->fifo.obfh;
+ break;
+ case 1:
+ inb = ik->reg.status & ~LS2K_KCS_DATA_MASK;
+ inb |= obf | (ibf << 1) | (cmd << 3);
+ break;
+ }
+
+ return inb;
+}
+
+static unsigned char ls2k_mem_inb(const struct si_sm_io *io,
+ unsigned int offset)
+{
+ struct ls2k_kcs_data *ik = io->addr;
+ int inb = 0;
+
+ if (ik->version == 0)
+ inb = intf_sim_inb_v0(ik, offset);
+ else if (ik->version == 1)
+ inb = intf_sim_inb_v1(ik, offset);
+
+ return inb;
+}
+
+static void intf_sim_outb_v0(struct ls2k_kcs_data *ik, unsigned int offset,
+ unsigned char val)
+{
+ if (ls2k_get_ibf(ik))
+ return;
+
+ switch (offset & BIT(0)) {
+ case 0:
+ ik->reg.data_in = val;
+ ik->reg.status &= ~LS2K_KCS_STS_CMD;
+ break;
+
+ case 1:
+ ik->reg.cmd = val;
+ ik->reg.status |= LS2K_KCS_STS_CMD;
+ break;
+ }
+
+ ls2k_set_ibf(ik, 1);
+ ik->write_req++;
+}
+
+static void intf_sim_outb_v1(struct ls2k_kcs_data *ik, unsigned int offset,
+ unsigned char val)
+{
+ if (ik->fifo.ibfh != ik->fifo.ibft)
+ return;
+
+ switch (offset & BIT(0)) {
+ case 0:
+ ik->reg.data_in = val;
+ ik->cmd_data = 0;
+ break;
+
+ case 1:
+ ik->reg.cmd = val;
+ ik->cmd_data = 1;
+ break;
+ }
+
+ ik->fifo.ibfh = !ik->fifo.ibft;
+ ik->write_req++;
+}
+
+static void ls2k_mem_outb(const struct si_sm_io *io, unsigned int offset,
+ unsigned char val)
+{
+ struct ls2k_kcs_data *ik = io->addr;
+
+ if (ik->version == 0)
+ intf_sim_outb_v0(ik, offset, val);
+ else if (ik->version == 1)
+ intf_sim_outb_v1(ik, offset, val);
+}
+
+static void ls2k_mem_cleanup(struct si_sm_io *io)
+{
+ if (io->addr)
+ iounmap(io->addr);
+}
+
+static int ipmi_ls2k_sim_setup(struct si_sm_io *io)
+{
+ io->addr = ioremap(io->addr_data, io->regspacing);
+ if (!io->addr)
+ return -EIO;
+
+ io->inputb = ls2k_mem_inb;
+ io->outputb = ls2k_mem_outb;
+ io->io_cleanup = ls2k_mem_cleanup;
+
+ return 0;
+}
+
+static int ipmi_ls2k_probe(struct platform_device *pdev)
+{
+ struct si_sm_io io;
+
+ dev_info(&pdev->dev, "probing via ls2k platform");
+ memset(&io, 0, sizeof(io));
+
+ io.addr_source = SI_PLATFORM;
+ io.si_type = SI_KCS;
+ io.addr_space = IPMI_MEM_ADDR_SPACE;
+ io.io_setup = ipmi_ls2k_sim_setup;
+ io.addr_data = pdev->resource[0].start;
+ io.regspacing = pdev->resource[0].end - pdev->resource[0].start + 1;
+ io.regsize = DEFAULT_REGSIZE;
+ io.regshift = 0;
+ io.dev = &pdev->dev;
+ io.irq = 0;
+ if (io.irq)
+ io.irq_setup = ipmi_std_irq_setup;
+
+ dev_info(&pdev->dev, "%pR regsize %d spacing %d irq %d\n",
+ &pdev->resource[0], io.regsize, io.regspacing, io.irq);
+
+ return ipmi_si_add_smi(&io);
+}
+
+static void ipmi_ls2k_remove(struct platform_device *pdev)
+{
+ ipmi_si_remove_by_dev(&pdev->dev);
+}
+
+struct platform_driver ipmi_ls2k_platform_driver = {
+ .driver = {
+ .name = "ls2k-ipmi-si",
+ },
+ .probe = ipmi_ls2k_probe,
+ .remove = ipmi_ls2k_remove,
+};
+
+static bool platform_registered;
+void ipmi_si_ls2k_init(void)
+{
+ int rv;
+
+ rv = platform_driver_register(&ipmi_ls2k_platform_driver);
+ if (rv)
+ pr_err("Unable to register driver: %d\n", rv);
+ else
+ platform_registered = true;
+}
+
+void ipmi_si_ls2k_shutdown(void)
+{
+ if (platform_registered)
+ platform_driver_unregister(&ipmi_ls2k_platform_driver);
+}
--
2.43.5
