// SPDX-License-Identifier: GPL-2.0-or-later /* * Driver for the NXP SAA7164 PCIe bridge * * Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com> */ #include <linux/wait.h> #include "saa7164.h" static int saa7164_cmd_alloc_seqno(struct saa7164_dev *dev) { int i, ret = -1; mutex_lock(&dev->lock); for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) { if (dev->cmds[i].inuse == 0) { dev->cmds[i].inuse = 1; dev->cmds[i].signalled = 0; dev->cmds[i].timeout = 0; ret = dev->cmds[i].seqno; break; } } mutex_unlock(&dev->lock); return ret; } static void saa7164_cmd_free_seqno(struct saa7164_dev *dev, u8 seqno) { mutex_lock(&dev->lock); if ((dev->cmds[seqno].inuse == 1) && (dev->cmds[seqno].seqno == seqno)) { dev->cmds[seqno].inuse = 0; dev->cmds[seqno].signalled = 0; dev->cmds[seqno].timeout = 0; } mutex_unlock(&dev->lock); } static void saa7164_cmd_timeout_seqno(struct saa7164_dev *dev, u8 seqno) { mutex_lock(&dev->lock); if ((dev->cmds[seqno].inuse == 1) && (dev->cmds[seqno].seqno == seqno)) { dev->cmds[seqno].timeout = 1; } mutex_unlock(&dev->lock); } static u32 saa7164_cmd_timeout_get(struct saa7164_dev *dev, u8 seqno) { int ret = 0; mutex_lock(&dev->lock); if ((dev->cmds[seqno].inuse == 1) && (dev->cmds[seqno].seqno == seqno)) { ret = dev->cmds[seqno].timeout; } mutex_unlock(&dev->lock); return ret; } /* Commands to the f/w get marshelled to/from this code then onto the PCI * -bus/c running buffer. */ int saa7164_irq_dequeue(struct saa7164_dev *dev) { int ret = SAA_OK, i = 0; u32 timeout; wait_queue_head_t *q = NULL; u8 tmp[512]; dprintk(DBGLVL_CMD, "%s()\n", __func__); /* While any outstand message on the bus exists... */ do { /* Peek the msg bus */ struct tmComResInfo tRsp = { 0, 0, 0, 0, 0, 0 }; ret = saa7164_bus_get(dev, &tRsp, NULL, 1); if (ret != SAA_OK) break; q = &dev->cmds[tRsp.seqno].wait; timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno); dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout); if (!timeout) { dprintk(DBGLVL_CMD, "%s() signalled seqno(%d) (for dequeue)\n", __func__, tRsp.seqno); dev->cmds[tRsp.seqno].signalled = 1; wake_up(q); } else { printk(KERN_ERR "%s() found timed out command on the bus\n", __func__); /* Clean the bus */ ret = saa7164_bus_get(dev, &tRsp, &tmp, 0); printk(KERN_ERR "%s() ret = %x\n", __func__, ret); if (ret == SAA_ERR_EMPTY) /* Someone else already fetched the response */ return SAA_OK; if (ret != SAA_OK) return ret; } /* It's unlikely to have more than 4 or 5 pending messages, * ensure we exit at some point regardless. */ } while (i++ < 32); return ret; } /* Commands to the f/w get marshelled to/from this code then onto the PCI * -bus/c running buffer. */ static int saa7164_cmd_dequeue(struct saa7164_dev *dev) { int ret; u32 timeout; wait_queue_head_t *q = NULL; u8 tmp[512]; dprintk(DBGLVL_CMD, "%s()\n", __func__); while (true) { struct tmComResInfo tRsp = { 0, 0, 0, 0, 0, 0 }; ret = saa7164_bus_get(dev, &tRsp, NULL, 1); if (ret == SAA_ERR_EMPTY) return SAA_OK; if (ret != SAA_OK) return ret; q = &dev->cmds[tRsp.seqno].wait; timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno); dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout); if (timeout) { printk(KERN_ERR "found timed out command on the bus\n"); /* Clean the bus */ ret = saa7164_bus_get(dev, &tRsp, &tmp, 0); printk(KERN_ERR "ret = %x\n", ret); if (ret == SAA_ERR_EMPTY) /* Someone else already fetched the response */ return SAA_OK; if (ret != SAA_OK) return ret; if (tRsp.flags & PVC_CMDFLAG_CONTINUE) printk(KERN_ERR "split response\n"); else saa7164_cmd_free_seqno(dev, tRsp.seqno); printk(KERN_ERR " timeout continue\n"); continue; } dprintk(DBGLVL_CMD, "%s() signalled seqno(%d) (for dequeue)\n", __func__, tRsp.seqno); dev->cmds[tRsp.seqno].signalled = 1; wake_up(q); return SAA_OK; } } static int saa7164_cmd_set(struct saa7164_dev *dev, struct tmComResInfo *msg, void *buf) { struct tmComResBusInfo *bus = &dev->bus; u8 cmd_sent; u16 size, idx; u32 cmds; void *tmp; int ret = -1; if (!msg) { printk(KERN_ERR "%s() !msg\n", __func__); return SAA_ERR_BAD_PARAMETER; } mutex_lock(&dev->cmds[msg->id].lock); size = msg->size; idx = 0; cmds = size / bus->m_wMaxReqSize; if (size % bus->m_wMaxReqSize == 0) cmds -= 1; cmd_sent = 0; /* Split the request into smaller chunks */ for (idx = 0; idx < cmds; idx++) { msg->flags |= SAA_CMDFLAG_CONTINUE; msg->size = bus->m_wMaxReqSize; tmp = buf + idx * bus->m_wMaxReqSize; ret = saa7164_bus_set(dev, msg, tmp); if (ret != SAA_OK) { printk(KERN_ERR "%s() set failed %d\n", __func__, ret); if (cmd_sent) { ret = SAA_ERR_BUSY; goto out; } ret = SAA_ERR_OVERFLOW; goto out; } cmd_sent = 1; } /* If not the last command... */ if (idx != 0) msg->flags &= ~SAA_CMDFLAG_CONTINUE; msg->size = size - idx * bus->m_wMaxReqSize; ret = saa7164_bus_set(dev, msg, buf + idx * bus->m_wMaxReqSize); if (ret != SAA_OK) { printk(KERN_ERR "%s() set last failed %d\n", __func__, ret); if (cmd_sent) { ret = SAA_ERR_BUSY; goto out; } ret = SAA_ERR_OVERFLOW; goto out; } ret = SAA_OK; out: mutex_unlock(&dev->cmds[msg->id].lock); return ret; } /* Wait for a signal event, without holding a mutex. Either return TIMEOUT if * the event never occurred, or SAA_OK if it was signaled during the wait. */ static int saa7164_cmd_wait(struct saa7164_dev *dev, u8 seqno) { wait_queue_head_t *q = NULL; int ret = SAA_BUS_TIMEOUT; unsigned long stamp; int r; if (saa_debug >= 4) saa7164_bus_dump(dev); dprintk(DBGLVL_CMD, "%s(seqno=%d)\n", __func__, seqno); mutex_lock(&dev->lock); if ((dev->cmds[seqno].inuse == 1) && (dev->cmds[seqno].seqno == seqno)) { q = &dev->cmds[seqno].wait; } mutex_unlock(&dev->lock); if (q) { /* If we haven't been signalled we need to wait */ if (dev->cmds[seqno].signalled == 0) { stamp = jiffies; dprintk(DBGLVL_CMD, "%s(seqno=%d) Waiting (signalled=%d)\n", __func__, seqno, dev->cmds[seqno].signalled); /* Wait for signalled to be flagged or timeout */ /* In a highly stressed system this can easily extend * into multiple seconds before the deferred worker * is scheduled, and we're woken up via signal. * We typically are signalled in < 50ms but it can * take MUCH longer. */ wait_event_timeout(*q, dev->cmds[seqno].signalled, (HZ * waitsecs)); r = time_before(jiffies, stamp + (HZ * waitsecs)); if (r) ret = SAA_OK; else saa7164_cmd_timeout_seqno(dev, seqno); dprintk(DBGLVL_CMD, "%s(seqno=%d) Waiting res = %d (signalled=%d)\n", __func__, seqno, r, dev->cmds[seqno].signalled); } else ret = SAA_OK; } else printk(KERN_ERR "%s(seqno=%d) seqno is invalid\n", __func__, seqno); return ret; } void saa7164_cmd_signal(struct saa7164_dev *dev, u8 seqno) { int i; dprintk(DBGLVL_CMD, "%s()\n", __func__); mutex_lock(&dev->lock); for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) { if (dev->cmds[i].inuse == 1) { dprintk(DBGLVL_CMD, "seqno %d inuse, sig = %d, t/out = %d\n", dev->cmds[i].seqno, dev->cmds[i].signalled, dev->cmds[i].timeout); } } for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) { if ((dev->cmds[i].inuse == 1) && ((i == 0) || (dev->cmds[i].signalled) || (dev->cmds[i].timeout))) { dprintk(DBGLVL_CMD, "%s(seqno=%d) calling wake_up\n", __func__, i); dev->cmds[i].signalled = 1; wake_up(&dev->cmds[i].wait); } } mutex_unlock(&dev->lock); } int saa7164_cmd_send(struct saa7164_dev *dev, u8 id, enum tmComResCmd command, u16 controlselector, u16 size, void *buf) { struct tmComResInfo command_t, *pcommand_t; struct tmComResInfo response_t, *presponse_t; u8 errdata[256]; u16 resp_dsize; u16 data_recd; u32 loop; int ret; int safety = 0; dprintk(DBGLVL_CMD, "%s(unitid = %s (%d) , command = 0x%x, sel = 0x%x)\n", __func__, saa7164_unitid_name(dev, id), id, command, controlselector); if ((size == 0) || (buf == NULL)) { printk(KERN_ERR "%s() Invalid param\n", __func__); return SAA_ERR_BAD_PARAMETER; } /* Prepare some basic command/response structures */ memset(&command_t, 0, sizeof(command_t)); memset(&response_t, 0, sizeof(response_t)); pcommand_t = &command_t; presponse_t = &response_t; command_t.id = id; command_t.command = command; command_t.controlselector = controlselector; command_t.size = size; /* Allocate a unique sequence number */ ret = saa7164_cmd_alloc_seqno(dev); if (ret < 0) { printk(KERN_ERR "%s() No free sequences\n", __func__); ret = SAA_ERR_NO_RESOURCES; goto out; } command_t.seqno = (u8)ret; /* Send Command */ resp_dsize = size; pcommand_t->size = size; dprintk(DBGLVL_CMD, "%s() pcommand_t.seqno = %d\n", __func__, pcommand_t->seqno); dprintk(DBGLVL_CMD, "%s() pcommand_t.size = %d\n", __func__, pcommand_t->size); ret = saa7164_cmd_set(dev, pcommand_t, buf); if (ret != SAA_OK) { printk(KERN_ERR "%s() set command failed %d\n", __func__, ret); if (ret != SAA_ERR_BUSY) saa7164_cmd_free_seqno(dev, pcommand_t->seqno); else /* Flag a timeout, because at least one * command was sent */ saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno); goto out; } /* With split responses we have to collect the msgs piece by piece */ data_recd = 0; loop = 1; while (loop) { dprintk(DBGLVL_CMD, "%s() loop\n", __func__); ret = saa7164_cmd_wait(dev, pcommand_t->seqno); dprintk(DBGLVL_CMD, "%s() loop ret = %d\n", __func__, ret); /* if power is down and this is not a power command ... */ if (ret == SAA_BUS_TIMEOUT) { printk(KERN_ERR "Event timed out\n"); saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno); return ret; } if (ret != SAA_OK) { printk(KERN_ERR "spurious error\n"); return ret; } /* Peek response */ ret = saa7164_bus_get(dev, presponse_t, NULL, 1); if (ret == SAA_ERR_EMPTY) { dprintk(4, "%s() SAA_ERR_EMPTY\n", __func__); continue; } if (ret != SAA_OK) { printk(KERN_ERR "peek failed\n"); return ret; } dprintk(DBGLVL_CMD, "%s() presponse_t->seqno = %d\n", __func__, presponse_t->seqno); dprintk(DBGLVL_CMD, "%s() presponse_t->flags = 0x%x\n", __func__, presponse_t->flags); dprintk(DBGLVL_CMD, "%s() presponse_t->size = %d\n", __func__, presponse_t->size); /* Check if the response was for our command */ if (presponse_t->seqno != pcommand_t->seqno) { dprintk(DBGLVL_CMD, "wrong event: seqno = %d, expected seqno = %d, will dequeue regardless\n", presponse_t->seqno, pcommand_t->seqno); ret = saa7164_cmd_dequeue(dev); if (ret != SAA_OK) { printk(KERN_ERR "dequeue failed, ret = %d\n", ret); if (safety++ > 16) { printk(KERN_ERR "dequeue exceeded, safety exit\n"); return SAA_ERR_BUSY; } } continue; } if ((presponse_t->flags & PVC_RESPONSEFLAG_ERROR) != 0) { memset(&errdata[0], 0, sizeof(errdata)); ret = saa7164_bus_get(dev, presponse_t, &errdata[0], 0); if (ret != SAA_OK) { printk(KERN_ERR "get error(2)\n"); return ret; } saa7164_cmd_free_seqno(dev, pcommand_t->seqno); dprintk(DBGLVL_CMD, "%s() errdata %02x%02x%02x%02x\n", __func__, errdata[0], errdata[1], errdata[2], errdata[3]); /* Map error codes */ dprintk(DBGLVL_CMD, "%s() cmd, error code = 0x%x\n", __func__, errdata[0]); switch (errdata[0]) { case PVC_ERRORCODE_INVALID_COMMAND: dprintk(DBGLVL_CMD, "%s() INVALID_COMMAND\n", __func__); ret = SAA_ERR_INVALID_COMMAND; break; case PVC_ERRORCODE_INVALID_DATA: dprintk(DBGLVL_CMD, "%s() INVALID_DATA\n", __func__); ret = SAA_ERR_BAD_PARAMETER; break; case PVC_ERRORCODE_TIMEOUT: dprintk(DBGLVL_CMD, "%s() TIMEOUT\n", __func__); ret = SAA_ERR_TIMEOUT; break; case PVC_ERRORCODE_NAK: dprintk(DBGLVL_CMD, "%s() NAK\n", __func__); ret = SAA_ERR_NULL_PACKET; break; case PVC_ERRORCODE_UNKNOWN: case PVC_ERRORCODE_INVALID_CONTROL: dprintk(DBGLVL_CMD, "%s() UNKNOWN OR INVALID CONTROL\n", __func__); ret = SAA_ERR_NOT_SUPPORTED; break; default: dprintk(DBGLVL_CMD, "%s() UNKNOWN\n", __func__); ret = SAA_ERR_NOT_SUPPORTED; } /* See of other commands are on the bus */ if (saa7164_cmd_dequeue(dev) != SAA_OK) printk(KERN_ERR "dequeue(2) failed\n"); return ret; } /* If response is invalid */ if ((presponse_t->id != pcommand_t->id) || (presponse_t->command != pcommand_t->command) || (presponse_t->controlselector != pcommand_t->controlselector) || (((resp_dsize - data_recd) != presponse_t->size) && !(presponse_t->flags & PVC_CMDFLAG_CONTINUE)) || ((resp_dsize - data_recd) < presponse_t->size)) { /* Invalid */ dprintk(DBGLVL_CMD, "%s() Invalid\n", __func__); ret = saa7164_bus_get(dev, presponse_t, NULL, 0); if (ret != SAA_OK) { printk(KERN_ERR "get failed\n"); return ret; } /* See of other commands are on the bus */ if (saa7164_cmd_dequeue(dev) != SAA_OK) printk(KERN_ERR "dequeue(3) failed\n"); continue; } /* OK, now we're actually getting out correct response */ ret = saa7164_bus_get(dev, presponse_t, buf + data_recd, 0); if (ret != SAA_OK) { printk(KERN_ERR "get failed\n"); return ret; } data_recd = presponse_t->size + data_recd; if (resp_dsize == data_recd) { dprintk(DBGLVL_CMD, "%s() Resp recd\n", __func__); break; } /* See of other commands are on the bus */ if (saa7164_cmd_dequeue(dev) != SAA_OK) printk(KERN_ERR "dequeue(3) failed\n"); continue; } /* (loop) */ /* Release the sequence number allocation */ saa7164_cmd_free_seqno(dev, pcommand_t->seqno); /* if powerdown signal all pending commands */ dprintk(DBGLVL_CMD, "%s() Calling dequeue then exit\n", __func__); /* See of other commands are on the bus */ if (saa7164_cmd_dequeue(dev) != SAA_OK) printk(KERN_ERR "dequeue(4) failed\n"); ret = SAA_OK; out: return ret; }