From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752486AbcF1Nh1 (ORCPT ); Tue, 28 Jun 2016 09:37:27 -0400 Received: from mail-qk0-f174.google.com ([209.85.220.174]:35443 "EHLO mail-qk0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752091AbcF1NhY (ORCPT ); Tue, 28 Jun 2016 09:37:24 -0400 MIME-Version: 1.0 In-Reply-To: References: <1464113250-15629-1-git-send-email-rob.rice@broadcom.com> <1464113250-15629-3-git-send-email-rob.rice@broadcom.com> From: Rob Rice Date: Tue, 28 Jun 2016 09:36:59 -0400 Message-ID: Subject: Re: [PATCH 2/3] mailbox: Add Broadcom PDC mailbox driver To: Jassi Brar Cc: Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Devicetree List , "linux-arm-kernel@lists.infradead.org" , BCM Kernel Feedback , Linux Kernel Mailing List , Ray Jui , Scott Branden , Jon Mason , Florian Fainelli , Anup Patel , Catalin Marinas , Will Deacon , Rob Rice Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jassi, Thanks for the comments. Replies below. Rob On Sun, Jun 26, 2016 at 2:31 AM, Jassi Brar wrote: > On Tue, May 24, 2016 at 11:37 PM, Rob Rice wrote: >> From: Rob Rice >> >> The Broadcom PDC mailbox driver is a mailbox controller that >> manages data transfers to and from one or more offload engines. >> >> Signed-off-by: Rob Rice >> Reviewed-by: Scott Branden >> Reviewed-by: Ray Jui >> --- >> drivers/mailbox/Kconfig | 9 + >> drivers/mailbox/Makefile | 2 + >> drivers/mailbox/mailbox-pdc/Makefile | 8 + >> drivers/mailbox/mailbox-pdc/pdc.c | 1181 +++++++++++++++++++++++++++++++ >> drivers/mailbox/mailbox-pdc/pdc.h | 303 ++++++++ >> drivers/mailbox/mailbox-pdc/pdc_debug.c | 101 +++ >> drivers/mailbox/mailbox-pdc/pdc_debug.h | 24 + >> > We already have mailbox api testing rig - mailbox-test, still if you > really need debugfs exposure please merge it in pdc.c especially when > pdc_debug.c is only 80lines and it always compiled and currently has > to export functions globally. Maybe fold everything in a single like > other platforms? [WRR] I'm using debugfs to display stats, not so much for testing the module. So I don't think mailbox-test is a substitute. But if you prefer, I'll move the stats code into pdc.c, along with the code from pdc.h and move pdc.c from the mailbox-pdc directory up to drivers/mailbox. > >> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig >> index 5305923..19c8c9a 100644 >> --- a/drivers/mailbox/Kconfig >> +++ b/drivers/mailbox/Kconfig >> @@ -123,4 +123,13 @@ config XGENE_SLIMPRO_MBOX >> It is used to send short messages between ARM64-bit cores and >> the SLIMpro Management Engine, primarily for PM. Say Y here if you >> want to use the APM X-Gene SLIMpro IPCM support. >> + >> +config BCM_PDC_MBOX >> + tristate "Broadcom PDC Mailbox" >> + depends on ARM64 >> + default ARCH_BCM_IPROC >> + help >> + Mailbox implementation for the Broadcom PDC ring manager, >> + which provides access to various offload engines on Broadcom >> + SoCs. Say Y here if you want to use the Broadcom PDC. >> endif >> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >> index 0be3e74..2c14a03 100644 >> --- a/drivers/mailbox/Makefile >> +++ b/drivers/mailbox/Makefile >> @@ -25,3 +25,5 @@ obj-$(CONFIG_TI_MESSAGE_MANAGER) += ti-msgmgr.o >> obj-$(CONFIG_XGENE_SLIMPRO_MBOX) += mailbox-xgene-slimpro.o >> >> obj-$(CONFIG_HI6220_MBOX) += hi6220-mailbox.o >> + >> +obj-$(CONFIG_BCM_PDC_MBOX) += mailbox-pdc/ >> diff --git a/drivers/mailbox/mailbox-pdc/Makefile b/drivers/mailbox/mailbox-pdc/Makefile >> new file mode 100644 >> index 0000000..5dc78c3 >> --- /dev/null >> +++ b/drivers/mailbox/mailbox-pdc/Makefile >> @@ -0,0 +1,8 @@ >> +# Makefile for Broadcom PDC Mailbox driver >> + >> +# Uncomment to enable debug tracing in the PDC driver >> +# CFLAGS_pdc.o := -DDEBUG >> +# CFLAGS_pdc_debug.o := -DDEBUG >> + >> +pdc-mbox-objs := pdc.o pdc_debug.o >> +obj-$(CONFIG_BCM_PDC_MBOX) := pdc-mbox.o >> diff --git a/drivers/mailbox/mailbox-pdc/pdc.c b/drivers/mailbox/mailbox-pdc/pdc.c >> new file mode 100644 >> index 0000000..1c24ea8 >> --- /dev/null >> +++ b/drivers/mailbox/mailbox-pdc/pdc.c >> @@ -0,0 +1,1181 @@ >> +/* >> + * Copyright 2016 Broadcom >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License, version 2, as >> + * published by the Free Software Foundation (the "GPL"). >> + * >> + * This program is distributed in the hope that it will be useful, but >> + * WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU >> + * General Public License version 2 (GPLv2) for more details. >> + * >> + * You should have received a copy of the GNU General Public License >> + * version 2 (GPLv2) along with this source code. >> + */ >> + >> +/* >> + * 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. >> + * >> + * 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 >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#include "pdc.h" >> +#include "pdc_debug.h" >> + >> +/* 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_XMTINT_0 (24 + PDC_RINGSET) >> +#define PDC_RCVINT_0 (16 + PDC_RINGSET) >> +#define PDC_XMTINTEN_0 BIT(PDC_XMTINT_0) >> +#define PDC_RCVINTEN_0 BIT(PDC_RCVINT_0) >> +#define PDC_INTMASK (PDC_XMTINTEN_0 | 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) >> + >> +/* >> + * 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: >> + * 0 - XmtEn - enable activity on the tx channel >> + * 11 - PtyChkDisable - parity check is disabled >> + * 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory >> + */ >> +#define PDC_TX_CTL 0x000C0801 >> + >> +/* >> + * Sets the following bits for write to receive control reg: >> + * 0 - RcvEn - enable activity on the rx channel >> + * 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 0x000C0E01 >> + >> +#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 >> + >> +/* Global variables */ >> + >> +struct pdc_globals { >> + /* Actual number of SPUs in hardware, as reported by device tree */ >> + u32 num_spu; >> +}; >> + >> +static struct pdc_globals pdcg; >> + >> +/** >> + * 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; >> + >> + 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); >> + >> + iowrite32(lower_32_bits(dma_addr), >> + (void *)&pdcs->rxd_64[pdcs->rxout].addrlow); >> + iowrite32(upper_32_bits(dma_addr), >> + (void *)&pdcs->rxd_64[pdcs->rxout].addrhigh); >> + iowrite32(flags, (void *)&pdcs->rxd_64[pdcs->rxout].ctrl1); >> + iowrite32(buf_len, (void *)&pdcs->rxd_64[pdcs->rxout].ctrl2); >> + /* 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; >> + >> + 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); >> + >> + iowrite32(lower_32_bits(dma_addr), >> + (void *)&pdcs->txd_64[pdcs->txout].addrlow); >> + iowrite32(upper_32_bits(dma_addr), >> + (void *)&pdcs->txd_64[pdcs->txout].addrhigh); >> + iowrite32(flags, (void *)&pdcs->txd_64[pdcs->txout].ctrl1); >> + iowrite32(buf_len, (void *)&pdcs->txd_64[pdcs->txout].ctrl2); >> + >> + /* bump ring index and return */ >> + pdcs->txout = NEXTTXD(pdcs->txout, pdcs->ntxpost); >> +} >> + >> +/** >> + * pdc_receive() - Receive a response message from a given SPU. >> + * @pdcs: PDC state for the SPU to receive from >> + * @mssg: mailbox message to be returned to client >> + * >> + * When the return code indicates success, the response message is available in >> + * the receive buffers provided prior to submission of the request. >> + * >> + * Input: >> + * pdcs - PDC state structure for the SPU to be polled >> + * mssg - mailbox message to be returned to client. This function sets the >> + * context pointer on the message to help the client associate the >> + * response with a 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(struct pdc_state *pdcs, struct brcm_message *mssg) >> +{ >> + struct device *dev = &pdcs->pdev->dev; >> + u32 len, rx_status; >> + u32 num_frags; >> + int i; >> + 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; >> + >> + spin_lock(&pdcs->pdc_lock); >> + >> + /* >> + * 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->rxin_numd[pdcs->rxin])) { >> + /* See if the hw has written more fragments than we know */ >> + pdcs->last_rx_curr = >> + (ioread32((void *)&pdcs->rxregs_64->status0) & >> + CRYPTO_D64_RS0_CD_MASK) / RING_ENTRY_SIZE; >> + frags_rdy = NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, >> + pdcs->nrxpost); >> + if ((frags_rdy == 0) || >> + (frags_rdy < pdcs->rxin_numd[pdcs->rxin])) { >> + /* No response ready */ >> + spin_unlock(&pdcs->pdc_lock); >> + return -EAGAIN; >> + } >> + /* can't read descriptors/data until write index is read */ >> + rmb(); >> + } >> + >> + num_frags = pdcs->txin_numd[pdcs->txin]; >> + dma_unmap_sg(dev, pdcs->src_sg[pdcs->txin], >> + sg_nents(pdcs->src_sg[pdcs->txin]), DMA_TO_DEVICE); >> + >> + for (i = 0; i < num_frags; i++) >> + pdcs->txin = NEXTTXD(pdcs->txin, pdcs->ntxpost); >> + >> + dev_dbg(dev, "PDC %u reclaimed %d tx descriptors", >> + pdcs->pdc_idx, num_frags); >> + >> + rx_idx = pdcs->rxin; >> + num_frags = pdcs->rxin_numd[rx_idx]; >> + /* Return opaque context with result */ >> + mssg->ctx = pdcs->rxp_ctx[rx_idx]; >> + pdcs->rxp_ctx[rx_idx] = NULL; >> + resp_hdr = pdcs->resp_hdr[rx_idx]; >> + resp_hdr_daddr = pdcs->resp_hdr_daddr[rx_idx]; >> + dma_unmap_sg(dev, pdcs->dst_sg[rx_idx], >> + sg_nents(pdcs->dst_sg[rx_idx]), DMA_FROM_DEVICE); >> + >> + for (i = 0; i < num_frags; i++) >> + pdcs->rxin = NEXTRXD(pdcs->rxin, pdcs->nrxpost); >> + >> + spin_unlock(&pdcs->pdc_lock); >> + >> + 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); >> + >> + pdcs->pdc_replies++; >> + /* if we read one or more rx descriptors, claim success */ >> + if (num_frags > 0) >> + return PDC_SUCCESS; >> + else >> + return -EIO; >> +} >> + >> +/** >> + * 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, (void *)&pdcs->rxregs_64->ptr); >> + iowrite32(pdcs->txout << 4, (void *)&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; >> + >> + 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 (!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->rxin_numd[pdcs->rx_msg_start] = 1; >> + >> + if (unlikely(pdcs->rxout == (pdcs->nrxd - 1))) >> + flags |= D64_CTRL1_EOT; >> + >> + pdcs->rxp_ctx[pdcs->rxout] = ctx; >> + pdcs->dst_sg[pdcs->rxout] = dst_sg; >> + pdcs->resp_hdr[pdcs->rxout] = vaddr; >> + pdcs->resp_hdr_daddr[pdcs->rxout] = 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->rxin_numd[pdcs->rx_msg_start] += desc_w; >> + >> + return PDC_SUCCESS; >> +} >> + >> +/** >> + * pdc_irq_handler() - Interrupt handler called in interrupt context. >> + * @irq: Interrupt number that has fired >> + * @cookie: PDC state 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 *cookie) >> +{ >> + struct pdc_state *pdcs = cookie; >> + u32 intstatus = ioread32(pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET); >> + >> + if (intstatus & PDC_XMTINTEN_0) >> + set_bit(PDC_XMTINT_0, &pdcs->intstatus); >> + if (intstatus & PDC_RCVINTEN_0) >> + set_bit(PDC_RCVINT_0, &pdcs->intstatus); >> + >> + /* Clear interrupt flags in device */ >> + iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET); >> + >> + /* Wakeup IRQ thread */ >> + if (pdcs && (irq == pdcs->pdc_irq) && (intstatus & PDC_INTMASK)) >> + return IRQ_WAKE_THREAD; >> + >> + return IRQ_NONE; >> +} >> + >> +/** >> + * pdc_irq_thread() - Function invoked on deferred thread when a DMA tx has >> + * completed or data is available to receive. >> + * @irq: Interrupt number >> + * @cookie: PDC state for PDC that generated the interrupt >> + * >> + * On DMA tx complete, notify the mailbox client. On DMA rx complete, process >> + * as many SPU response messages as are available and send each to the mailbox >> + * client. >> + * >> + * Return: IRQ_HANDLED if we recognized and handled the interrupt >> + * IRQ_NONE otherwise >> + */ >> +static irqreturn_t pdc_irq_thread(int irq, void *cookie) >> +{ >> + struct pdc_state *pdcs = cookie; >> + struct mbox_controller *mbc; >> + struct mbox_chan *chan; >> + bool tx_int; >> + bool rx_int; >> + int rx_status; >> + struct brcm_message mssg; >> + >> + tx_int = test_and_clear_bit(PDC_XMTINT_0, &pdcs->intstatus); >> + rx_int = test_and_clear_bit(PDC_RCVINT_0, &pdcs->intstatus); >> + >> + if (pdcs && (tx_int || rx_int)) { >> + dev_dbg(&pdcs->pdev->dev, >> + "%s() got irq %d with tx_int %s, rx_int %s", >> + __func__, irq, >> + tx_int ? "set" : "clear", rx_int ? "set" : "clear"); >> + >> + mbc = &pdcs->mbc; >> + chan = &mbc->chans[0]; >> + >> + if (tx_int) { >> + dev_dbg(&pdcs->pdev->dev, "%s(): tx done", __func__); >> + /* only one frame in flight at a time */ >> + mbox_chan_txdone(chan, PDC_SUCCESS); >> + } >> + if (rx_int) { >> + while (1) { >> + /* Could be many frames ready */ >> + memset(&mssg, 0, sizeof(mssg)); >> + mssg.type = BRCM_MESSAGE_SPU; >> + rx_status = pdc_receive(pdcs, &mssg); >> + if (rx_status >= 0) { >> + dev_dbg(&pdcs->pdev->dev, >> + "%s(): invoking client rx cb", >> + __func__); >> + mbox_chan_received_data(chan, &mssg); >> + } else { >> + dev_dbg(&pdcs->pdev->dev, >> + "%s(): no SPU response available", >> + __func__); >> + break; >> + } >> + } >> + } >> + return IRQ_HANDLED; >> + } >> + return IRQ_NONE; >> +} >> + >> +/** >> + * 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 (!tx.vbase) { >> + err = -ENOMEM; >> + goto done; >> + } >> + >> + /* Allocate rx ring */ >> + rx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &rx.dmabase); >> + if (!rx.vbase) { >> + err = -ENOMEM; >> + goto fail_dealloc; >> + } >> + >> + dev_dbg(dev, " - base DMA addr of tx ring %#llx", tx.dmabase); >> + dev_dbg(dev, " - base virtual addr of tx ring %p", tx.vbase); >> + dev_dbg(dev, " - base DMA addr of rx ring %#llx", rx.dmabase); >> + dev_dbg(dev, " - base virtual addr of rx ring %p", rx.vbase); >> + >> + /* lock after ring allocation to avoid scheduling while atomic */ >> + spin_lock(&pdcs->pdc_lock); >> + >> + 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]; >> + iowrite32(lower_32_bits(pdcs->tx_ring_alloc.dmabase), >> + (void *)&dma_reg->dmaxmt.addrlow); >> + iowrite32(upper_32_bits(pdcs->tx_ring_alloc.dmabase), >> + (void *)&dma_reg->dmaxmt.addrhigh); >> + >> + iowrite32(lower_32_bits(pdcs->rx_ring_alloc.dmabase), >> + (void *)&dma_reg->dmarcv.addrlow); >> + iowrite32(upper_32_bits(pdcs->rx_ring_alloc.dmabase), >> + (void *)&dma_reg->dmarcv.addrhigh); >> + >> + /* 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, >> + (void *)&pdcs->txd_64[i].ctrl1); >> + } else { >> + /* Last descriptor in ringset. Set End of Table. */ >> + iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOF | >> + D64_CTRL1_EOT, >> + (void *)&pdcs->txd_64[i].ctrl1); >> + } >> + >> + /* Every rx descriptor can be used for start of frame */ >> + if (i != pdcs->nrxpost) { >> + iowrite32(D64_CTRL1_SOF, >> + (void *)&pdcs->rxd_64[i].ctrl1); >> + } else { >> + /* Last descriptor in ringset. Set End of Table. */ >> + iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOT, >> + (void *)&pdcs->rxd_64[i].ctrl1); >> + } >> + } >> + spin_unlock(&pdcs->pdc_lock); >> + 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_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; >> + >> + if (mssg->type != BRCM_MESSAGE_SPU) >> + return -ENOTSUPP; >> + >> + src_nent = sg_nents(mssg->spu.src); >> + if (src_nent) { >> + nent = dma_map_sg(dev, mssg->spu.src, src_nent, DMA_TO_DEVICE); >> + if (nent == 0) >> + return -EIO; >> + } >> + >> + dst_nent = sg_nents(mssg->spu.dst); >> + if (dst_nent) { >> + nent = dma_map_sg(dev, mssg->spu.dst, dst_nent, >> + DMA_FROM_DEVICE); >> + if (nent == 0) { >> + dma_unmap_sg(dev, mssg->spu.src, src_nent, >> + DMA_TO_DEVICE); >> + return -EIO; >> + } >> + } >> + >> + spin_lock(&pdcs->pdc_lock); >> + >> + /* 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 */ >> + >> + spin_unlock(&pdcs->pdc_lock); >> + >> + if (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) >> + 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. >> + * @dev: device structure for PDC >> + * @pdcs: state of the PDC >> + * @parms: parameter values to set >> + */ >> +static >> +void pdc_hw_init(struct device *dev, struct pdc_state *pdcs, >> + struct hw_init_parms *parms) >> > You could do without the dev and parms. [WRR] Yes, I can get dev from pdcs. but parms is a stack variable in the calling function and has to be passed, as I see it. > >> +{ >> + struct dma64 *dma_reg; >> + >> + int ringset = PDC_RINGSET; >> + >> + dev_dbg(dev, "PDC %u initial values:", pdcs->pdc_idx); >> + dev_dbg(dev, "state structure: %p", >> + pdcs); >> + dev_dbg(dev, " - base physical addr of hw regs %#llx", >> + parms->hw_pbase); >> + dev_dbg(dev, " - base virtual addr of hw regs %p", >> + parms->hw_vbase); >> + >> + /* initialize data structures */ >> + pdcs->regs = (struct pdc_regs *)parms->hw_vbase; >> + pdcs->txregs_64 = (struct dma64_regs *) >> + (void *)(((u8 *)parms->hw_vbase) + >> + PDC_TXREGS_OFFSET + (sizeof(struct dma64) * ringset)); >> + pdcs->rxregs_64 = (struct dma64_regs *) >> + (void *)(((u8 *)parms->hw_vbase) + >> + PDC_RXREGS_OFFSET + (sizeof(struct dma64) * ringset)); >> + >> + pdcs->ntxd = parms->ring_entries; >> + pdcs->nrxd = parms->ring_entries; >> + pdcs->ntxpost = parms->ring_entries - 1; >> + pdcs->nrxpost = parms->ring_entries - 1; >> + pdcs->regs->intmask = 0; >> + >> + dma_reg = &pdcs->regs->dmaregs[ringset]; >> + iowrite32(0, (void *)&dma_reg->dmaxmt.ptr); >> + iowrite32(0, (void *)&dma_reg->dmarcv.ptr); >> + >> + iowrite32(PDC_TX_CTL, (void *)&dma_reg->dmaxmt.control); >> + >> + iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1), >> + (void *)&dma_reg->dmarcv.control); >> + >> + if (pdcs->pdc_resp_hdr_len == PDC_SPU2_RESP_HDR_LEN) >> + iowrite32(PDC_CKSUM_CTRL, >> + pdcs->pdc_reg_vbase + PDC_CKSUM_CTRL_OFFSET); >> +} >> + >> +/** >> + * pdc_rx_buf_pool_create() - Pool of receive buffers used to catch the metadata >> + * header returned with each response message. >> + * @dev: device structure >> + * @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 device *dev, struct pdc_state *pdcs) >> +{ >> + 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. >> + * @pdev: platform device >> + * @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 platform_device *pdev, >> + struct pdc_state *pdcs) >> +{ >> + struct device *dev = &pdev->dev; >> + struct device_node *dn = pdev->dev.of_node; >> + int err; >> + >> + pdcs->intstatus = 0; >> + >> + /* interrupt configuration */ >> + iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET); >> + 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_threaded_irq(dev, pdcs->pdc_irq, >> + pdc_irq_handler, >> + pdc_irq_thread, 0, dev_name(dev), pdcs); >> + if (err) { >> + dev_err(dev, "threaded tx 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, >> + .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 = true; >> + mbc->txdone_poll = false; >> + for (chan_index = 0; chan_index < mbc->num_chans; chan_index++) >> + mbc->chans[chan_index].con_priv = pdcs; >> + >> + /* Register mailbox controller */ >> + err = mbox_controller_register(mbc); >> + if (err) { >> + dev_crit(dev, >> + "Failed to register PDC mailbox controller. Error %d.", >> + err); >> + return err; >> + } >> + return 0; >> +} >> + >> +/** >> + * 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; >> + 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"); >> + >> + 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; >> + struct hw_init_parms hw_parms; /* params for initializing spu-dma */ >> + >> + /* PDC state for one SPU */ >> + pdcs = devm_kzalloc(dev, sizeof(*pdcs), GFP_KERNEL); >> + if (!pdcs) { >> + err = -ENOMEM; >> + goto cleanup; >> + } >> + >> + spin_lock_init(&pdcs->pdc_lock); >> + 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(32)); >> + 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 = %#llx, res.end = %#llx", >> + 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); >> + dev_err(&pdev->dev, "Failed to map registers: %d\n", err); >> + goto cleanup_ring_pool; >> + } >> + >> + /* create rx buffer pool after dt read to know how big buffers are */ >> + err = pdc_rx_buf_pool_create(dev, pdcs); > 'dev' argument could be omitted. [WRR] Yes, I can do that. > >> + if (err) >> + goto cleanup_ring_pool; >> + >> + hw_parms.hw_pbase = (dma_addr_t)(pdc_regs->start); >> + hw_parms.hw_vbase = pdcs->pdc_reg_vbase; >> + >> + hw_parms.ring_entries = PDC_RING_ENTRIES; >> + >> + pdc_hw_init(dev, pdcs, &hw_parms); > 'dev' and 'hw_parms' argument could be omitted. [WRR] Removed dev. > >> + >> + err = pdc_interrupts_init(pdev, pdcs); > 'pdev' argument could be omitted. [WRR] OK. > > > thanks.