brcmfmac: add sdio sg list support

Add scatter gather list support for better rx glom performance.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 137 insertions, 174 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh.c
index 32a205e0b063..3f8e69c29146 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh.c
@@ -22,9 +22,11 @@
 #include <linux/pci_ids.h>
 #include <linux/sched.h>
 #include <linux/completion.h>
+#include <linux/scatterlist.h>
 #include <linux/mmc/sdio.h>
 #include <linux/mmc/sdio_func.h>
 #include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
 #include <linux/platform_data/brcmfmac-sdio.h>
 
 #include <defs.h>
@@ -316,34 +318,138 @@ void brcmf_sdio_regwl(struct brcmf_sdio_dev *sdiodev, u32 addr,
  * caller has already been padded and aligned.
  */
 static int brcmf_sdio_buffrw(struct brcmf_sdio_dev *sdiodev, uint fn,
-                             bool write, u32 addr, struct sk_buff *pkt)
+                             bool write, u32 addr, struct sk_buff_head *pktlist)
 {
-        uint len;
+        unsigned int req_sz, func_blk_sz, sg_cnt, sg_data_sz, pkt_offset;
+        unsigned int max_blks, max_req_sz;
+        unsigned short max_seg_sz, seg_sz;
+        unsigned char *pkt_data;
+        struct sk_buff *pkt_next = NULL;
+        struct mmc_request mmc_req;
+        struct mmc_command mmc_cmd;
+        struct mmc_data mmc_dat;
+        struct sg_table st;
+        struct scatterlist *sgl;
+        struct mmc_host *host;
+        int ret = 0;
+
+        if (!pktlist->qlen)
+                return -EINVAL;
 
         brcmf_pm_resume_wait(sdiodev, &sdiodev->request_buffer_wait);
         if (brcmf_pm_resume_error(sdiodev))
                 return -EIO;
 
         /* Single skb use the standard mmc interface */
-        if (!pkt->next) {
-                len = pkt->len + 3;
-                len &= (uint)~3;
+        if (pktlist->qlen == 1) {
+                pkt_next = pktlist->next;
+                req_sz = pkt_next->len + 3;
+                req_sz &= (uint)~3;
 
                 if (write)
                         return sdio_memcpy_toio(sdiodev->func[fn], addr,
-                                                ((u8 *)(pkt->data)), len);
+                                                ((u8 *)(pkt_next->data)),
+                                                req_sz);
                 else if (fn == 1)
                         return sdio_memcpy_fromio(sdiodev->func[fn],
-                                                  ((u8 *)(pkt->data)), addr,
-                                                  len);
+                                                  ((u8 *)(pkt_next->data)),
+                                                  addr, req_sz);
                 else
                         /* function 2 read is FIFO operation */
                         return sdio_readsb(sdiodev->func[fn],
-                                           ((u8 *)(pkt->data)), addr, len);
+                                           ((u8 *)(pkt_next->data)), addr,
+                                           req_sz);
         }
 
-        brcmf_err("skb chain is not supported yet.\n");
-        return -EOPNOTSUPP;
+        host = sdiodev->func[fn]->card->host;
+        func_blk_sz = sdiodev->func[fn]->cur_blksize;
+        /* Blocks per command is limited by host count, host transfer
+         * size and the maximum for IO_RW_EXTENDED of 511 blocks.
+         */
+        max_blks = min_t(unsigned int, host->max_blk_count, 511u);
+        max_req_sz = min_t(unsigned int, host->max_req_size,
+                           max_blks * func_blk_sz);
+        max_seg_sz = min_t(unsigned short, host->max_segs, SG_MAX_SINGLE_ALLOC);
+        max_seg_sz = min_t(unsigned short, max_seg_sz, pktlist->qlen);
+        seg_sz = pktlist->qlen;
+        pkt_offset = 0;
+        pkt_next = pktlist->next;
+
+        if (sg_alloc_table(&st, max_seg_sz, GFP_KERNEL))
+                return -ENOMEM;
+
+        while (seg_sz) {
+                req_sz = 0;
+                sg_cnt = 0;
+                memset(&mmc_req, 0, sizeof(struct mmc_request));
+                memset(&mmc_cmd, 0, sizeof(struct mmc_command));
+                memset(&mmc_dat, 0, sizeof(struct mmc_data));
+                sgl = st.sgl;
+                /* prep sg table */
+                while (pkt_next != (struct sk_buff *)pktlist) {
+                        pkt_data = pkt_next->data + pkt_offset;
+                        sg_data_sz = pkt_next->len - pkt_offset;
+                        if (sg_data_sz > host->max_seg_size)
+                                sg_data_sz = host->max_seg_size;
+                        if (sg_data_sz > max_req_sz - req_sz)
+                                sg_data_sz = max_req_sz - req_sz;
+
+                        sg_set_buf(sgl, pkt_data, sg_data_sz);
+
+                        sg_cnt++;
+                        sgl = sg_next(sgl);
+                        req_sz += sg_data_sz;
+                        pkt_offset += sg_data_sz;
+                        if (pkt_offset == pkt_next->len) {
+                                pkt_offset = 0;
+                                pkt_next = pkt_next->next;
+                        }
+
+                        if (req_sz >= max_req_sz || sg_cnt >= max_seg_sz)
+                                break;
+                }
+                seg_sz -= sg_cnt;
+
+                if (req_sz % func_blk_sz != 0) {
+                        brcmf_err("sg request length %u is not %u aligned\n",
+                                  req_sz, func_blk_sz);
+                        sg_free_table(&st);
+                        return -ENOTBLK;
+                }
+                mmc_dat.sg = st.sgl;
+                mmc_dat.sg_len = sg_cnt;
+                mmc_dat.blksz = func_blk_sz;
+                mmc_dat.blocks = req_sz / func_blk_sz;
+                mmc_dat.flags = write ? MMC_DATA_WRITE : MMC_DATA_READ;
+                mmc_cmd.opcode = SD_IO_RW_EXTENDED;
+                mmc_cmd.arg = write ? 1<<31 : 0;        /* write flag  */
+                mmc_cmd.arg |= (fn & 0x7) << 28;        /* SDIO func num */
+                mmc_cmd.arg |= 1<<27;                   /* block mode */
+                /* incrementing addr for function 1 */
+                mmc_cmd.arg |= (fn == 1) ? 1<<26 : 0;
+                mmc_cmd.arg |= (addr & 0x1FFFF) << 9;   /* address */
+                mmc_cmd.arg |= mmc_dat.blocks & 0x1FF;  /* block count */
+                mmc_cmd.flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_ADTC;
+                mmc_req.cmd = &mmc_cmd;
+                mmc_req.data = &mmc_dat;
+                if (fn == 1)
+                        addr += req_sz;
+
+                mmc_set_data_timeout(&mmc_dat, sdiodev->func[fn]->card);
+                mmc_wait_for_req(host, &mmc_req);
+
+                ret = mmc_cmd.error ? mmc_cmd.error : mmc_dat.error;
+                if (ret != 0) {
+                        brcmf_err("CMD53 sg block %s failed %d\n",
+                                  write ? "write" : "read", ret);
+                        ret = -EIO;
+                        break;
+                }
+        }
+
+        sg_free_table(&st);
+
+        return ret;
 }
 
 static int brcmf_sdcard_recv_prepare(struct brcmf_sdio_dev *sdiodev, uint fn,
@@ -400,6 +506,7 @@ brcmf_sdcard_recv_pkt(struct brcmf_sdio_dev *sdiodev, u32 addr, uint fn,
 {
         uint width;
         int err = 0;
+        struct sk_buff_head pkt_list;
 
         brcmf_dbg(SDIO, "fun = %d, addr = 0x%x, size = %d\n",
                   fn, addr, pkt->len);
@@ -409,7 +516,10 @@ brcmf_sdcard_recv_pkt(struct brcmf_sdio_dev *sdiodev, u32 addr, uint fn,
         if (err)
                 goto done;
 
-        err = brcmf_sdio_buffrw(sdiodev, fn, false, addr, pkt);
+        skb_queue_head_init(&pkt_list);
+        skb_queue_tail(&pkt_list, pkt);
+        err = brcmf_sdio_buffrw(sdiodev, fn, false, addr, &pkt_list);
+        skb_dequeue_tail(&pkt_list);
 
 done:
         return err;
@@ -431,8 +541,7 @@ int brcmf_sdcard_recv_chain(struct brcmf_sdio_dev *sdiodev, u32 addr, uint fn,
                 goto done;
 
         incr_fix = (flags & SDIO_REQ_FIXED) ? SDIOH_DATA_FIX : SDIOH_DATA_INC;
-        err = brcmf_sdioh_request_chain(sdiodev, incr_fix, SDIOH_READ, fn, addr,
-                                        pktq);
+        err = brcmf_sdio_buffrw(sdiodev, fn, false, addr, pktq);
 
 done:
         return err;
@@ -467,6 +576,7 @@ brcmf_sdcard_send_pkt(struct brcmf_sdio_dev *sdiodev, u32 addr, uint fn,
         uint width;
         uint bar0 = addr & ~SBSDIO_SB_OFT_ADDR_MASK;
         int err = 0;
+        struct sk_buff_head pkt_list;
 
         brcmf_dbg(SDIO, "fun = %d, addr = 0x%x, size = %d\n",
                   fn, addr, pkt->len);
@@ -489,7 +599,10 @@ brcmf_sdcard_send_pkt(struct brcmf_sdio_dev *sdiodev, u32 addr, uint fn,
         if (width == 4)
                 addr |= SBSDIO_SB_ACCESS_2_4B_FLAG;
 
-        err = brcmf_sdio_buffrw(sdiodev, fn, true, addr, pkt);
+        skb_queue_head_init(&pkt_list);
+        skb_queue_tail(&pkt_list, pkt);
+        err = brcmf_sdio_buffrw(sdiodev, fn, true, addr, &pkt_list);
+        skb_dequeue_tail(&pkt_list);
 
 done:
         return err;
@@ -503,6 +616,7 @@ brcmf_sdio_ramrw(struct brcmf_sdio_dev *sdiodev, bool write, u32 address,
         struct sk_buff *pkt;
         u32 sdaddr;
         uint dsize;
+        struct sk_buff_head pkt_list;
 
         dsize = min_t(uint, SBSDIO_SB_OFT_ADDR_LIMIT, size);
         pkt = dev_alloc_skb(dsize);
@@ -511,6 +625,7 @@ brcmf_sdio_ramrw(struct brcmf_sdio_dev *sdiodev, bool write, u32 address,
                 return -EIO;
         }
         pkt->priority = 0;
+        skb_queue_head_init(&pkt_list);
 
         /* Determine initial transfer parameters */
         sdaddr = address & SBSDIO_SB_OFT_ADDR_MASK;
@@ -538,8 +653,10 @@ brcmf_sdio_ramrw(struct brcmf_sdio_dev *sdiodev, bool write, u32 address,
                 skb_put(pkt, dsize);
                 if (write)
                         memcpy(pkt->data, data, dsize);
+                skb_queue_tail(&pkt_list, pkt);
                 bcmerror = brcmf_sdio_buffrw(sdiodev, SDIO_FUNC_1, write,
-                                             sdaddr, pkt);
+                                             sdaddr, &pkt_list);
+                skb_dequeue_tail(&pkt_list);
                 if (bcmerror) {
                         brcmf_err("membytes transfer failed\n");
                         break;
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh_sdmmc.c b/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh_sdmmc.c
index 7a3c5bf33e03..289e386f01f6 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh_sdmmc.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/bcmsdh_sdmmc.c
@@ -211,78 +211,6 @@ int brcmf_sdioh_request_word(struct brcmf_sdio_dev *sdiodev,
         return err_ret;
 }
 
-/* precondition: host controller is claimed */
-static int
-brcmf_sdioh_request_data(struct brcmf_sdio_dev *sdiodev, uint write, bool fifo,
-                         uint func, uint addr, struct sk_buff *pkt, uint pktlen)
-{
-        int err_ret = 0;
-
-        if ((write) && (!fifo)) {
-                err_ret = sdio_memcpy_toio(sdiodev->func[func], addr,
-                                           ((u8 *) (pkt->data)), pktlen);
-        } else if (write) {
-                err_ret = sdio_memcpy_toio(sdiodev->func[func], addr,
-                                           ((u8 *) (pkt->data)), pktlen);
-        } else if (fifo) {
-                err_ret = sdio_readsb(sdiodev->func[func],
-                                      ((u8 *) (pkt->data)), addr, pktlen);
-        } else {
-                err_ret = sdio_memcpy_fromio(sdiodev->func[func],
-                                             ((u8 *) (pkt->data)),
-                                             addr, pktlen);
-        }
-
-        return err_ret;
-}
-
-/*
- * This function takes a queue of packets. The packets on the queue
- * are assumed to be properly aligned by the caller.
- */
-int
-brcmf_sdioh_request_chain(struct brcmf_sdio_dev *sdiodev, uint fix_inc,
-                          uint write, uint func, uint addr,
-                          struct sk_buff_head *pktq)
-{
-        bool fifo = (fix_inc == SDIOH_DATA_FIX);
-        u32 SGCount = 0;
-        int err_ret = 0;
-
-        struct sk_buff *pkt;
-
-        brcmf_dbg(SDIO, "Enter\n");
-
-        brcmf_pm_resume_wait(sdiodev, &sdiodev->request_chain_wait);
-        if (brcmf_pm_resume_error(sdiodev))
-                return -EIO;
-
-        skb_queue_walk(pktq, pkt) {
-                uint pkt_len = pkt->len;
-                pkt_len += 3;
-                pkt_len &= 0xFFFFFFFC;
-
-                err_ret = brcmf_sdioh_request_data(sdiodev, write, fifo, func,
-                                                   addr, pkt, pkt_len);
-                if (err_ret) {
-                        brcmf_err("%s FAILED %p[%d], addr=0x%05x, pkt_len=%d, ERR=0x%08x\n",
-                                  write ? "TX" : "RX", pkt, SGCount, addr,
-                                  pkt_len, err_ret);
-                } else {
-                        brcmf_dbg(SDIO, "%s xfr'd %p[%d], addr=0x%05x, len=%d\n",
-                                  write ? "TX" : "RX", pkt, SGCount, addr,
-                                  pkt_len);
-                }
-                if (!fifo)
-                        addr += pkt_len;
-
-                SGCount++;
-        }
-
-        brcmf_dbg(SDIO, "Exit\n");
-        return err_ret;
-}
-
 static int brcmf_sdioh_get_cisaddr(struct brcmf_sdio_dev *sdiodev, u32 regaddr)
 {
         /* read 24 bits and return valid 17 bit addr */
@@ -431,7 +359,6 @@ static int brcmf_ops_sdio_probe(struct sdio_func *func,
         atomic_set(&sdiodev->suspend, false);
         init_waitqueue_head(&sdiodev->request_byte_wait);
         init_waitqueue_head(&sdiodev->request_word_wait);
-        init_waitqueue_head(&sdiodev->request_chain_wait);
         init_waitqueue_head(&sdiodev->request_buffer_wait);
 
         brcmf_dbg(SDIO, "F2 found, calling brcmf_sdio_probe...\n");
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
index cb22f2f51453..264111968320 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
@@ -448,8 +448,6 @@ struct brcmf_sdio {
         uint rxblen;            /* Allocated length of rxbuf */
         u8 *rxctl;              /* Aligned pointer into rxbuf */
         u8 *rxctl_orig;         /* pointer for freeing rxctl */
-        u8 *databuf;            /* Buffer for receiving big glom packet */
-        u8 *dataptr;            /* Aligned pointer into databuf */
         uint rxlen;             /* Length of valid data in buffer */
         spinlock_t rxctl_lock;  /* protection lock for ctrl frame resources */
 
@@ -473,8 +471,6 @@ struct brcmf_sdio {
         s32 idletime;           /* Control for activity timeout */
         s32 idlecount;  /* Activity timeout counter */
         s32 idleclock;  /* How to set bus driver when idle */
-        s32 sd_rxchain;
-        bool use_rxchain;       /* If brcmf should use PKT chains */
         bool rxflow_mode;       /* Rx flow control mode */
         bool rxflow;            /* Is rx flow control on */
         bool alp_only;          /* Don't use HT clock (ALP only) */
@@ -1025,29 +1021,6 @@ static void brcmf_sdbrcm_rxfail(struct brcmf_sdio *bus, bool abort, bool rtx)
                 bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
 }
 
-/* copy a buffer into a pkt buffer chain */
-static uint brcmf_sdbrcm_glom_from_buf(struct brcmf_sdio *bus, uint len)
-{
-        uint n, ret = 0;
-        struct sk_buff *p;
-        u8 *buf;
-
-        buf = bus->dataptr;
-
-        /* copy the data */
-        skb_queue_walk(&bus->glom, p) {
-                n = min_t(uint, p->len, len);
-                memcpy(p->data, buf, n);
-                buf += n;
-                len -= n;
-                ret += n;
-                if (!len)
-                        break;
-        }
-
-        return ret;
-}
-
 /* return total length of buffer chain */
 static uint brcmf_sdbrcm_glom_len(struct brcmf_sdio *bus)
 {
@@ -1201,8 +1174,6 @@ static u8 brcmf_sdbrcm_rxglom(struct brcmf_sdio *bus, u8 rxseq)
         int errcode;
         u8 doff, sfdoff;
 
-        bool usechain = bus->use_rxchain;
-
         struct brcmf_sdio_read rd_new;
 
         /* If packets, issue read(s) and send up packet chain */
@@ -1237,7 +1208,6 @@ static u8 brcmf_sdbrcm_rxglom(struct brcmf_sdio *bus, u8 rxseq)
                         if (sublen % BRCMF_SDALIGN) {
                                 brcmf_err("sublen %d not multiple of %d\n",
                                           sublen, BRCMF_SDALIGN);
-                                usechain = false;
                         }
                         totlen += sublen;
 
@@ -1304,27 +1274,9 @@ static u8 brcmf_sdbrcm_rxglom(struct brcmf_sdio *bus, u8 rxseq)
                  * packet and and copy into the chain.
                  */
                 sdio_claim_host(bus->sdiodev->func[1]);
-                if (usechain) {
-                        errcode = brcmf_sdcard_recv_chain(bus->sdiodev,
-                                        bus->sdiodev->sbwad,
-                                        SDIO_FUNC_2, F2SYNC, &bus->glom);
-                } else if (bus->dataptr) {
-                        errcode = brcmf_sdcard_recv_buf(bus->sdiodev,
-                                        bus->sdiodev->sbwad,
-                                        SDIO_FUNC_2, F2SYNC,
-                                        bus->dataptr, dlen);
-                        sublen = (u16) brcmf_sdbrcm_glom_from_buf(bus, dlen);
-                        if (sublen != dlen) {
-                                brcmf_err("FAILED TO COPY, dlen %d sublen %d\n",
-                                          dlen, sublen);
-                                errcode = -1;
-                        }
-                        pnext = NULL;
-                } else {
-                        brcmf_err("COULDN'T ALLOC %d-BYTE GLOM, FORCE FAILURE\n",
-                                  dlen);
-                        errcode = -1;
-                }
+                errcode = brcmf_sdcard_recv_chain(bus->sdiodev,
+                                bus->sdiodev->sbwad,
+                                SDIO_FUNC_2, F2SYNC, &bus->glom);
                 sdio_release_host(bus->sdiodev->func[1]);
                 bus->sdcnt.f2rxdata++;
 
@@ -3527,9 +3479,6 @@ static void brcmf_sdbrcm_release_malloc(struct brcmf_sdio *bus)
         kfree(bus->rxbuf);
         bus->rxctl = bus->rxbuf = NULL;
         bus->rxlen = 0;
-
-        kfree(bus->databuf);
-        bus->databuf = NULL;
 }
 
 static bool brcmf_sdbrcm_probe_malloc(struct brcmf_sdio *bus)
@@ -3542,29 +3491,10 @@ static bool brcmf_sdbrcm_probe_malloc(struct brcmf_sdio *bus)
                             ALIGNMENT) + BRCMF_SDALIGN;
                 bus->rxbuf = kmalloc(bus->rxblen, GFP_ATOMIC);
                 if (!(bus->rxbuf))
-                        goto fail;
-        }
-
-        /* Allocate buffer to receive glomed packet */
-        bus->databuf = kmalloc(MAX_DATA_BUF, GFP_ATOMIC);
-        if (!(bus->databuf)) {
-                /* release rxbuf which was already located as above */
-                if (!bus->rxblen)
-                        kfree(bus->rxbuf);
-                goto fail;
+                        return false;
         }
 
-        /* Align the buffer */
-        if ((unsigned long)bus->databuf % BRCMF_SDALIGN)
-                bus->dataptr = bus->databuf + (BRCMF_SDALIGN -
-                               ((unsigned long)bus->databuf % BRCMF_SDALIGN));
-        else
-                bus->dataptr = bus->databuf;
-
         return true;
-
-fail:
-        return false;
 }
 
 static bool
@@ -3703,10 +3633,6 @@ static bool brcmf_sdbrcm_probe_init(struct brcmf_sdio *bus)
         bus->blocksize = bus->sdiodev->func[2]->cur_blksize;
         bus->roundup = min(max_roundup, bus->blocksize);
 
-        /* bus module does not support packet chaining */
-        bus->use_rxchain = false;
-        bus->sd_rxchain = false;
-
         /* SR state */
         bus->sleeping = false;
         bus->sr_enabled = false;
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/sdio_host.h b/drivers/net/wireless/brcm80211/brcmfmac/sdio_host.h
index 991c1501f7e1..793df66fe0bf 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/sdio_host.h
+++ b/drivers/net/wireless/brcm80211/brcmfmac/sdio_host.h
@@ -170,7 +170,6 @@ struct brcmf_sdio_dev {
         atomic_t suspend;               /* suspend flag */
         wait_queue_head_t request_byte_wait;
         wait_queue_head_t request_word_wait;
-        wait_queue_head_t request_chain_wait;
         wait_queue_head_t request_buffer_wait;
         struct device *dev;
         struct brcmf_bus *bus_if;
@@ -272,12 +271,6 @@ brcmf_sdioh_request_word(struct brcmf_sdio_dev *sdiodev,
                          uint rw, uint fnc, uint addr,
                          u32 *word, uint nbyte);
 
-/* read or write any buffer using cmd53 */
-extern int
-brcmf_sdioh_request_chain(struct brcmf_sdio_dev *sdiodev, uint fix_inc,
-                          uint write, uint func, uint addr,
-                          struct sk_buff_head *pktq);
-
 /* Watchdog timer interface for pm ops */
 extern void brcmf_sdio_wdtmr_enable(struct brcmf_sdio_dev *sdiodev,
                                     bool enable);