1b285192aSMauro Carvalho Chehab /* 2b285192aSMauro Carvalho Chehab * Driver for the NXP SAA7164 PCIe bridge 3b285192aSMauro Carvalho Chehab * 4b285192aSMauro Carvalho Chehab * Copyright (c) 2010 Steven Toth <stoth@kernellabs.com> 5b285192aSMauro Carvalho Chehab * 6b285192aSMauro Carvalho Chehab * This program is free software; you can redistribute it and/or modify 7b285192aSMauro Carvalho Chehab * it under the terms of the GNU General Public License as published by 8b285192aSMauro Carvalho Chehab * the Free Software Foundation; either version 2 of the License, or 9b285192aSMauro Carvalho Chehab * (at your option) any later version. 10b285192aSMauro Carvalho Chehab * 11b285192aSMauro Carvalho Chehab * This program is distributed in the hope that it will be useful, 12b285192aSMauro Carvalho Chehab * but WITHOUT ANY WARRANTY; without even the implied warranty of 13b285192aSMauro Carvalho Chehab * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14b285192aSMauro Carvalho Chehab * 15b285192aSMauro Carvalho Chehab * GNU General Public License for more details. 16b285192aSMauro Carvalho Chehab * 17b285192aSMauro Carvalho Chehab * You should have received a copy of the GNU General Public License 18b285192aSMauro Carvalho Chehab * along with this program; if not, write to the Free Software 19b285192aSMauro Carvalho Chehab * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 20b285192aSMauro Carvalho Chehab */ 21b285192aSMauro Carvalho Chehab 22b285192aSMauro Carvalho Chehab #include "saa7164.h" 23b285192aSMauro Carvalho Chehab 24b285192aSMauro Carvalho Chehab /* The message bus to/from the firmware is a ring buffer in PCI address 25b285192aSMauro Carvalho Chehab * space. Establish the defaults. 26b285192aSMauro Carvalho Chehab */ 27b285192aSMauro Carvalho Chehab int saa7164_bus_setup(struct saa7164_dev *dev) 28b285192aSMauro Carvalho Chehab { 29b285192aSMauro Carvalho Chehab struct tmComResBusInfo *b = &dev->bus; 30b285192aSMauro Carvalho Chehab 31b285192aSMauro Carvalho Chehab mutex_init(&b->lock); 32b285192aSMauro Carvalho Chehab 33b285192aSMauro Carvalho Chehab b->Type = TYPE_BUS_PCIe; 34b285192aSMauro Carvalho Chehab b->m_wMaxReqSize = SAA_DEVICE_MAXREQUESTSIZE; 35b285192aSMauro Carvalho Chehab 36*065e1477SHans Verkuil b->m_pdwSetRing = (u8 __iomem *)(dev->bmmio + 37b285192aSMauro Carvalho Chehab ((u32)dev->busdesc.CommandRing)); 38b285192aSMauro Carvalho Chehab 39b285192aSMauro Carvalho Chehab b->m_dwSizeSetRing = SAA_DEVICE_BUFFERBLOCKSIZE; 40b285192aSMauro Carvalho Chehab 41*065e1477SHans Verkuil b->m_pdwGetRing = (u8 __iomem *)(dev->bmmio + 42b285192aSMauro Carvalho Chehab ((u32)dev->busdesc.ResponseRing)); 43b285192aSMauro Carvalho Chehab 44b285192aSMauro Carvalho Chehab b->m_dwSizeGetRing = SAA_DEVICE_BUFFERBLOCKSIZE; 45b285192aSMauro Carvalho Chehab 46b285192aSMauro Carvalho Chehab b->m_dwSetWritePos = ((u32)dev->intfdesc.BARLocation) + 47b285192aSMauro Carvalho Chehab (2 * sizeof(u64)); 48b285192aSMauro Carvalho Chehab b->m_dwSetReadPos = b->m_dwSetWritePos + (1 * sizeof(u32)); 49b285192aSMauro Carvalho Chehab 50b285192aSMauro Carvalho Chehab b->m_dwGetWritePos = b->m_dwSetWritePos + (2 * sizeof(u32)); 51b285192aSMauro Carvalho Chehab b->m_dwGetReadPos = b->m_dwSetWritePos + (3 * sizeof(u32)); 52b285192aSMauro Carvalho Chehab 53b285192aSMauro Carvalho Chehab return 0; 54b285192aSMauro Carvalho Chehab } 55b285192aSMauro Carvalho Chehab 56b285192aSMauro Carvalho Chehab void saa7164_bus_dump(struct saa7164_dev *dev) 57b285192aSMauro Carvalho Chehab { 58b285192aSMauro Carvalho Chehab struct tmComResBusInfo *b = &dev->bus; 59b285192aSMauro Carvalho Chehab 60b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "Dumping the bus structure:\n"); 61b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .type = %d\n", b->Type); 62b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .dev->bmmio = 0x%p\n", dev->bmmio); 63b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_wMaxReqSize = 0x%x\n", b->m_wMaxReqSize); 64b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_pdwSetRing = 0x%p\n", b->m_pdwSetRing); 65b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwSizeSetRing = 0x%x\n", b->m_dwSizeSetRing); 66b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_pdwGetRing = 0x%p\n", b->m_pdwGetRing); 67b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwSizeGetRing = 0x%x\n", b->m_dwSizeGetRing); 68b285192aSMauro Carvalho Chehab 69b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwSetReadPos = 0x%x (0x%08x)\n", 70b285192aSMauro Carvalho Chehab b->m_dwSetReadPos, saa7164_readl(b->m_dwSetReadPos)); 71b285192aSMauro Carvalho Chehab 72b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwSetWritePos = 0x%x (0x%08x)\n", 73b285192aSMauro Carvalho Chehab b->m_dwSetWritePos, saa7164_readl(b->m_dwSetWritePos)); 74b285192aSMauro Carvalho Chehab 75b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwGetReadPos = 0x%x (0x%08x)\n", 76b285192aSMauro Carvalho Chehab b->m_dwGetReadPos, saa7164_readl(b->m_dwGetReadPos)); 77b285192aSMauro Carvalho Chehab 78b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .m_dwGetWritePos = 0x%x (0x%08x)\n", 79b285192aSMauro Carvalho Chehab b->m_dwGetWritePos, saa7164_readl(b->m_dwGetWritePos)); 80b285192aSMauro Carvalho Chehab 81b285192aSMauro Carvalho Chehab } 82b285192aSMauro Carvalho Chehab 83b285192aSMauro Carvalho Chehab /* Intensionally throw a BUG() if the state of the message bus looks corrupt */ 845faf7db8SMauro Carvalho Chehab static void saa7164_bus_verify(struct saa7164_dev *dev) 85b285192aSMauro Carvalho Chehab { 86b285192aSMauro Carvalho Chehab struct tmComResBusInfo *b = &dev->bus; 87b285192aSMauro Carvalho Chehab int bug = 0; 88b285192aSMauro Carvalho Chehab 89b285192aSMauro Carvalho Chehab if (saa7164_readl(b->m_dwSetReadPos) > b->m_dwSizeSetRing) 90b285192aSMauro Carvalho Chehab bug++; 91b285192aSMauro Carvalho Chehab 92b285192aSMauro Carvalho Chehab if (saa7164_readl(b->m_dwSetWritePos) > b->m_dwSizeSetRing) 93b285192aSMauro Carvalho Chehab bug++; 94b285192aSMauro Carvalho Chehab 95b285192aSMauro Carvalho Chehab if (saa7164_readl(b->m_dwGetReadPos) > b->m_dwSizeGetRing) 96b285192aSMauro Carvalho Chehab bug++; 97b285192aSMauro Carvalho Chehab 98b285192aSMauro Carvalho Chehab if (saa7164_readl(b->m_dwGetWritePos) > b->m_dwSizeGetRing) 99b285192aSMauro Carvalho Chehab bug++; 100b285192aSMauro Carvalho Chehab 101b285192aSMauro Carvalho Chehab if (bug) { 102b285192aSMauro Carvalho Chehab saa_debug = 0xffff; /* Ensure we get the bus dump */ 103b285192aSMauro Carvalho Chehab saa7164_bus_dump(dev); 104b285192aSMauro Carvalho Chehab saa_debug = 1024; /* Ensure we get the bus dump */ 105b285192aSMauro Carvalho Chehab BUG(); 106b285192aSMauro Carvalho Chehab } 107b285192aSMauro Carvalho Chehab } 108b285192aSMauro Carvalho Chehab 1095faf7db8SMauro Carvalho Chehab static void saa7164_bus_dumpmsg(struct saa7164_dev *dev, struct tmComResInfo *m, 110b285192aSMauro Carvalho Chehab void *buf) 111b285192aSMauro Carvalho Chehab { 112b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "Dumping msg structure:\n"); 113b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .id = %d\n", m->id); 114b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .flags = 0x%x\n", m->flags); 115b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .size = 0x%x\n", m->size); 116b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .command = 0x%x\n", m->command); 117b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .controlselector = 0x%x\n", m->controlselector); 118b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .seqno = %d\n", m->seqno); 119b285192aSMauro Carvalho Chehab if (buf) 120b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, " .buffer (ignored)\n"); 121b285192aSMauro Carvalho Chehab } 122b285192aSMauro Carvalho Chehab 123b285192aSMauro Carvalho Chehab /* 124b285192aSMauro Carvalho Chehab * Places a command or a response on the bus. The implementation does not 125b285192aSMauro Carvalho Chehab * know if it is a command or a response it just places the data on the 126b285192aSMauro Carvalho Chehab * bus depending on the bus information given in the struct tmComResBusInfo 127b285192aSMauro Carvalho Chehab * structure. If the command or response does not fit into the bus ring 128b285192aSMauro Carvalho Chehab * buffer it will be refused. 129b285192aSMauro Carvalho Chehab * 130b285192aSMauro Carvalho Chehab * Return Value: 131b285192aSMauro Carvalho Chehab * SAA_OK The function executed successfully. 132b285192aSMauro Carvalho Chehab * < 0 One or more members are not initialized. 133b285192aSMauro Carvalho Chehab */ 134b285192aSMauro Carvalho Chehab int saa7164_bus_set(struct saa7164_dev *dev, struct tmComResInfo* msg, 135b285192aSMauro Carvalho Chehab void *buf) 136b285192aSMauro Carvalho Chehab { 137b285192aSMauro Carvalho Chehab struct tmComResBusInfo *bus = &dev->bus; 138b285192aSMauro Carvalho Chehab u32 bytes_to_write, free_write_space, timeout, curr_srp, curr_swp; 139b285192aSMauro Carvalho Chehab u32 new_swp, space_rem; 140b285192aSMauro Carvalho Chehab int ret = SAA_ERR_BAD_PARAMETER; 141*065e1477SHans Verkuil u16 size; 142b285192aSMauro Carvalho Chehab 143b285192aSMauro Carvalho Chehab if (!msg) { 144b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() !msg\n", __func__); 145b285192aSMauro Carvalho Chehab return SAA_ERR_BAD_PARAMETER; 146b285192aSMauro Carvalho Chehab } 147b285192aSMauro Carvalho Chehab 148b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s()\n", __func__); 149b285192aSMauro Carvalho Chehab 150b285192aSMauro Carvalho Chehab saa7164_bus_verify(dev); 151b285192aSMauro Carvalho Chehab 152b285192aSMauro Carvalho Chehab if (msg->size > dev->bus.m_wMaxReqSize) { 153b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() Exceeded dev->bus.m_wMaxReqSize\n", 154b285192aSMauro Carvalho Chehab __func__); 155b285192aSMauro Carvalho Chehab return SAA_ERR_BAD_PARAMETER; 156b285192aSMauro Carvalho Chehab } 157b285192aSMauro Carvalho Chehab 158b285192aSMauro Carvalho Chehab if ((msg->size > 0) && (buf == NULL)) { 159b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() Missing message buffer\n", __func__); 160b285192aSMauro Carvalho Chehab return SAA_ERR_BAD_PARAMETER; 161b285192aSMauro Carvalho Chehab } 162b285192aSMauro Carvalho Chehab 163b285192aSMauro Carvalho Chehab /* Lock the bus from any other access */ 164b285192aSMauro Carvalho Chehab mutex_lock(&bus->lock); 165b285192aSMauro Carvalho Chehab 166b285192aSMauro Carvalho Chehab bytes_to_write = sizeof(*msg) + msg->size; 167b285192aSMauro Carvalho Chehab free_write_space = 0; 168b285192aSMauro Carvalho Chehab timeout = SAA_BUS_TIMEOUT; 169*065e1477SHans Verkuil curr_srp = saa7164_readl(bus->m_dwSetReadPos); 170*065e1477SHans Verkuil curr_swp = saa7164_readl(bus->m_dwSetWritePos); 171b285192aSMauro Carvalho Chehab 172b285192aSMauro Carvalho Chehab /* Deal with ring wrapping issues */ 173b285192aSMauro Carvalho Chehab if (curr_srp > curr_swp) 174b285192aSMauro Carvalho Chehab /* Deal with the wrapped ring */ 175b285192aSMauro Carvalho Chehab free_write_space = curr_srp - curr_swp; 176b285192aSMauro Carvalho Chehab else 177b285192aSMauro Carvalho Chehab /* The ring has not wrapped yet */ 178b285192aSMauro Carvalho Chehab free_write_space = (curr_srp + bus->m_dwSizeSetRing) - curr_swp; 179b285192aSMauro Carvalho Chehab 180b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() bytes_to_write = %d\n", __func__, 181b285192aSMauro Carvalho Chehab bytes_to_write); 182b285192aSMauro Carvalho Chehab 183b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() free_write_space = %d\n", __func__, 184b285192aSMauro Carvalho Chehab free_write_space); 185b285192aSMauro Carvalho Chehab 186b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() curr_srp = %x\n", __func__, curr_srp); 187b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() curr_swp = %x\n", __func__, curr_swp); 188b285192aSMauro Carvalho Chehab 189b285192aSMauro Carvalho Chehab /* Process the msg and write the content onto the bus */ 190b285192aSMauro Carvalho Chehab while (bytes_to_write >= free_write_space) { 191b285192aSMauro Carvalho Chehab 192b285192aSMauro Carvalho Chehab if (timeout-- == 0) { 193b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() bus timeout\n", __func__); 194b285192aSMauro Carvalho Chehab ret = SAA_ERR_NO_RESOURCES; 195b285192aSMauro Carvalho Chehab goto out; 196b285192aSMauro Carvalho Chehab } 197b285192aSMauro Carvalho Chehab 198b285192aSMauro Carvalho Chehab /* TODO: Review this delay, efficient? */ 199b285192aSMauro Carvalho Chehab /* Wait, allowing the hardware fetch time */ 200b285192aSMauro Carvalho Chehab mdelay(1); 201b285192aSMauro Carvalho Chehab 202b285192aSMauro Carvalho Chehab /* Check the space usage again */ 203*065e1477SHans Verkuil curr_srp = saa7164_readl(bus->m_dwSetReadPos); 204b285192aSMauro Carvalho Chehab 205b285192aSMauro Carvalho Chehab /* Deal with ring wrapping issues */ 206b285192aSMauro Carvalho Chehab if (curr_srp > curr_swp) 207b285192aSMauro Carvalho Chehab /* Deal with the wrapped ring */ 208b285192aSMauro Carvalho Chehab free_write_space = curr_srp - curr_swp; 209b285192aSMauro Carvalho Chehab else 210b285192aSMauro Carvalho Chehab /* Read didn't wrap around the buffer */ 211b285192aSMauro Carvalho Chehab free_write_space = (curr_srp + bus->m_dwSizeSetRing) - 212b285192aSMauro Carvalho Chehab curr_swp; 213b285192aSMauro Carvalho Chehab 214b285192aSMauro Carvalho Chehab } 215b285192aSMauro Carvalho Chehab 216b285192aSMauro Carvalho Chehab /* Calculate the new write position */ 217b285192aSMauro Carvalho Chehab new_swp = curr_swp + bytes_to_write; 218b285192aSMauro Carvalho Chehab 219b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() new_swp = %x\n", __func__, new_swp); 220b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() bus->m_dwSizeSetRing = %x\n", __func__, 221b285192aSMauro Carvalho Chehab bus->m_dwSizeSetRing); 222b285192aSMauro Carvalho Chehab 223*065e1477SHans Verkuil /* 224*065e1477SHans Verkuil * Make a copy of msg->size before it is converted to le16 since it is 225*065e1477SHans Verkuil * used in the code below. 226*065e1477SHans Verkuil */ 227*065e1477SHans Verkuil size = msg->size; 228*065e1477SHans Verkuil /* Convert to le16/le32 */ 229*065e1477SHans Verkuil msg->size = (__force u16)cpu_to_le16(msg->size); 230*065e1477SHans Verkuil msg->command = (__force u32)cpu_to_le32(msg->command); 231*065e1477SHans Verkuil msg->controlselector = (__force u16)cpu_to_le16(msg->controlselector); 232*065e1477SHans Verkuil 233b285192aSMauro Carvalho Chehab /* Mental Note: line 462 tmmhComResBusPCIe.cpp */ 234b285192aSMauro Carvalho Chehab 235b285192aSMauro Carvalho Chehab /* Check if we're going to wrap again */ 236b285192aSMauro Carvalho Chehab if (new_swp > bus->m_dwSizeSetRing) { 237b285192aSMauro Carvalho Chehab 238b285192aSMauro Carvalho Chehab /* Ring wraps */ 239b285192aSMauro Carvalho Chehab new_swp -= bus->m_dwSizeSetRing; 240b285192aSMauro Carvalho Chehab 241b285192aSMauro Carvalho Chehab space_rem = bus->m_dwSizeSetRing - curr_swp; 242b285192aSMauro Carvalho Chehab 243b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() space_rem = %x\n", __func__, 244b285192aSMauro Carvalho Chehab space_rem); 245b285192aSMauro Carvalho Chehab 246b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() sizeof(*msg) = %d\n", __func__, 247b285192aSMauro Carvalho Chehab (u32)sizeof(*msg)); 248b285192aSMauro Carvalho Chehab 249b285192aSMauro Carvalho Chehab if (space_rem < sizeof(*msg)) { 250b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() tr4\n", __func__); 251b285192aSMauro Carvalho Chehab 252b285192aSMauro Carvalho Chehab /* Split the msg into pieces as the ring wraps */ 253*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, space_rem); 254*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing, (u8 *)msg + space_rem, 255b285192aSMauro Carvalho Chehab sizeof(*msg) - space_rem); 256b285192aSMauro Carvalho Chehab 257*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + sizeof(*msg) - space_rem, 258*065e1477SHans Verkuil buf, size); 259b285192aSMauro Carvalho Chehab 260b285192aSMauro Carvalho Chehab } else if (space_rem == sizeof(*msg)) { 261b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() tr5\n", __func__); 262b285192aSMauro Carvalho Chehab 263b285192aSMauro Carvalho Chehab /* Additional data at the beginning of the ring */ 264*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); 265*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing, buf, size); 266b285192aSMauro Carvalho Chehab 267b285192aSMauro Carvalho Chehab } else { 268b285192aSMauro Carvalho Chehab /* Additional data wraps around the ring */ 269*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); 270*065e1477SHans Verkuil if (size > 0) { 271*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp + 272b285192aSMauro Carvalho Chehab sizeof(*msg), buf, space_rem - 273b285192aSMauro Carvalho Chehab sizeof(*msg)); 274*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing, (u8 *)buf + 275b285192aSMauro Carvalho Chehab space_rem - sizeof(*msg), 276b285192aSMauro Carvalho Chehab bytes_to_write - space_rem); 277b285192aSMauro Carvalho Chehab } 278b285192aSMauro Carvalho Chehab 279b285192aSMauro Carvalho Chehab } 280b285192aSMauro Carvalho Chehab 281b285192aSMauro Carvalho Chehab } /* (new_swp > bus->m_dwSizeSetRing) */ 282b285192aSMauro Carvalho Chehab else { 283b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() tr6\n", __func__); 284b285192aSMauro Carvalho Chehab 285b285192aSMauro Carvalho Chehab /* The ring buffer doesn't wrap, two simple copies */ 286*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); 287*065e1477SHans Verkuil memcpy_toio(bus->m_pdwSetRing + curr_swp + sizeof(*msg), buf, 288*065e1477SHans Verkuil size); 289b285192aSMauro Carvalho Chehab } 290b285192aSMauro Carvalho Chehab 291b285192aSMauro Carvalho Chehab dprintk(DBGLVL_BUS, "%s() new_swp = %x\n", __func__, new_swp); 292b285192aSMauro Carvalho Chehab 293b285192aSMauro Carvalho Chehab /* Update the bus write position */ 294*065e1477SHans Verkuil saa7164_writel(bus->m_dwSetWritePos, new_swp); 295*065e1477SHans Verkuil 296*065e1477SHans Verkuil /* Convert back to cpu after writing the msg to the ringbuffer. */ 297*065e1477SHans Verkuil msg->size = le16_to_cpu((__force __le16)msg->size); 298*065e1477SHans Verkuil msg->command = le32_to_cpu((__force __le32)msg->command); 299*065e1477SHans Verkuil msg->controlselector = le16_to_cpu((__force __le16)msg->controlselector); 300b285192aSMauro Carvalho Chehab ret = SAA_OK; 301b285192aSMauro Carvalho Chehab 302b285192aSMauro Carvalho Chehab out: 303b285192aSMauro Carvalho Chehab saa7164_bus_dump(dev); 304b285192aSMauro Carvalho Chehab mutex_unlock(&bus->lock); 305b285192aSMauro Carvalho Chehab saa7164_bus_verify(dev); 306b285192aSMauro Carvalho Chehab return ret; 307b285192aSMauro Carvalho Chehab } 308b285192aSMauro Carvalho Chehab 309b285192aSMauro Carvalho Chehab /* 310b285192aSMauro Carvalho Chehab * Receive a command or a response from the bus. The implementation does not 311b285192aSMauro Carvalho Chehab * know if it is a command or a response it simply dequeues the data, 312b285192aSMauro Carvalho Chehab * depending on the bus information given in the struct tmComResBusInfo 313b285192aSMauro Carvalho Chehab * structure. 314b285192aSMauro Carvalho Chehab * 315b285192aSMauro Carvalho Chehab * Return Value: 316b285192aSMauro Carvalho Chehab * 0 The function executed successfully. 317b285192aSMauro Carvalho Chehab * < 0 One or more members are not initialized. 318b285192aSMauro Carvalho Chehab */ 319b285192aSMauro Carvalho Chehab int saa7164_bus_get(struct saa7164_dev *dev, struct tmComResInfo* msg, 320b285192aSMauro Carvalho Chehab void *buf, int peekonly) 321b285192aSMauro Carvalho Chehab { 322b285192aSMauro Carvalho Chehab struct tmComResBusInfo *bus = &dev->bus; 323b285192aSMauro Carvalho Chehab u32 bytes_to_read, write_distance, curr_grp, curr_gwp, 324b285192aSMauro Carvalho Chehab new_grp, buf_size, space_rem; 325b285192aSMauro Carvalho Chehab struct tmComResInfo msg_tmp; 326b285192aSMauro Carvalho Chehab int ret = SAA_ERR_BAD_PARAMETER; 327b285192aSMauro Carvalho Chehab 328b285192aSMauro Carvalho Chehab saa7164_bus_verify(dev); 329b285192aSMauro Carvalho Chehab 330b285192aSMauro Carvalho Chehab if (msg == NULL) 331b285192aSMauro Carvalho Chehab return ret; 332b285192aSMauro Carvalho Chehab 333b285192aSMauro Carvalho Chehab if (msg->size > dev->bus.m_wMaxReqSize) { 334b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() Exceeded dev->bus.m_wMaxReqSize\n", 335b285192aSMauro Carvalho Chehab __func__); 336b285192aSMauro Carvalho Chehab return ret; 337b285192aSMauro Carvalho Chehab } 338b285192aSMauro Carvalho Chehab 339b285192aSMauro Carvalho Chehab if ((peekonly == 0) && (msg->size > 0) && (buf == NULL)) { 340b285192aSMauro Carvalho Chehab printk(KERN_ERR 341b285192aSMauro Carvalho Chehab "%s() Missing msg buf, size should be %d bytes\n", 342b285192aSMauro Carvalho Chehab __func__, msg->size); 343b285192aSMauro Carvalho Chehab return ret; 344b285192aSMauro Carvalho Chehab } 345b285192aSMauro Carvalho Chehab 346b285192aSMauro Carvalho Chehab mutex_lock(&bus->lock); 347b285192aSMauro Carvalho Chehab 348b285192aSMauro Carvalho Chehab /* Peek the bus to see if a msg exists, if it's not what we're expecting 349b285192aSMauro Carvalho Chehab * then return cleanly else read the message from the bus. 350b285192aSMauro Carvalho Chehab */ 351*065e1477SHans Verkuil curr_gwp = saa7164_readl(bus->m_dwGetWritePos); 352*065e1477SHans Verkuil curr_grp = saa7164_readl(bus->m_dwGetReadPos); 353b285192aSMauro Carvalho Chehab 354b285192aSMauro Carvalho Chehab if (curr_gwp == curr_grp) { 355b285192aSMauro Carvalho Chehab ret = SAA_ERR_EMPTY; 356b285192aSMauro Carvalho Chehab goto out; 357b285192aSMauro Carvalho Chehab } 358b285192aSMauro Carvalho Chehab 359b285192aSMauro Carvalho Chehab bytes_to_read = sizeof(*msg); 360b285192aSMauro Carvalho Chehab 361b285192aSMauro Carvalho Chehab /* Calculate write distance to current read position */ 362b285192aSMauro Carvalho Chehab write_distance = 0; 363b285192aSMauro Carvalho Chehab if (curr_gwp >= curr_grp) 364b285192aSMauro Carvalho Chehab /* Write doesn't wrap around the ring */ 365b285192aSMauro Carvalho Chehab write_distance = curr_gwp - curr_grp; 366b285192aSMauro Carvalho Chehab else 367b285192aSMauro Carvalho Chehab /* Write wraps around the ring */ 368b285192aSMauro Carvalho Chehab write_distance = curr_gwp + bus->m_dwSizeGetRing - curr_grp; 369b285192aSMauro Carvalho Chehab 370b285192aSMauro Carvalho Chehab if (bytes_to_read > write_distance) { 371b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() No message/response found\n", __func__); 372b285192aSMauro Carvalho Chehab ret = SAA_ERR_INVALID_COMMAND; 373b285192aSMauro Carvalho Chehab goto out; 374b285192aSMauro Carvalho Chehab } 375b285192aSMauro Carvalho Chehab 376b285192aSMauro Carvalho Chehab /* Calculate the new read position */ 377b285192aSMauro Carvalho Chehab new_grp = curr_grp + bytes_to_read; 378b285192aSMauro Carvalho Chehab if (new_grp > bus->m_dwSizeGetRing) { 379b285192aSMauro Carvalho Chehab 380b285192aSMauro Carvalho Chehab /* Ring wraps */ 381b285192aSMauro Carvalho Chehab new_grp -= bus->m_dwSizeGetRing; 382b285192aSMauro Carvalho Chehab space_rem = bus->m_dwSizeGetRing - curr_grp; 383b285192aSMauro Carvalho Chehab 384*065e1477SHans Verkuil memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, space_rem); 385*065e1477SHans Verkuil memcpy_fromio((u8 *)&msg_tmp + space_rem, bus->m_pdwGetRing, 386b285192aSMauro Carvalho Chehab bytes_to_read - space_rem); 387b285192aSMauro Carvalho Chehab 388b285192aSMauro Carvalho Chehab } else { 389b285192aSMauro Carvalho Chehab /* No wrapping */ 390*065e1477SHans Verkuil memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, bytes_to_read); 391b285192aSMauro Carvalho Chehab } 392*065e1477SHans Verkuil /* Convert from little endian to CPU */ 393*065e1477SHans Verkuil msg_tmp.size = le16_to_cpu((__force __le16)msg_tmp.size); 394*065e1477SHans Verkuil msg_tmp.command = le32_to_cpu((__force __le32)msg_tmp.command); 395*065e1477SHans Verkuil msg_tmp.controlselector = le16_to_cpu((__force __le16)msg_tmp.controlselector); 396b285192aSMauro Carvalho Chehab 397b285192aSMauro Carvalho Chehab /* No need to update the read positions, because this was a peek */ 398b285192aSMauro Carvalho Chehab /* If the caller specifically want to peek, return */ 399b285192aSMauro Carvalho Chehab if (peekonly) { 400b285192aSMauro Carvalho Chehab memcpy(msg, &msg_tmp, sizeof(*msg)); 401b285192aSMauro Carvalho Chehab goto peekout; 402b285192aSMauro Carvalho Chehab } 403b285192aSMauro Carvalho Chehab 404b285192aSMauro Carvalho Chehab /* Check if the command/response matches what is expected */ 405b285192aSMauro Carvalho Chehab if ((msg_tmp.id != msg->id) || (msg_tmp.command != msg->command) || 406b285192aSMauro Carvalho Chehab (msg_tmp.controlselector != msg->controlselector) || 407b285192aSMauro Carvalho Chehab (msg_tmp.seqno != msg->seqno) || (msg_tmp.size != msg->size)) { 408b285192aSMauro Carvalho Chehab 409b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() Unexpected msg miss-match\n", __func__); 410b285192aSMauro Carvalho Chehab saa7164_bus_dumpmsg(dev, msg, buf); 411b285192aSMauro Carvalho Chehab saa7164_bus_dumpmsg(dev, &msg_tmp, NULL); 412b285192aSMauro Carvalho Chehab ret = SAA_ERR_INVALID_COMMAND; 413b285192aSMauro Carvalho Chehab goto out; 414b285192aSMauro Carvalho Chehab } 415b285192aSMauro Carvalho Chehab 416b285192aSMauro Carvalho Chehab /* Get the actual command and response from the bus */ 417b285192aSMauro Carvalho Chehab buf_size = msg->size; 418b285192aSMauro Carvalho Chehab 419b285192aSMauro Carvalho Chehab bytes_to_read = sizeof(*msg) + msg->size; 420b285192aSMauro Carvalho Chehab /* Calculate write distance to current read position */ 421b285192aSMauro Carvalho Chehab write_distance = 0; 422b285192aSMauro Carvalho Chehab if (curr_gwp >= curr_grp) 423b285192aSMauro Carvalho Chehab /* Write doesn't wrap around the ring */ 424b285192aSMauro Carvalho Chehab write_distance = curr_gwp - curr_grp; 425b285192aSMauro Carvalho Chehab else 426b285192aSMauro Carvalho Chehab /* Write wraps around the ring */ 427b285192aSMauro Carvalho Chehab write_distance = curr_gwp + bus->m_dwSizeGetRing - curr_grp; 428b285192aSMauro Carvalho Chehab 429b285192aSMauro Carvalho Chehab if (bytes_to_read > write_distance) { 430b285192aSMauro Carvalho Chehab printk(KERN_ERR "%s() Invalid bus state, missing msg " 431b285192aSMauro Carvalho Chehab "or mangled ring, faulty H/W / bad code?\n", __func__); 432b285192aSMauro Carvalho Chehab ret = SAA_ERR_INVALID_COMMAND; 433b285192aSMauro Carvalho Chehab goto out; 434b285192aSMauro Carvalho Chehab } 435b285192aSMauro Carvalho Chehab 436b285192aSMauro Carvalho Chehab /* Calculate the new read position */ 437b285192aSMauro Carvalho Chehab new_grp = curr_grp + bytes_to_read; 438b285192aSMauro Carvalho Chehab if (new_grp > bus->m_dwSizeGetRing) { 439b285192aSMauro Carvalho Chehab 440b285192aSMauro Carvalho Chehab /* Ring wraps */ 441b285192aSMauro Carvalho Chehab new_grp -= bus->m_dwSizeGetRing; 442b285192aSMauro Carvalho Chehab space_rem = bus->m_dwSizeGetRing - curr_grp; 443b285192aSMauro Carvalho Chehab 444b285192aSMauro Carvalho Chehab if (space_rem < sizeof(*msg)) { 445b285192aSMauro Carvalho Chehab /* msg wraps around the ring */ 446*065e1477SHans Verkuil memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, space_rem); 447*065e1477SHans Verkuil memcpy_fromio((u8 *)msg + space_rem, bus->m_pdwGetRing, 448b285192aSMauro Carvalho Chehab sizeof(*msg) - space_rem); 449b285192aSMauro Carvalho Chehab if (buf) 450*065e1477SHans Verkuil memcpy_fromio(buf, bus->m_pdwGetRing + sizeof(*msg) - 451b285192aSMauro Carvalho Chehab space_rem, buf_size); 452b285192aSMauro Carvalho Chehab 453b285192aSMauro Carvalho Chehab } else if (space_rem == sizeof(*msg)) { 454*065e1477SHans Verkuil memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg)); 455b285192aSMauro Carvalho Chehab if (buf) 456*065e1477SHans Verkuil memcpy_fromio(buf, bus->m_pdwGetRing, buf_size); 457b285192aSMauro Carvalho Chehab } else { 458b285192aSMauro Carvalho Chehab /* Additional data wraps around the ring */ 459*065e1477SHans Verkuil memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg)); 460b285192aSMauro Carvalho Chehab if (buf) { 461*065e1477SHans Verkuil memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + 462b285192aSMauro Carvalho Chehab sizeof(*msg), space_rem - sizeof(*msg)); 463*065e1477SHans Verkuil memcpy_fromio(buf + space_rem - sizeof(*msg), 464b285192aSMauro Carvalho Chehab bus->m_pdwGetRing, bytes_to_read - 465b285192aSMauro Carvalho Chehab space_rem); 466b285192aSMauro Carvalho Chehab } 467b285192aSMauro Carvalho Chehab 468b285192aSMauro Carvalho Chehab } 469b285192aSMauro Carvalho Chehab 470b285192aSMauro Carvalho Chehab } else { 471b285192aSMauro Carvalho Chehab /* No wrapping */ 472*065e1477SHans Verkuil memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg)); 473b285192aSMauro Carvalho Chehab if (buf) 474*065e1477SHans Verkuil memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg), 475b285192aSMauro Carvalho Chehab buf_size); 476b285192aSMauro Carvalho Chehab } 477*065e1477SHans Verkuil /* Convert from little endian to CPU */ 478*065e1477SHans Verkuil msg->size = le16_to_cpu((__force __le16)msg->size); 479*065e1477SHans Verkuil msg->command = le32_to_cpu((__force __le32)msg->command); 480*065e1477SHans Verkuil msg->controlselector = le16_to_cpu((__force __le16)msg->controlselector); 481b285192aSMauro Carvalho Chehab 482b285192aSMauro Carvalho Chehab /* Update the read positions, adjusting the ring */ 483*065e1477SHans Verkuil saa7164_writel(bus->m_dwGetReadPos, new_grp); 484b285192aSMauro Carvalho Chehab 485b285192aSMauro Carvalho Chehab peekout: 486b285192aSMauro Carvalho Chehab ret = SAA_OK; 487b285192aSMauro Carvalho Chehab out: 488b285192aSMauro Carvalho Chehab mutex_unlock(&bus->lock); 489b285192aSMauro Carvalho Chehab saa7164_bus_verify(dev); 490b285192aSMauro Carvalho Chehab return ret; 491b285192aSMauro Carvalho Chehab } 492b285192aSMauro Carvalho Chehab 493