// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2016 Broadcom */ /* * Broadcom PDC Mailbox Driver * The PDC provides a ring based programming interface to one or more hardware * offload engines. For example, the PDC driver works with both SPU-M and SPU2 * cryptographic offload hardware. In some chips the PDC is referred to as MDE, * and in others the FA2/FA+ hardware is used with this PDC driver. * * The PDC driver registers with the Linux mailbox framework as a mailbox * controller, once for each PDC instance. Ring 0 for each PDC is registered as * a mailbox channel. The PDC driver uses interrupts to determine when data * transfers to and from an offload engine are complete. The PDC driver uses * threaded IRQs so that response messages are handled outside of interrupt * context. * * The PDC driver allows multiple messages to be pending in the descriptor * rings. The tx_msg_start descriptor index indicates where the last message * starts. The txin_numd value at this index indicates how many descriptor * indexes make up the message. Similar state is kept on the receive side. When * an rx interrupt indicates a response is ready, the PDC driver processes numd * descriptors from the tx and rx ring, thus processing one response at a time. */ #include <linux/errno.h> #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/debugfs.h> #include <linux/interrupt.h> #include <linux/wait.h> #include <linux/platform_device.h> #include <linux/io.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/mailbox_controller.h> #include <linux/mailbox/brcm-message.h> #include <linux/scatterlist.h> #include <linux/dma-direction.h> #include <linux/dma-mapping.h> #include <linux/dmapool.h> #define PDC_SUCCESS 0 #define RING_ENTRY_SIZE sizeof(struct dma64dd) /* # entries in PDC dma ring */ #define PDC_RING_ENTRIES 512 /* * Minimum number of ring descriptor entries that must be free to tell mailbox * framework that it can submit another request */ #define PDC_RING_SPACE_MIN 15 #define PDC_RING_SIZE (PDC_RING_ENTRIES * RING_ENTRY_SIZE) /* Rings are 8k aligned */ #define RING_ALIGN_ORDER 13 #define RING_ALIGN BIT(RING_ALIGN_ORDER) #define RX_BUF_ALIGN_ORDER 5 #define RX_BUF_ALIGN BIT(RX_BUF_ALIGN_ORDER) /* descriptor bumping macros */ #define XXD(x, max_mask) ((x) & (max_mask)) #define TXD(x, max_mask) XXD((x), (max_mask)) #define RXD(x, max_mask) XXD((x), (max_mask)) #define NEXTTXD(i, max_mask) TXD((i) + 1, (max_mask)) #define PREVTXD(i, max_mask) TXD((i) - 1, (max_mask)) #define NEXTRXD(i, max_mask) RXD((i) + 1, (max_mask)) #define PREVRXD(i, max_mask) RXD((i) - 1, (max_mask)) #define NTXDACTIVE(h, t, max_mask) TXD((t) - (h), (max_mask)) #define NRXDACTIVE(h, t, max_mask) RXD((t) - (h), (max_mask)) /* Length of BCM header at start of SPU msg, in bytes */ #define BCM_HDR_LEN 8 /* * PDC driver reserves ringset 0 on each SPU for its own use. The driver does * not currently support use of multiple ringsets on a single PDC engine. */ #define PDC_RINGSET 0 /* * Interrupt mask and status definitions. Enable interrupts for tx and rx on * ring 0 */ #define PDC_RCVINT_0 (16 + PDC_RINGSET) #define PDC_RCVINTEN_0 BIT(PDC_RCVINT_0) #define PDC_INTMASK (PDC_RCVINTEN_0) #define PDC_LAZY_FRAMECOUNT 1 #define PDC_LAZY_TIMEOUT 10000 #define PDC_LAZY_INT (PDC_LAZY_TIMEOUT | (PDC_LAZY_FRAMECOUNT << 24)) #define PDC_INTMASK_OFFSET 0x24 #define PDC_INTSTATUS_OFFSET 0x20 #define PDC_RCVLAZY0_OFFSET (0x30 + 4 * PDC_RINGSET) #define FA_RCVLAZY0_OFFSET 0x100 /* * For SPU2, configure MDE_CKSUM_CONTROL to write 17 bytes of metadata * before frame */ #define PDC_SPU2_RESP_HDR_LEN 17 #define PDC_CKSUM_CTRL BIT(27) #define PDC_CKSUM_CTRL_OFFSET 0x400 #define PDC_SPUM_RESP_HDR_LEN 32 /* * Sets the following bits for write to transmit control reg: * 11 - PtyChkDisable - parity check is disabled * 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory */ #define PDC_TX_CTL 0x000C0800 /* Bit in tx control reg to enable tx channel */ #define PDC_TX_ENABLE 0x1 /* * Sets the following bits for write to receive control reg: * 7:1 - RcvOffset - size in bytes of status region at start of rx frame buf * 9 - SepRxHdrDescEn - place start of new frames only in descriptors * that have StartOfFrame set * 10 - OflowContinue - on rx FIFO overflow, clear rx fifo, discard all * remaining bytes in current frame, report error * in rx frame status for current frame * 11 - PtyChkDisable - parity check is disabled * 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory */ #define PDC_RX_CTL 0x000C0E00 /* Bit in rx control reg to enable rx channel */ #define PDC_RX_ENABLE 0x1 #define CRYPTO_D64_RS0_CD_MASK ((PDC_RING_ENTRIES * RING_ENTRY_SIZE) - 1) /* descriptor flags */ #define D64_CTRL1_EOT BIT(28) /* end of descriptor table */ #define D64_CTRL1_IOC BIT(29) /* interrupt on complete */ #define D64_CTRL1_EOF BIT(30) /* end of frame */ #define D64_CTRL1_SOF BIT(31) /* start of frame */ #define RX_STATUS_OVERFLOW 0x00800000 #define RX_STATUS_LEN 0x0000FFFF #define PDC_TXREGS_OFFSET 0x200 #define PDC_RXREGS_OFFSET 0x220 /* Maximum size buffer the DMA engine can handle */ #define PDC_DMA_BUF_MAX 16384 enum pdc_hw { FA_HW, /* FA2/FA+ hardware (i.e. Northstar Plus) */ PDC_HW /* PDC/MDE hardware (i.e. Northstar 2, Pegasus) */ }; struct pdc_dma_map { void *ctx; /* opaque context associated with frame */ }; /* dma descriptor */ struct dma64dd { u32 ctrl1; /* misc control bits */ u32 ctrl2; /* buffer count and address extension */ u32 addrlow; /* memory address of the date buffer, bits 31:0 */ u32 addrhigh; /* memory address of the date buffer, bits 63:32 */ }; /* dma registers per channel(xmt or rcv) */ struct dma64_regs { u32 control; /* enable, et al */ u32 ptr; /* last descriptor posted to chip */ u32 addrlow; /* descriptor ring base address low 32-bits */ u32 addrhigh; /* descriptor ring base address bits 63:32 */ u32 status0; /* last rx descriptor written by hw */ u32 status1; /* driver does not use */ }; /* cpp contortions to concatenate w/arg prescan */ #ifndef PAD #define _PADLINE(line) pad ## line #define _XSTR(line) _PADLINE(line) #define PAD _XSTR(__LINE__) #endif /* PAD */ /* dma registers. matches hw layout. */ struct dma64 { struct dma64_regs dmaxmt; /* dma tx */ u32 PAD[2]; struct dma64_regs dmarcv; /* dma rx */ u32 PAD[2]; }; /* PDC registers */ struct pdc_regs { u32 devcontrol; /* 0x000 */ u32 devstatus; /* 0x004 */ u32 PAD; u32 biststatus; /* 0x00c */ u32 PAD[4]; u32 intstatus; /* 0x020 */ u32 intmask; /* 0x024 */ u32 gptimer; /* 0x028 */ u32 PAD; u32 intrcvlazy_0; /* 0x030 (Only in PDC, not FA2) */ u32 intrcvlazy_1; /* 0x034 (Only in PDC, not FA2) */ u32 intrcvlazy_2; /* 0x038 (Only in PDC, not FA2) */ u32 intrcvlazy_3; /* 0x03c (Only in PDC, not FA2) */ u32 PAD[48]; u32 fa_intrecvlazy; /* 0x100 (Only in FA2, not PDC) */ u32 flowctlthresh; /* 0x104 */ u32 wrrthresh; /* 0x108 */ u32 gmac_idle_cnt_thresh; /* 0x10c */ u32 PAD[4]; u32 ifioaccessaddr; /* 0x120 */ u32 ifioaccessbyte; /* 0x124 */ u32 ifioaccessdata; /* 0x128 */ u32 PAD[21]; u32 phyaccess; /* 0x180 */ u32 PAD; u32 phycontrol; /* 0x188 */ u32 txqctl; /* 0x18c */ u32 rxqctl; /* 0x190 */ u32 gpioselect; /* 0x194 */ u32 gpio_output_en; /* 0x198 */ u32 PAD; /* 0x19c */ u32 txq_rxq_mem_ctl; /* 0x1a0 */ u32 memory_ecc_status; /* 0x1a4 */ u32 serdes_ctl; /* 0x1a8 */ u32 serdes_status0; /* 0x1ac */ u32 serdes_status1; /* 0x1b0 */ u32 PAD[11]; /* 0x1b4-1dc */ u32 clk_ctl_st; /* 0x1e0 */ u32 hw_war; /* 0x1e4 (Only in PDC, not FA2) */ u32 pwrctl; /* 0x1e8 */ u32 PAD[5]; #define PDC_NUM_DMA_RINGS 4 struct dma64 dmaregs[PDC_NUM_DMA_RINGS]; /* 0x0200 - 0x2fc */ /* more registers follow, but we don't use them */ }; /* structure for allocating/freeing DMA rings */ struct pdc_ring_alloc { dma_addr_t dmabase; /* DMA address of start of ring */ void *vbase; /* base kernel virtual address of ring */ u32 size; /* ring allocation size in bytes */ }; /* * context associated with a receive descriptor. * @rxp_ctx: opaque context associated with frame that starts at each * rx ring index. * @dst_sg: Scatterlist used to form reply frames beginning at a given ring * index. Retained in order to unmap each sg after reply is processed. * @rxin_numd: Number of rx descriptors associated with the message that starts * at a descriptor index. Not set for every index. For example, * if descriptor index i points to a scatterlist with 4 entries, * then the next three descriptor indexes don't have a value set. * @resp_hdr: Virtual address of buffer used to catch DMA rx status * @resp_hdr_daddr: physical address of DMA rx status buffer */ struct pdc_rx_ctx { void *rxp_ctx; struct scatterlist *dst_sg; u32 rxin_numd; void *resp_hdr; dma_addr_t resp_hdr_daddr; }; /* PDC state structure */ struct pdc_state { /* Index of the PDC whose state is in this structure instance */ u8 pdc_idx; /* Platform device for this PDC instance */ struct platform_device *pdev; /* * Each PDC instance has a mailbox controller. PDC receives request * messages through mailboxes, and sends response messages through the * mailbox framework. */ struct mbox_controller mbc; unsigned int pdc_irq; /* tasklet for deferred processing after DMA rx interrupt */ struct tasklet_struct rx_tasklet; /* Number of bytes of receive status prior to each rx frame */ u32 rx_status_len; /* Whether a BCM header is prepended to each frame */ bool use_bcm_hdr; /* Sum of length of BCM header and rx status header */ u32 pdc_resp_hdr_len; /* The base virtual address of DMA hw registers */ void __iomem *pdc_reg_vbase; /* Pool for allocation of DMA rings */ struct dma_pool *ring_pool; /* Pool for allocation of metadata buffers for response messages */ struct dma_pool *rx_buf_pool; /* * The base virtual address of DMA tx/rx descriptor rings. Corresponding * DMA address and size of ring allocation. */ struct pdc_ring_alloc tx_ring_alloc; struct pdc_ring_alloc rx_ring_alloc; struct pdc_regs *regs; /* start of PDC registers */ struct dma64_regs *txregs_64; /* dma tx engine registers */ struct dma64_regs *rxregs_64; /* dma rx engine registers */ /* * Arrays of PDC_RING_ENTRIES descriptors * To use multiple ringsets, this needs to be extended */ struct dma64dd *txd_64; /* tx descriptor ring */ struct dma64dd *rxd_64; /* rx descriptor ring */ /* descriptor ring sizes */ u32 ntxd; /* # tx descriptors */ u32 nrxd; /* # rx descriptors */ u32 nrxpost; /* # rx buffers to keep posted */ u32 ntxpost; /* max number of tx buffers that can be posted */ /* * Index of next tx descriptor to reclaim. That is, the descriptor * index of the oldest tx buffer for which the host has yet to process * the corresponding response. */ u32 txin; /* * Index of the first receive descriptor for the sequence of * message fragments currently under construction. Used to build up * the rxin_numd count for a message. Updated to rxout when the host * starts a new sequence of rx buffers for a new message. */ u32 tx_msg_start; /* Index of next tx descriptor to post. */ u32 txout; /* * Number of tx descriptors associated with the message that starts * at this tx descriptor index. */ u32 txin_numd[PDC_RING_ENTRIES]; /* * Index of next rx descriptor to reclaim. This is the index of * the next descriptor whose data has yet to be processed by the host. */ u32 rxin; /* * Index of the first receive descriptor for the sequence of * message fragments currently under construction. Used to build up * the rxin_numd count for a message. Updated to rxout when the host * starts a new sequence of rx buffers for a new message. */ u32 rx_msg_start; /* * Saved value of current hardware rx descriptor index. * The last rx buffer written by the hw is the index previous to * this one. */ u32 last_rx_curr; /* Index of next rx descriptor to post. */ u32 rxout; struct pdc_rx_ctx rx_ctx[PDC_RING_ENTRIES]; /* * Scatterlists used to form request and reply frames beginning at a * given ring index. Retained in order to unmap each sg after reply * is processed */ struct scatterlist *src_sg[PDC_RING_ENTRIES]; /* counters */ u32 pdc_requests; /* number of request messages submitted */ u32 pdc_replies; /* number of reply messages received */ u32 last_tx_not_done; /* too few tx descriptors to indicate done */ u32 tx_ring_full; /* unable to accept msg because tx ring full */ u32 rx_ring_full; /* unable to accept msg because rx ring full */ u32 txnobuf; /* unable to create tx descriptor */ u32 rxnobuf; /* unable to create rx descriptor */ u32 rx_oflow; /* count of rx overflows */ /* hardware type - FA2 or PDC/MDE */ enum pdc_hw hw_type; }; /* Global variables */ struct pdc_globals { /* Actual number of SPUs in hardware, as reported by device tree */ u32 num_spu; }; static struct pdc_globals pdcg; /* top level debug FS directory for PDC driver */ static struct dentry *debugfs_dir; static ssize_t pdc_debugfs_read(struct file *filp, char __user *ubuf, size_t count, loff_t *offp) { struct pdc_state *pdcs; char *buf; ssize_t ret, out_offset, out_count; out_count = 512; buf = kmalloc(out_count, GFP_KERNEL); if (!buf) return -ENOMEM; pdcs = filp->private_data; out_offset = 0; out_offset += scnprintf(buf + out_offset, out_count - out_offset, "SPU %u stats:\n", pdcs->pdc_idx); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "PDC requests....................%u\n", pdcs->pdc_requests); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "PDC responses...................%u\n", pdcs->pdc_replies); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Tx not done.....................%u\n", pdcs->last_tx_not_done); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Tx ring full....................%u\n", pdcs->tx_ring_full); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Rx ring full....................%u\n", pdcs->rx_ring_full); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Tx desc write fail. Ring full...%u\n", pdcs->txnobuf); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Rx desc write fail. Ring full...%u\n", pdcs->rxnobuf); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Receive overflow................%u\n", pdcs->rx_oflow); out_offset += scnprintf(buf + out_offset, out_count - out_offset, "Num frags in rx ring............%u\n", NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, pdcs->nrxpost)); if (out_offset > out_count) out_offset = out_count; ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); kfree(buf); return ret; } static const struct file_operations pdc_debugfs_stats = { .owner = THIS_MODULE, .open = simple_open, .read = pdc_debugfs_read, }; /** * pdc_setup_debugfs() - Create the debug FS directories. If the top-level * directory has not yet been created, create it now. Create a stats file in * this directory for a SPU. * @pdcs: PDC state structure */ static void pdc_setup_debugfs(struct pdc_state *pdcs) { char spu_stats_name[16]; if (!debugfs_initialized()) return; snprintf(spu_stats_name, 16, "pdc%d_stats", pdcs->pdc_idx); if (!debugfs_dir) debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); /* S_IRUSR == 0400 */ debugfs_create_file(spu_stats_name, 0400, debugfs_dir, pdcs, &pdc_debugfs_stats); } static void pdc_free_debugfs(void) { debugfs_remove_recursive(debugfs_dir); debugfs_dir = NULL; } /** * pdc_build_rxd() - Build DMA descriptor to receive SPU result. * @pdcs: PDC state for SPU that will generate result * @dma_addr: DMA address of buffer that descriptor is being built for * @buf_len: Length of the receive buffer, in bytes * @flags: Flags to be stored in descriptor */ static inline void pdc_build_rxd(struct pdc_state *pdcs, dma_addr_t dma_addr, u32 buf_len, u32 flags) { struct device *dev = &pdcs->pdev->dev; struct dma64dd *rxd = &pdcs->rxd_64[pdcs->rxout]; dev_dbg(dev, "Writing rx descriptor for PDC %u at index %u with length %u. flags %#x\n", pdcs->pdc_idx, pdcs->rxout, buf_len, flags); rxd->addrlow = cpu_to_le32(lower_32_bits(dma_addr)); rxd->addrhigh = cpu_to_le32(upper_32_bits(dma_addr)); rxd->ctrl1 = cpu_to_le32(flags); rxd->ctrl2 = cpu_to_le32(buf_len); /* bump ring index and return */ pdcs->rxout = NEXTRXD(pdcs->rxout, pdcs->nrxpost); } /** * pdc_build_txd() - Build a DMA descriptor to transmit a SPU request to * hardware. * @pdcs: PDC state for the SPU that will process this request * @dma_addr: DMA address of packet to be transmitted * @buf_len: Length of tx buffer, in bytes * @flags: Flags to be stored in descriptor */ static inline void pdc_build_txd(struct pdc_state *pdcs, dma_addr_t dma_addr, u32 buf_len, u32 flags) { struct device *dev = &pdcs->pdev->dev; struct dma64dd *txd = &pdcs->txd_64[pdcs->txout]; dev_dbg(dev, "Writing tx descriptor for PDC %u at index %u with length %u, flags %#x\n", pdcs->pdc_idx, pdcs->txout, buf_len, flags); txd->addrlow = cpu_to_le32(lower_32_bits(dma_addr)); txd->addrhigh = cpu_to_le32(upper_32_bits(dma_addr)); txd->ctrl1 = cpu_to_le32(flags); txd->ctrl2 = cpu_to_le32(buf_len); /* bump ring index and return */ pdcs->txout = NEXTTXD(pdcs->txout, pdcs->ntxpost); } /** * pdc_receive_one() - Receive a response message from a given SPU. * @pdcs: PDC state for the SPU to receive from * * When the return code indicates success, the response message is available in * the receive buffers provided prior to submission of the request. * * Return: PDC_SUCCESS if one or more receive descriptors was processed * -EAGAIN indicates that no response message is available * -EIO an error occurred */ static int pdc_receive_one(struct pdc_state *pdcs) { struct device *dev = &pdcs->pdev->dev; struct mbox_controller *mbc; struct mbox_chan *chan; struct brcm_message mssg; u32 len, rx_status; u32 num_frags; u8 *resp_hdr; /* virtual addr of start of resp message DMA header */ u32 frags_rdy; /* number of fragments ready to read */ u32 rx_idx; /* ring index of start of receive frame */ dma_addr_t resp_hdr_daddr; struct pdc_rx_ctx *rx_ctx; mbc = &pdcs->mbc; chan = &mbc->chans[0]; mssg.type = BRCM_MESSAGE_SPU; /* * return if a complete response message is not yet ready. * rxin_numd[rxin] is the number of fragments in the next msg * to read. */ frags_rdy = NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, pdcs->nrxpost); if ((frags_rdy == 0) || (frags_rdy < pdcs->rx_ctx[pdcs->rxin].rxin_numd)) /* No response ready */ return -EAGAIN; num_frags = pdcs->txin_numd[pdcs->txin]; WARN_ON(num_frags == 0); dma_unmap_sg(dev, pdcs->src_sg[pdcs->txin], sg_nents(pdcs->src_sg[pdcs->txin]), DMA_TO_DEVICE); pdcs->txin = (pdcs->txin + num_frags) & pdcs->ntxpost; dev_dbg(dev, "PDC %u reclaimed %d tx descriptors", pdcs->pdc_idx, num_frags); rx_idx = pdcs->rxin; rx_ctx = &pdcs->rx_ctx[rx_idx]; num_frags = rx_ctx->rxin_numd; /* Return opaque context with result */ mssg.ctx = rx_ctx->rxp_ctx; rx_ctx->rxp_ctx = NULL; resp_hdr = rx_ctx->resp_hdr; resp_hdr_daddr = rx_ctx->resp_hdr_daddr; dma_unmap_sg(dev, rx_ctx->dst_sg, sg_nents(rx_ctx->dst_sg), DMA_FROM_DEVICE); pdcs->rxin = (pdcs->rxin + num_frags) & pdcs->nrxpost; dev_dbg(dev, "PDC %u reclaimed %d rx descriptors", pdcs->pdc_idx, num_frags); dev_dbg(dev, "PDC %u txin %u, txout %u, rxin %u, rxout %u, last_rx_curr %u\n", pdcs->pdc_idx, pdcs->txin, pdcs->txout, pdcs->rxin, pdcs->rxout, pdcs->last_rx_curr); if (pdcs->pdc_resp_hdr_len == PDC_SPUM_RESP_HDR_LEN) { /* * For SPU-M, get length of response msg and rx overflow status. */ rx_status = *((u32 *)resp_hdr); len = rx_status & RX_STATUS_LEN; dev_dbg(dev, "SPU response length %u bytes", len); if (unlikely(((rx_status & RX_STATUS_OVERFLOW) || (!len)))) { if (rx_status & RX_STATUS_OVERFLOW) { dev_err_ratelimited(dev, "crypto receive overflow"); pdcs->rx_oflow++; } else { dev_info_ratelimited(dev, "crypto rx len = 0"); } return -EIO; } } dma_pool_free(pdcs->rx_buf_pool, resp_hdr, resp_hdr_daddr); mbox_chan_received_data(chan, &mssg); pdcs->pdc_replies++; return PDC_SUCCESS; } /** * pdc_receive() - Process as many responses as are available in the rx ring. * @pdcs: PDC state * * Called within the hard IRQ. * Return: */ static int pdc_receive(struct pdc_state *pdcs) { int rx_status; /* read last_rx_curr from register once */ pdcs->last_rx_curr = (ioread32((const void __iomem *)&pdcs->rxregs_64->status0) & CRYPTO_D64_RS0_CD_MASK) / RING_ENTRY_SIZE; do { /* Could be many frames ready */ rx_status = pdc_receive_one(pdcs); } while (rx_status == PDC_SUCCESS); return 0; } /** * pdc_tx_list_sg_add() - Add the buffers in a scatterlist to the transmit * descriptors for a given SPU. The scatterlist buffers contain the data for a * SPU request message. * @spu_idx: The index of the SPU to submit the request to, [0, max_spu) * @sg: Scatterlist whose buffers contain part of the SPU request * * If a scatterlist buffer is larger than PDC_DMA_BUF_MAX, multiple descriptors * are written for that buffer, each <= PDC_DMA_BUF_MAX byte in length. * * Return: PDC_SUCCESS if successful * < 0 otherwise */ static int pdc_tx_list_sg_add(struct pdc_state *pdcs, struct scatterlist *sg) { u32 flags = 0; u32 eot; u32 tx_avail; /* * Num descriptors needed. Conservatively assume we need a descriptor * for every entry in sg. */ u32 num_desc; u32 desc_w = 0; /* Number of tx descriptors written */ u32 bufcnt; /* Number of bytes of buffer pointed to by descriptor */ dma_addr_t databufptr; /* DMA address to put in descriptor */ num_desc = (u32)sg_nents(sg); /* check whether enough tx descriptors are available */ tx_avail = pdcs->ntxpost - NTXDACTIVE(pdcs->txin, pdcs->txout, pdcs->ntxpost); if (unlikely(num_desc > tx_avail)) { pdcs->txnobuf++; return -ENOSPC; } /* build tx descriptors */ if (pdcs->tx_msg_start == pdcs->txout) { /* Start of frame */ pdcs->txin_numd[pdcs->tx_msg_start] = 0; pdcs->src_sg[pdcs->txout] = sg; flags = D64_CTRL1_SOF; } while (sg) { if (unlikely(pdcs->txout == (pdcs->ntxd - 1))) eot = D64_CTRL1_EOT; else eot = 0; /* * If sg buffer larger than PDC limit, split across * multiple descriptors */ bufcnt = sg_dma_len(sg); databufptr = sg_dma_address(sg); while (bufcnt > PDC_DMA_BUF_MAX) { pdc_build_txd(pdcs, databufptr, PDC_DMA_BUF_MAX, flags | eot); desc_w++; bufcnt -= PDC_DMA_BUF_MAX; databufptr += PDC_DMA_BUF_MAX; if (unlikely(pdcs->txout == (pdcs->ntxd - 1))) eot = D64_CTRL1_EOT; else eot = 0; } sg = sg_next(sg); if (!sg) /* Writing last descriptor for frame */ flags |= (D64_CTRL1_EOF | D64_CTRL1_IOC); pdc_build_txd(pdcs, databufptr, bufcnt, flags | eot); desc_w++; /* Clear start of frame after first descriptor */ flags &= ~D64_CTRL1_SOF; } pdcs->txin_numd[pdcs->tx_msg_start] += desc_w; return PDC_SUCCESS; } /** * pdc_tx_list_final() - Initiate DMA transfer of last frame written to tx * ring. * @pdcs: PDC state for SPU to process the request * * Sets the index of the last descriptor written in both the rx and tx ring. * * Return: PDC_SUCCESS */ static int pdc_tx_list_final(struct pdc_state *pdcs) { /* * write barrier to ensure all register writes are complete * before chip starts to process new request */ wmb(); iowrite32(pdcs->rxout << 4, &pdcs->rxregs_64->ptr); iowrite32(pdcs->txout << 4, &pdcs->txregs_64->ptr); pdcs->pdc_requests++; return PDC_SUCCESS; } /** * pdc_rx_list_init() - Start a new receive descriptor list for a given PDC. * @pdcs: PDC state for SPU handling request * @dst_sg: scatterlist providing rx buffers for response to be returned to * mailbox client * @ctx: Opaque context for this request * * Posts a single receive descriptor to hold the metadata that precedes a * response. For example, with SPU-M, the metadata is a 32-byte DMA header and * an 8-byte BCM header. Moves the msg_start descriptor indexes for both tx and * rx to indicate the start of a new message. * * Return: PDC_SUCCESS if successful * < 0 if an error (e.g., rx ring is full) */ static int pdc_rx_list_init(struct pdc_state *pdcs, struct scatterlist *dst_sg, void *ctx) { u32 flags = 0; u32 rx_avail; u32 rx_pkt_cnt = 1; /* Adding a single rx buffer */ dma_addr_t daddr; void *vaddr; struct pdc_rx_ctx *rx_ctx; rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout, pdcs->nrxpost); if (unlikely(rx_pkt_cnt > rx_avail)) { pdcs->rxnobuf++; return -ENOSPC; } /* allocate a buffer for the dma rx status */ vaddr = dma_pool_zalloc(pdcs->rx_buf_pool, GFP_ATOMIC, &daddr); if (unlikely(!vaddr)) return -ENOMEM; /* * Update msg_start indexes for both tx and rx to indicate the start * of a new sequence of descriptor indexes that contain the fragments * of the same message. */ pdcs->rx_msg_start = pdcs->rxout; pdcs->tx_msg_start = pdcs->txout; /* This is always the first descriptor in the receive sequence */ flags = D64_CTRL1_SOF; pdcs->rx_ctx[pdcs->rx_msg_start].rxin_numd = 1; if (unlikely(pdcs->rxout == (pdcs->nrxd - 1))) flags |= D64_CTRL1_EOT; rx_ctx = &pdcs->rx_ctx[pdcs->rxout]; rx_ctx->rxp_ctx = ctx; rx_ctx->dst_sg = dst_sg; rx_ctx->resp_hdr = vaddr; rx_ctx->resp_hdr_daddr = daddr; pdc_build_rxd(pdcs, daddr, pdcs->pdc_resp_hdr_len, flags); return PDC_SUCCESS; } /** * pdc_rx_list_sg_add() - Add the buffers in a scatterlist to the receive * descriptors for a given SPU. The caller must have already DMA mapped the * scatterlist. * @spu_idx: Indicates which SPU the buffers are for * @sg: Scatterlist whose buffers are added to the receive ring * * If a receive buffer in the scatterlist is larger than PDC_DMA_BUF_MAX, * multiple receive descriptors are written, each with a buffer <= * PDC_DMA_BUF_MAX. * * Return: PDC_SUCCESS if successful * < 0 otherwise (e.g., receive ring is full) */ static int pdc_rx_list_sg_add(struct pdc_state *pdcs, struct scatterlist *sg) { u32 flags = 0; u32 rx_avail; /* * Num descriptors needed. Conservatively assume we need a descriptor * for every entry from our starting point in the scatterlist. */ u32 num_desc; u32 desc_w = 0; /* Number of tx descriptors written */ u32 bufcnt; /* Number of bytes of buffer pointed to by descriptor */ dma_addr_t databufptr; /* DMA address to put in descriptor */ num_desc = (u32)sg_nents(sg); rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout, pdcs->nrxpost); if (unlikely(num_desc > rx_avail)) { pdcs->rxnobuf++; return -ENOSPC; } while (sg) { if (unlikely(pdcs->rxout == (pdcs->nrxd - 1))) flags = D64_CTRL1_EOT; else flags = 0; /* * If sg buffer larger than PDC limit, split across * multiple descriptors */ bufcnt = sg_dma_len(sg); databufptr = sg_dma_address(sg); while (bufcnt > PDC_DMA_BUF_MAX) { pdc_build_rxd(pdcs, databufptr, PDC_DMA_BUF_MAX, flags); desc_w++; bufcnt -= PDC_DMA_BUF_MAX; databufptr += PDC_DMA_BUF_MAX; if (unlikely(pdcs->rxout == (pdcs->nrxd - 1))) flags = D64_CTRL1_EOT; else flags = 0; } pdc_build_rxd(pdcs, databufptr, bufcnt, flags); desc_w++; sg = sg_next(sg); } pdcs->rx_ctx[pdcs->rx_msg_start].rxin_numd += desc_w; return PDC_SUCCESS; } /** * pdc_irq_handler() - Interrupt handler called in interrupt context. * @irq: Interrupt number that has fired * @data: device struct for DMA engine that generated the interrupt * * We have to clear the device interrupt status flags here. So cache the * status for later use in the thread function. Other than that, just return * WAKE_THREAD to invoke the thread function. * * Return: IRQ_WAKE_THREAD if interrupt is ours * IRQ_NONE otherwise */ static irqreturn_t pdc_irq_handler(int irq, void *data) { struct device *dev = (struct device *)data; struct pdc_state *pdcs = dev_get_drvdata(dev); u32 intstatus = ioread32(pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET); if (unlikely(intstatus == 0)) return IRQ_NONE; /* Disable interrupts until soft handler runs */ iowrite32(0, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET); /* Clear interrupt flags in device */ iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET); /* Wakeup IRQ thread */ tasklet_schedule(&pdcs->rx_tasklet); return IRQ_HANDLED; } /** * pdc_tasklet_cb() - Tasklet callback that runs the deferred processing after * a DMA receive interrupt. Reenables the receive interrupt. * @data: PDC state structure */ static void pdc_tasklet_cb(struct tasklet_struct *t) { struct pdc_state *pdcs = from_tasklet(pdcs, t, rx_tasklet); pdc_receive(pdcs); /* reenable interrupts */ iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET); } /** * pdc_ring_init() - Allocate DMA rings and initialize constant fields of * descriptors in one ringset. * @pdcs: PDC instance state * @ringset: index of ringset being used * * Return: PDC_SUCCESS if ring initialized * < 0 otherwise */ static int pdc_ring_init(struct pdc_state *pdcs, int ringset) { int i; int err = PDC_SUCCESS; struct dma64 *dma_reg; struct device *dev = &pdcs->pdev->dev; struct pdc_ring_alloc tx; struct pdc_ring_alloc rx; /* Allocate tx ring */ tx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &tx.dmabase); if (unlikely(!tx.vbase)) { err = -ENOMEM; goto done; } /* Allocate rx ring */ rx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &rx.dmabase); if (unlikely(!rx.vbase)) { err = -ENOMEM; goto fail_dealloc; } dev_dbg(dev, " - base DMA addr of tx ring %pad", &tx.dmabase); dev_dbg(dev, " - base virtual addr of tx ring %p", tx.vbase); dev_dbg(dev, " - base DMA addr of rx ring %pad", &rx.dmabase); dev_dbg(dev, " - base virtual addr of rx ring %p", rx.vbase); memcpy(&pdcs->tx_ring_alloc, &tx, sizeof(tx)); memcpy(&pdcs->rx_ring_alloc, &rx, sizeof(rx)); pdcs->rxin = 0; pdcs->rx_msg_start = 0; pdcs->last_rx_curr = 0; pdcs->rxout = 0; pdcs->txin = 0; pdcs->tx_msg_start = 0; pdcs->txout = 0; /* Set descriptor array base addresses */ pdcs->txd_64 = (struct dma64dd *)pdcs->tx_ring_alloc.vbase; pdcs->rxd_64 = (struct dma64dd *)pdcs->rx_ring_alloc.vbase; /* Tell device the base DMA address of each ring */ dma_reg = &pdcs->regs->dmaregs[ringset]; /* But first disable DMA and set curptr to 0 for both TX & RX */ iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control); iowrite32((PDC_RX_CTL + (pdcs->rx_status_len << 1)), &dma_reg->dmarcv.control); iowrite32(0, &dma_reg->dmaxmt.ptr); iowrite32(0, &dma_reg->dmarcv.ptr); /* Set base DMA addresses */ iowrite32(lower_32_bits(pdcs->tx_ring_alloc.dmabase), &dma_reg->dmaxmt.addrlow); iowrite32(upper_32_bits(pdcs->tx_ring_alloc.dmabase), &dma_reg->dmaxmt.addrhigh); iowrite32(lower_32_bits(pdcs->rx_ring_alloc.dmabase), &dma_reg->dmarcv.addrlow); iowrite32(upper_32_bits(pdcs->rx_ring_alloc.dmabase), &dma_reg->dmarcv.addrhigh); /* Re-enable DMA */ iowrite32(PDC_TX_CTL | PDC_TX_ENABLE, &dma_reg->dmaxmt.control); iowrite32((PDC_RX_CTL | PDC_RX_ENABLE | (pdcs->rx_status_len << 1)), &dma_reg->dmarcv.control); /* Initialize descriptors */ for (i = 0; i < PDC_RING_ENTRIES; i++) { /* Every tx descriptor can be used for start of frame. */ if (i != pdcs->ntxpost) { iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOF, &pdcs->txd_64[i].ctrl1); } else { /* Last descriptor in ringset. Set End of Table. */ iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOF | D64_CTRL1_EOT, &pdcs->txd_64[i].ctrl1); } /* Every rx descriptor can be used for start of frame */ if (i != pdcs->nrxpost) { iowrite32(D64_CTRL1_SOF, &pdcs->rxd_64[i].ctrl1); } else { /* Last descriptor in ringset. Set End of Table. */ iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOT, &pdcs->rxd_64[i].ctrl1); } } return PDC_SUCCESS; fail_dealloc: dma_pool_free(pdcs->ring_pool, tx.vbase, tx.dmabase); done: return err; } static void pdc_ring_free(struct pdc_state *pdcs) { if (pdcs->tx_ring_alloc.vbase) { dma_pool_free(pdcs->ring_pool, pdcs->tx_ring_alloc.vbase, pdcs->tx_ring_alloc.dmabase); pdcs->tx_ring_alloc.vbase = NULL; } if (pdcs->rx_ring_alloc.vbase) { dma_pool_free(pdcs->ring_pool, pdcs->rx_ring_alloc.vbase, pdcs->rx_ring_alloc.dmabase); pdcs->rx_ring_alloc.vbase = NULL; } } /** * pdc_desc_count() - Count the number of DMA descriptors that will be required * for a given scatterlist. Account for the max length of a DMA buffer. * @sg: Scatterlist to be DMA'd * Return: Number of descriptors required */ static u32 pdc_desc_count(struct scatterlist *sg) { u32 cnt = 0; while (sg) { cnt += ((sg->length / PDC_DMA_BUF_MAX) + 1); sg = sg_next(sg); } return cnt; } /** * pdc_rings_full() - Check whether the tx ring has room for tx_cnt descriptors * and the rx ring has room for rx_cnt descriptors. * @pdcs: PDC state * @tx_cnt: The number of descriptors required in the tx ring * @rx_cnt: The number of descriptors required i the rx ring * * Return: true if one of the rings does not have enough space * false if sufficient space is available in both rings */ static bool pdc_rings_full(struct pdc_state *pdcs, int tx_cnt, int rx_cnt) { u32 rx_avail; u32 tx_avail; bool full = false; /* Check if the tx and rx rings are likely to have enough space */ rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout, pdcs->nrxpost); if (unlikely(rx_cnt > rx_avail)) { pdcs->rx_ring_full++; full = true; } if (likely(!full)) { tx_avail = pdcs->ntxpost - NTXDACTIVE(pdcs->txin, pdcs->txout, pdcs->ntxpost); if (unlikely(tx_cnt > tx_avail)) { pdcs->tx_ring_full++; full = true; } } return full; } /** * pdc_last_tx_done() - If both the tx and rx rings have at least * PDC_RING_SPACE_MIN descriptors available, then indicate that the mailbox * framework can submit another message. * @chan: mailbox channel to check * Return: true if PDC can accept another message on this channel */ static bool pdc_last_tx_done(struct mbox_chan *chan) { struct pdc_state *pdcs = chan->con_priv; bool ret; if (unlikely(pdc_rings_full(pdcs, PDC_RING_SPACE_MIN, PDC_RING_SPACE_MIN))) { pdcs->last_tx_not_done++; ret = false; } else { ret = true; } return ret; } /** * pdc_send_data() - mailbox send_data function * @chan: The mailbox channel on which the data is sent. The channel * corresponds to a DMA ringset. * @data: The mailbox message to be sent. The message must be a * brcm_message structure. * * This function is registered as the send_data function for the mailbox * controller. From the destination scatterlist in the mailbox message, it * creates a sequence of receive descriptors in the rx ring. From the source * scatterlist, it creates a sequence of transmit descriptors in the tx ring. * After creating the descriptors, it writes the rx ptr and tx ptr registers to * initiate the DMA transfer. * * This function does the DMA map and unmap of the src and dst scatterlists in * the mailbox message. * * Return: 0 if successful * -ENOTSUPP if the mailbox message is a type this driver does not * support * < 0 if an error */ static int pdc_send_data(struct mbox_chan *chan, void *data) { struct pdc_state *pdcs = chan->con_priv; struct device *dev = &pdcs->pdev->dev; struct brcm_message *mssg = data; int err = PDC_SUCCESS; int src_nent; int dst_nent; int nent; u32 tx_desc_req; u32 rx_desc_req; if (unlikely(mssg->type != BRCM_MESSAGE_SPU)) return -ENOTSUPP; src_nent = sg_nents(mssg->spu.src); if (likely(src_nent)) { nent = dma_map_sg(dev, mssg->spu.src, src_nent, DMA_TO_DEVICE); if (unlikely(nent == 0)) return -EIO; } dst_nent = sg_nents(mssg->spu.dst); if (likely(dst_nent)) { nent = dma_map_sg(dev, mssg->spu.dst, dst_nent, DMA_FROM_DEVICE); if (unlikely(nent == 0)) { dma_unmap_sg(dev, mssg->spu.src, src_nent, DMA_TO_DEVICE); return -EIO; } } /* * Check if the tx and rx rings have enough space. Do this prior to * writing any tx or rx descriptors. Need to ensure that we do not write * a partial set of descriptors, or write just rx descriptors but * corresponding tx descriptors don't fit. Note that we want this check * and the entire sequence of descriptor to happen without another * thread getting in. The channel spin lock in the mailbox framework * ensures this. */ tx_desc_req = pdc_desc_count(mssg->spu.src); rx_desc_req = pdc_desc_count(mssg->spu.dst); if (unlikely(pdc_rings_full(pdcs, tx_desc_req, rx_desc_req + 1))) return -ENOSPC; /* Create rx descriptors to SPU catch response */ err = pdc_rx_list_init(pdcs, mssg->spu.dst, mssg->ctx); err |= pdc_rx_list_sg_add(pdcs, mssg->spu.dst); /* Create tx descriptors to submit SPU request */ err |= pdc_tx_list_sg_add(pdcs, mssg->spu.src); err |= pdc_tx_list_final(pdcs); /* initiate transfer */ if (unlikely(err)) dev_err(&pdcs->pdev->dev, "%s failed with error %d", __func__, err); return err; } static int pdc_startup(struct mbox_chan *chan) { return pdc_ring_init(chan->con_priv, PDC_RINGSET); } static void pdc_shutdown(struct mbox_chan *chan) { struct pdc_state *pdcs = chan->con_priv; if (!pdcs) return; dev_dbg(&pdcs->pdev->dev, "Shutdown mailbox channel for PDC %u", pdcs->pdc_idx); pdc_ring_free(pdcs); } /** * pdc_hw_init() - Use the given initialization parameters to initialize the * state for one of the PDCs. * @pdcs: state of the PDC */ static void pdc_hw_init(struct pdc_state *pdcs) { struct platform_device *pdev; struct device *dev; struct dma64 *dma_reg; int ringset = PDC_RINGSET; pdev = pdcs->pdev; dev = &pdev->dev; dev_dbg(dev, "PDC %u initial values:", pdcs->pdc_idx); dev_dbg(dev, "state structure: %p", pdcs); dev_dbg(dev, " - base virtual addr of hw regs %p", pdcs->pdc_reg_vbase); /* initialize data structures */ pdcs->regs = (struct pdc_regs *)pdcs->pdc_reg_vbase; pdcs->txregs_64 = (struct dma64_regs *) (((u8 *)pdcs->pdc_reg_vbase) + PDC_TXREGS_OFFSET + (sizeof(struct dma64) * ringset)); pdcs->rxregs_64 = (struct dma64_regs *) (((u8 *)pdcs->pdc_reg_vbase) + PDC_RXREGS_OFFSET + (sizeof(struct dma64) * ringset)); pdcs->ntxd = PDC_RING_ENTRIES; pdcs->nrxd = PDC_RING_ENTRIES; pdcs->ntxpost = PDC_RING_ENTRIES - 1; pdcs->nrxpost = PDC_RING_ENTRIES - 1; iowrite32(0, &pdcs->regs->intmask); dma_reg = &pdcs->regs->dmaregs[ringset]; /* Configure DMA but will enable later in pdc_ring_init() */ iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control); iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1), &dma_reg->dmarcv.control); /* Reset current index pointers after making sure DMA is disabled */ iowrite32(0, &dma_reg->dmaxmt.ptr); iowrite32(0, &dma_reg->dmarcv.ptr); if (pdcs->pdc_resp_hdr_len == PDC_SPU2_RESP_HDR_LEN) iowrite32(PDC_CKSUM_CTRL, pdcs->pdc_reg_vbase + PDC_CKSUM_CTRL_OFFSET); } /** * pdc_hw_disable() - Disable the tx and rx control in the hw. * @pdcs: PDC state structure * */ static void pdc_hw_disable(struct pdc_state *pdcs) { struct dma64 *dma_reg; dma_reg = &pdcs->regs->dmaregs[PDC_RINGSET]; iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control); iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1), &dma_reg->dmarcv.control); } /** * pdc_rx_buf_pool_create() - Pool of receive buffers used to catch the metadata * header returned with each response message. * @pdcs: PDC state structure * * The metadata is not returned to the mailbox client. So the PDC driver * manages these buffers. * * Return: PDC_SUCCESS * -ENOMEM if pool creation fails */ static int pdc_rx_buf_pool_create(struct pdc_state *pdcs) { struct platform_device *pdev; struct device *dev; pdev = pdcs->pdev; dev = &pdev->dev; pdcs->pdc_resp_hdr_len = pdcs->rx_status_len; if (pdcs->use_bcm_hdr) pdcs->pdc_resp_hdr_len += BCM_HDR_LEN; pdcs->rx_buf_pool = dma_pool_create("pdc rx bufs", dev, pdcs->pdc_resp_hdr_len, RX_BUF_ALIGN, 0); if (!pdcs->rx_buf_pool) return -ENOMEM; return PDC_SUCCESS; } /** * pdc_interrupts_init() - Initialize the interrupt configuration for a PDC and * specify a threaded IRQ handler for deferred handling of interrupts outside of * interrupt context. * @pdcs: PDC state * * Set the interrupt mask for transmit and receive done. * Set the lazy interrupt frame count to generate an interrupt for just one pkt. * * Return: PDC_SUCCESS * <0 if threaded irq request fails */ static int pdc_interrupts_init(struct pdc_state *pdcs) { struct platform_device *pdev = pdcs->pdev; struct device *dev = &pdev->dev; struct device_node *dn = pdev->dev.of_node; int err; /* interrupt configuration */ iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET); if (pdcs->hw_type == FA_HW) iowrite32(PDC_LAZY_INT, pdcs->pdc_reg_vbase + FA_RCVLAZY0_OFFSET); else iowrite32(PDC_LAZY_INT, pdcs->pdc_reg_vbase + PDC_RCVLAZY0_OFFSET); /* read irq from device tree */ pdcs->pdc_irq = irq_of_parse_and_map(dn, 0); dev_dbg(dev, "pdc device %s irq %u for pdcs %p", dev_name(dev), pdcs->pdc_irq, pdcs); err = devm_request_irq(dev, pdcs->pdc_irq, pdc_irq_handler, 0, dev_name(dev), dev); if (err) { dev_err(dev, "IRQ %u request failed with err %d\n", pdcs->pdc_irq, err); return err; } return PDC_SUCCESS; } static const struct mbox_chan_ops pdc_mbox_chan_ops = { .send_data = pdc_send_data, .last_tx_done = pdc_last_tx_done, .startup = pdc_startup, .shutdown = pdc_shutdown }; /** * pdc_mb_init() - Initialize the mailbox controller. * @pdcs: PDC state * * Each PDC is a mailbox controller. Each ringset is a mailbox channel. Kernel * driver only uses one ringset and thus one mb channel. PDC uses the transmit * complete interrupt to determine when a mailbox message has successfully been * transmitted. * * Return: 0 on success * < 0 if there is an allocation or registration failure */ static int pdc_mb_init(struct pdc_state *pdcs) { struct device *dev = &pdcs->pdev->dev; struct mbox_controller *mbc; int chan_index; int err; mbc = &pdcs->mbc; mbc->dev = dev; mbc->ops = &pdc_mbox_chan_ops; mbc->num_chans = 1; mbc->chans = devm_kcalloc(dev, mbc->num_chans, sizeof(*mbc->chans), GFP_KERNEL); if (!mbc->chans) return -ENOMEM; mbc->txdone_irq = false; mbc->txdone_poll = true; mbc->txpoll_period = 1; for (chan_index = 0; chan_index < mbc->num_chans; chan_index++) mbc->chans[chan_index].con_priv = pdcs; /* Register mailbox controller */ err = devm_mbox_controller_register(dev, mbc); if (err) { dev_crit(dev, "Failed to register PDC mailbox controller. Error %d.", err); return err; } return 0; } /* Device tree API */ static const int pdc_hw = PDC_HW; static const int fa_hw = FA_HW; static const struct of_device_id pdc_mbox_of_match[] = { {.compatible = "brcm,iproc-pdc-mbox", .data = &pdc_hw}, {.compatible = "brcm,iproc-fa2-mbox", .data = &fa_hw}, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, pdc_mbox_of_match); /** * pdc_dt_read() - Read application-specific data from device tree. * @pdev: Platform device * @pdcs: PDC state * * Reads the number of bytes of receive status that precede each received frame. * Reads whether transmit and received frames should be preceded by an 8-byte * BCM header. * * Return: 0 if successful * -ENODEV if device not available */ static int pdc_dt_read(struct platform_device *pdev, struct pdc_state *pdcs) { struct device *dev = &pdev->dev; struct device_node *dn = pdev->dev.of_node; const struct of_device_id *match; const int *hw_type; int err; err = of_property_read_u32(dn, "brcm,rx-status-len", &pdcs->rx_status_len); if (err < 0) dev_err(dev, "%s failed to get DMA receive status length from device tree", __func__); pdcs->use_bcm_hdr = of_property_read_bool(dn, "brcm,use-bcm-hdr"); pdcs->hw_type = PDC_HW; match = of_match_device(of_match_ptr(pdc_mbox_of_match), dev); if (match != NULL) { hw_type = match->data; pdcs->hw_type = *hw_type; } return 0; } /** * pdc_probe() - Probe function for PDC driver. * @pdev: PDC platform device * * Reserve and map register regions defined in device tree. * Allocate and initialize tx and rx DMA rings. * Initialize a mailbox controller for each PDC. * * Return: 0 if successful * < 0 if an error */ static int pdc_probe(struct platform_device *pdev) { int err = 0; struct device *dev = &pdev->dev; struct resource *pdc_regs; struct pdc_state *pdcs; /* PDC state for one SPU */ pdcs = devm_kzalloc(dev, sizeof(*pdcs), GFP_KERNEL); if (!pdcs) { err = -ENOMEM; goto cleanup; } pdcs->pdev = pdev; platform_set_drvdata(pdev, pdcs); pdcs->pdc_idx = pdcg.num_spu; pdcg.num_spu++; err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(39)); if (err) { dev_warn(dev, "PDC device cannot perform DMA. Error %d.", err); goto cleanup; } /* Create DMA pool for tx ring */ pdcs->ring_pool = dma_pool_create("pdc rings", dev, PDC_RING_SIZE, RING_ALIGN, 0); if (!pdcs->ring_pool) { err = -ENOMEM; goto cleanup; } err = pdc_dt_read(pdev, pdcs); if (err) goto cleanup_ring_pool; pdc_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!pdc_regs) { err = -ENODEV; goto cleanup_ring_pool; } dev_dbg(dev, "PDC register region res.start = %pa, res.end = %pa", &pdc_regs->start, &pdc_regs->end); pdcs->pdc_reg_vbase = devm_ioremap_resource(&pdev->dev, pdc_regs); if (IS_ERR(pdcs->pdc_reg_vbase)) { err = PTR_ERR(pdcs->pdc_reg_vbase); goto cleanup_ring_pool; } /* create rx buffer pool after dt read to know how big buffers are */ err = pdc_rx_buf_pool_create(pdcs); if (err) goto cleanup_ring_pool; pdc_hw_init(pdcs); /* Init tasklet for deferred DMA rx processing */ tasklet_setup(&pdcs->rx_tasklet, pdc_tasklet_cb); err = pdc_interrupts_init(pdcs); if (err) goto cleanup_buf_pool; /* Initialize mailbox controller */ err = pdc_mb_init(pdcs); if (err) goto cleanup_buf_pool; pdc_setup_debugfs(pdcs); dev_dbg(dev, "pdc_probe() successful"); return PDC_SUCCESS; cleanup_buf_pool: tasklet_kill(&pdcs->rx_tasklet); dma_pool_destroy(pdcs->rx_buf_pool); cleanup_ring_pool: dma_pool_destroy(pdcs->ring_pool); cleanup: return err; } static int pdc_remove(struct platform_device *pdev) { struct pdc_state *pdcs = platform_get_drvdata(pdev); pdc_free_debugfs(); tasklet_kill(&pdcs->rx_tasklet); pdc_hw_disable(pdcs); dma_pool_destroy(pdcs->rx_buf_pool); dma_pool_destroy(pdcs->ring_pool); return 0; } static struct platform_driver pdc_mbox_driver = { .probe = pdc_probe, .remove = pdc_remove, .driver = { .name = "brcm-iproc-pdc-mbox", .of_match_table = of_match_ptr(pdc_mbox_of_match), }, }; module_platform_driver(pdc_mbox_driver); MODULE_AUTHOR("Rob Rice <rob.rice@broadcom.com>"); MODULE_DESCRIPTION("Broadcom PDC mailbox driver"); MODULE_LICENSE("GPL v2");