Hi, On 06/30/2017 12:02 AM, Shilpasri G Bhat wrote: > In P9, OCC (On-Chip-Controller) supports shared memory based > commad-response interface. Within the shared memory there is an OPAL > command buffer and OCC response buffer that can be used to send > inband commands to OCC. This patch adds a platform driver to support > the command/response interface between OCC and the host. > > Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> > Reviewed-by: Cyril Bur <cyril...@gmail.com> > ---
This patch was tested on Witherspoon and below is the snippet of command-response sent to OCC [root@ltc-wspoon4 opal-prd]# ./opal-occ -c 0 -l CSM OCC: Success Sensor limit cleared for CSM [root@ltc-wspoon4 opal-prd]# ./opal-occ -c 0 -l Profiler OCC: Success Sensor limit cleared for Profiler [root@ltc-wspoon4 opal-prd]# ./opal-occ -c 0 -l Job-Scheduler OCC: Success Sensor limit cleared for Job-Scheduler [root@ltc-wspoon4 opal-prd]# ./opal-occ -c 8 -l Job-Scheduler OCC: Success Sensor limit cleared for Job-Scheduler Thanks and Regards, Shilpa > Changes from V5: > - Rebased the opal_call to match the skiboot-master. > Not sure if I need to add the IMC based OPAL call numbers [148-151] so I > have not included them in this patch (which are already upstream in > skiboot but not in kernel) > > The skiboot patch for the interface is posted here: > https://lists.ozlabs.org/pipermail/skiboot/2017-June/008040.html > > arch/powerpc/include/asm/opal-api.h | 41 +++- > arch/powerpc/include/asm/opal.h | 3 + > arch/powerpc/platforms/powernv/Makefile | 2 +- > arch/powerpc/platforms/powernv/opal-occ.c | 303 > +++++++++++++++++++++++++ > arch/powerpc/platforms/powernv/opal-wrappers.S | 1 + > arch/powerpc/platforms/powernv/opal.c | 8 + > 6 files changed, 356 insertions(+), 2 deletions(-) > create mode 100644 arch/powerpc/platforms/powernv/opal-occ.c > > diff --git a/arch/powerpc/include/asm/opal-api.h > b/arch/powerpc/include/asm/opal-api.h > index cb3e624..6876bed 100644 > --- a/arch/powerpc/include/asm/opal-api.h > +++ b/arch/powerpc/include/asm/opal-api.h > @@ -42,6 +42,10 @@ > #define OPAL_I2C_STOP_ERR -24 > #define OPAL_XIVE_PROVISIONING -31 > #define OPAL_XIVE_FREE_ACTIVE -32 > +#define OPAL_OCC_INVALID_STATE -33 > +#define OPAL_OCC_BUSY -34 > +#define OPAL_OCC_CMD_TIMEOUT -35 > +#define OPAL_OCC_RSP_MISMATCH -36 > > /* API Tokens (in r0) */ > #define OPAL_INVALID_CALL -1 > @@ -190,7 +194,8 @@ > #define OPAL_NPU_INIT_CONTEXT 146 > #define OPAL_NPU_DESTROY_CONTEXT 147 > #define OPAL_NPU_MAP_LPAR 148 > -#define OPAL_LAST 148 > +#define OPAL_OCC_COMMAND 152 > +#define OPAL_LAST 152 > > /* Device tree flags */ > > @@ -829,6 +834,40 @@ struct opal_prd_msg_header { > > struct opal_prd_msg; > > +enum occ_cmd { > + OCC_CMD_AMESTER_PASS_THRU = 0, > + OCC_CMD_CLEAR_SENSOR_DATA, > + OCC_CMD_SET_POWER_CAP, > + OCC_CMD_SET_POWER_SHIFTING_RATIO, > + OCC_CMD_SELECT_SENSOR_GROUPS, > + OCC_CMD_LAST > +}; > + > +struct opal_occ_cmd_rsp_msg { > + __be64 cdata; > + __be64 rdata; > + __be16 cdata_size; > + __be16 rdata_size; > + u8 cmd; > + u8 request_id; > + u8 status; > +}; > + > +struct opal_occ_cmd_data { > + __be16 size; > + u8 cmd; > + u8 data[]; > +}; > + > +struct opal_occ_rsp_data { > + __be16 size; > + u8 status; > + u8 data[]; > +}; > + > +#define MAX_OPAL_CMD_DATA_LENGTH 4090 > +#define MAX_OCC_RSP_DATA_LENGTH 8698 > + > #define OCC_RESET 0 > #define OCC_LOAD 1 > #define OCC_THROTTLE 2 > diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h > index 588fb1c..b95d7d5 100644 > --- a/arch/powerpc/include/asm/opal.h > +++ b/arch/powerpc/include/asm/opal.h > @@ -345,6 +345,9 @@ static inline int opal_get_async_rc(struct opal_msg msg) > > void opal_wake_poller(void); > > +int64_t opal_occ_command(int chip_id, struct opal_occ_cmd_rsp_msg *msg, > + int token, bool retry); > + > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_POWERPC_OPAL_H */ > diff --git a/arch/powerpc/platforms/powernv/Makefile > b/arch/powerpc/platforms/powernv/Makefile > index b5d98cb..f5f0902 100644 > --- a/arch/powerpc/platforms/powernv/Makefile > +++ b/arch/powerpc/platforms/powernv/Makefile > @@ -2,7 +2,7 @@ obj-y += setup.o opal-wrappers.o opal.o > opal-async.o idle.o > obj-y += opal-rtc.o opal-nvram.o opal-lpc.o > opal-flash.o > obj-y += rng.o opal-elog.o opal-dump.o > opal-sysparam.o opal-sensor.o > obj-y += opal-msglog.o opal-hmi.o opal-power.o > opal-irqchip.o > -obj-y += opal-kmsg.o > +obj-y += opal-kmsg.o opal-occ.o > > obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o > obj-$(CONFIG_PCI) += pci.o pci-ioda.o npu-dma.o > diff --git a/arch/powerpc/platforms/powernv/opal-occ.c > b/arch/powerpc/platforms/powernv/opal-occ.c > new file mode 100644 > index 0000000..440304f > --- /dev/null > +++ b/arch/powerpc/platforms/powernv/opal-occ.c > @@ -0,0 +1,303 @@ > +/* > + * Copyright IBM Corporation 2017 > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#define pr_fmt(fmt) "opal-occ: " fmt > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/miscdevice.h> > +#include <linux/highmem.h> > +#include <linux/slab.h> > +#include <asm/opal.h> > + > +struct occ { > + struct miscdevice dev; > + struct opal_occ_rsp_data *rsp; > + atomic_t session; > + atomic_t cmd_in_progress; > + atomic_t rsp_consumed; > + int id; > + u8 request_id; > +} *occs; > +static int nr_occs; > + > +static int __send_occ_command(struct opal_occ_cmd_rsp_msg *msg, > + int chip_id, int token, bool retry) > +{ > + struct opal_msg async_msg; > + int rc; > + > + rc = opal_occ_command(chip_id, msg, token, retry); > + if (rc == OPAL_ASYNC_COMPLETION) { > + rc = opal_async_wait_response(token, &async_msg); > + if (rc) { > + pr_devel("Failed to wait for async response %d\n", rc); > + return rc; > + } > + } > + > + return rc ? rc : opal_get_async_rc(async_msg); > +} > + > +static int send_occ_command(struct opal_occ_cmd_rsp_msg *msg, struct occ > *occ) > +{ > + int token, rc; > + > + token = opal_async_get_token_interruptible(); > + if (token < 0) { > + pr_devel("Failed to get the token for OCC command %d (%d)\n", > + msg->cmd, token); > + return token; > + } > + > + msg->request_id = occ->request_id++; > + rc = __send_occ_command(msg, occ->id, token, false); > + > + switch (rc) { > + case OPAL_OCC_CMD_TIMEOUT: > + case OPAL_OCC_RSP_MISMATCH: > + pr_devel("Failed OCC command with %d. Retrying it again\n", rc); > + msg->request_id = occ->request_id++; > + rc = __send_occ_command(msg, occ->id, token, true); > + break; > + default: > + break; > + } > + > + opal_async_release_token(token); > + return opal_error_code(rc); > +} > + > +static int opal_occ_cmd_prepare(struct opal_occ_cmd_data *cmd, struct occ > *occ) > +{ > + struct opal_occ_cmd_rsp_msg msg; > + int rc; > + > + msg.cmd = cmd->cmd; > + msg.cdata = cpu_to_be64(__pa(cmd->data)); > + msg.cdata_size = cpu_to_be16(cmd->size); > + msg.rdata = cpu_to_be64(__pa(occ->rsp->data)); > + > + rc = send_occ_command(&msg, occ); > + if (rc) { > + pr_info("Failed OCC command %d with %d\n", cmd->cmd, rc); > + return rc; > + } > + > + occ->rsp->size = be16_to_cpu(msg.rdata_size); > + occ->rsp->status = msg.status; > + if (occ->rsp->size > MAX_OCC_RSP_DATA_LENGTH) { > + pr_devel("Bigger OCC response size, clipping to %d\n", > + MAX_OCC_RSP_DATA_LENGTH); > + occ->rsp->size = MAX_OCC_RSP_DATA_LENGTH; > + } > + > + atomic_set(&occ->rsp_consumed, 1); > + return rc; > +} > + > +static ssize_t opal_occ_write(struct file *file, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct miscdevice *dev = file->private_data; > + struct occ *occ = container_of(dev, struct occ, dev); > + struct opal_occ_cmd_data *cmd; > + int rc; > + > + if (count < sizeof(*cmd)) > + return -EINVAL; > + > + if (atomic_cmpxchg(&occ->cmd_in_progress, 0, 1)) > + return -EBUSY; > + > + cmd = kmalloc(count, GFP_KERNEL); > + if (!cmd) { > + rc = -ENOMEM; > + goto out; > + } > + > + rc = copy_from_user(cmd, buf, count); > + if (rc) { > + pr_err("Failed to copy OCC command request message\n"); > + rc = -EFAULT; > + goto free_cmd; > + } > + > + if (cmd->size > MAX_OPAL_CMD_DATA_LENGTH) { > + rc = -EINVAL; > + goto free_cmd; > + } > + > + rc = opal_occ_cmd_prepare(cmd, occ); > + if (!rc) > + rc = count; > + > +free_cmd: > + kfree(cmd); > +out: > + atomic_set(&occ->cmd_in_progress, 0); > + return rc; > +} > + > +static ssize_t opal_occ_read(struct file *file, char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct miscdevice *dev = file->private_data; > + struct occ *occ = container_of(dev, struct occ, dev); > + int rc; > + > + if (count < sizeof(*occ->rsp) + occ->rsp->size) > + return -EINVAL; > + > + if (atomic_cmpxchg(&occ->cmd_in_progress, 0, 1)) > + return -EBUSY; > + > + if (!atomic_cmpxchg(&occ->rsp_consumed, 1, 0)) { > + rc = -EBUSY; > + goto out; > + } > + > + rc = copy_to_user((void __user *)buf, occ->rsp, > + sizeof(occ->rsp) + occ->rsp->size); > + if (rc) { > + atomic_set(&occ->rsp_consumed, 1); > + pr_err("Failed to copy OCC response data to user\n"); > + } > + > +out: > + atomic_set(&occ->cmd_in_progress, 0); > + return rc ? rc : sizeof(*occ->rsp) + occ->rsp->size; > +} > + > +static int opal_occ_open(struct inode *inode, struct file *file) > +{ > + struct miscdevice *dev = file->private_data; > + struct occ *occ = container_of(dev, struct occ, dev); > + > + return atomic_cmpxchg(&occ->session, 0, 1) ? -EBUSY : 0; > +} > + > +static int opal_occ_release(struct inode *inode, struct file *file) > +{ > + struct miscdevice *dev = file->private_data; > + struct occ *occ = container_of(dev, struct occ, dev); > + > + atomic_set(&occ->session, 0); > + > + return 0; > +} > + > +static const struct file_operations opal_occ_fops = { > + .open = opal_occ_open, > + .read = opal_occ_read, > + .write = opal_occ_write, > + .release = opal_occ_release, > + .owner = THIS_MODULE, > +}; > + > +#define MAX_POSSIBLE_CHIPS 256 > + > +static int opal_occ_probe(struct platform_device *pdev) > +{ > + unsigned int chip[MAX_POSSIBLE_CHIPS]; > + unsigned int cpu; > + unsigned int prev_chip_id = UINT_MAX; > + int i, rc; > + > + for_each_possible_cpu(cpu) { > + unsigned int id = cpu_to_chip_id(cpu); > + > + if (prev_chip_id != id) { > + int j = nr_occs; > + > + while (--j >= 0) > + if (chip[j] == id) > + continue; > + > + prev_chip_id = id; > + chip[nr_occs++] = id; > + WARN_ON_ONCE(nr_occs >= MAX_POSSIBLE_CHIPS - 1); > + } > + } > + > + occs = kcalloc(nr_occs, sizeof(*occs), GFP_KERNEL); > + if (!occs) > + return -ENOMEM; > + > + for (i = 0; i < nr_occs; i++) { > + char name[10]; > + > + occs[i].id = chip[i]; > + occs[i].dev.minor = MISC_DYNAMIC_MINOR; > + snprintf(name, 10, "occ%d", chip[i]); > + occs[i].dev.name = name; > + occs[i].dev.fops = &opal_occ_fops; > + occs[i].rsp = kmalloc(sizeof(occs[i].rsp) + > + MAX_OCC_RSP_DATA_LENGTH, > + GFP_KERNEL); > + if (!occs[i].rsp) { > + rc = -ENOMEM; > + goto free_occs; > + } > + > + rc = misc_register(&occs[i].dev); > + if (rc) > + goto free_occ_rsp_data; > + } > + > + return 0; > + > +free_occ_rsp_data: > + kfree(occs[i].rsp); > +free_occs: > + while (--i >= 0) { > + kfree(occs[i].rsp); > + misc_deregister(&occs[i].dev); > + } > + kfree(occs); > + > + return rc; > +} > + > +static int opal_occ_remove(struct platform_device *pdev) > +{ > + int i; > + > + for (i = 0; i < nr_occs; i++) { > + kfree(occs[i].rsp); > + misc_deregister(&occs[i].dev); > + } > + > + kfree(occs); > + return 0; > +} > + > +static const struct of_device_id opal_occ_match[] = { > + { .compatible = "ibm,opal-occ-cmd-rsp-interface" }, > + { }, > +}; > + > +static struct platform_driver opal_occ_driver = { > + .driver = { > + .name = "opal-occ", > + .of_match_table = opal_occ_match, > + }, > + .probe = opal_occ_probe, > + .remove = opal_occ_remove, > +}; > + > +module_platform_driver(opal_occ_driver); > + > +MODULE_DESCRIPTION("PowerNV OPAL-OCC driver"); > +MODULE_LICENSE("GPL"); > diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S > b/arch/powerpc/platforms/powernv/opal-wrappers.S > index f620572..e6bf18d 100644 > --- a/arch/powerpc/platforms/powernv/opal-wrappers.S > +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S > @@ -310,3 +310,4 @@ OPAL_CALL(opal_xive_dump, OPAL_XIVE_DUMP); > OPAL_CALL(opal_npu_init_context, OPAL_NPU_INIT_CONTEXT); > OPAL_CALL(opal_npu_destroy_context, OPAL_NPU_DESTROY_CONTEXT); > OPAL_CALL(opal_npu_map_lpar, OPAL_NPU_MAP_LPAR); > +OPAL_CALL(opal_occ_command, OPAL_OCC_COMMAND); > diff --git a/arch/powerpc/platforms/powernv/opal.c > b/arch/powerpc/platforms/powernv/opal.c > index 59684b4..d87c61b 100644 > --- a/arch/powerpc/platforms/powernv/opal.c > +++ b/arch/powerpc/platforms/powernv/opal.c > @@ -815,6 +815,9 @@ static int __init opal_init(void) > opal_pdev_init("ibm,opal-flash"); > opal_pdev_init("ibm,opal-prd"); > > + /* Initialize platform device: OCC_OPAL command-response interface */ > + opal_pdev_init("ibm,opal-occ-cmd-rsp-interface"); > + > /* Initialise platform device: oppanel interface */ > opal_pdev_init("ibm,opal-oppanel"); > > @@ -859,6 +862,7 @@ void opal_shutdown(void) > EXPORT_SYMBOL_GPL(opal_flash_write); > EXPORT_SYMBOL_GPL(opal_flash_erase); > EXPORT_SYMBOL_GPL(opal_prd_msg); > +EXPORT_SYMBOL_GPL(opal_occ_command); > > /* Convert a region of vmalloc memory to an opal sg list */ > struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr, > @@ -937,6 +941,10 @@ int opal_error_code(int rc) > case OPAL_UNSUPPORTED: return -EIO; > case OPAL_HARDWARE: return -EIO; > case OPAL_INTERNAL_ERROR: return -EIO; > + case OPAL_OCC_BUSY: return -EBUSY; > + case OPAL_OCC_INVALID_STATE: > + case OPAL_OCC_CMD_TIMEOUT: > + case OPAL_OCC_RSP_MISMATCH: return -EIO; > default: > pr_err("%s: unexpected OPAL error %d\n", __func__, rc); > return -EIO; >
