--- /dev/null
+/* Broadcom FlexRM Mailbox Driver
+ *
+ * Copyright (C) 2017 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.
+ *
+ * Each Broadcom FlexSparx4 offload engine is implemented as an
+ * extension to Broadcom FlexRM ring manager. The FlexRM ring
+ * manager provides a set of rings which can be used to submit
+ * work to a FlexSparx4 offload engine.
+ *
+ * This driver creates a mailbox controller using a set of FlexRM
+ * rings where each mailbox channel represents a separate FlexRM ring.
+ */
+
+#include <asm/barrier.h>
+#include <asm/byteorder.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/err.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox/brcm-message.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+/* ====== FlexRM register defines ===== */
+
+/* FlexRM configuration */
+#define RING_REGS_SIZE 0x10000
+#define RING_DESC_SIZE 8
+#define RING_DESC_INDEX(offset) \
+ ((offset) / RING_DESC_SIZE)
+#define RING_DESC_OFFSET(index) \
+ ((index) * RING_DESC_SIZE)
+#define RING_MAX_REQ_COUNT 1024
+#define RING_BD_ALIGN_ORDER 12
+#define RING_BD_ALIGN_CHECK(addr) \
+ (!((addr) & ((0x1 << RING_BD_ALIGN_ORDER) - 1)))
+#define RING_BD_TOGGLE_INVALID(offset) \
+ (((offset) >> RING_BD_ALIGN_ORDER) & 0x1)
+#define RING_BD_TOGGLE_VALID(offset) \
+ (!RING_BD_TOGGLE_INVALID(offset))
+#define RING_BD_DESC_PER_REQ 32
+#define RING_BD_DESC_COUNT \
+ (RING_MAX_REQ_COUNT * RING_BD_DESC_PER_REQ)
+#define RING_BD_SIZE \
+ (RING_BD_DESC_COUNT * RING_DESC_SIZE)
+#define RING_CMPL_ALIGN_ORDER 13
+#define RING_CMPL_DESC_COUNT RING_MAX_REQ_COUNT
+#define RING_CMPL_SIZE \
+ (RING_CMPL_DESC_COUNT * RING_DESC_SIZE)
+#define RING_VER_MAGIC 0x76303031
+
+/* Per-Ring register offsets */
+#define RING_VER 0x000
+#define RING_BD_START_ADDR 0x004
+#define RING_BD_READ_PTR 0x008
+#define RING_BD_WRITE_PTR 0x00c
+#define RING_BD_READ_PTR_DDR_LS 0x010
+#define RING_BD_READ_PTR_DDR_MS 0x014
+#define RING_CMPL_START_ADDR 0x018
+#define RING_CMPL_WRITE_PTR 0x01c
+#define RING_NUM_REQ_RECV_LS 0x020
+#define RING_NUM_REQ_RECV_MS 0x024
+#define RING_NUM_REQ_TRANS_LS 0x028
+#define RING_NUM_REQ_TRANS_MS 0x02c
+#define RING_NUM_REQ_OUTSTAND 0x030
+#define RING_CONTROL 0x034
+#define RING_FLUSH_DONE 0x038
+#define RING_MSI_ADDR_LS 0x03c
+#define RING_MSI_ADDR_MS 0x040
+#define RING_MSI_CONTROL 0x048
+#define RING_BD_READ_PTR_DDR_CONTROL 0x04c
+#define RING_MSI_DATA_VALUE 0x064
+
+/* Register RING_BD_START_ADDR fields */
+#define BD_LAST_UPDATE_HW_SHIFT 28
+#define BD_LAST_UPDATE_HW_MASK 0x1
+#define BD_START_ADDR_VALUE(pa) \
+ ((u32)((((dma_addr_t)(pa)) >> RING_BD_ALIGN_ORDER) & 0x0fffffff))
+#define BD_START_ADDR_DECODE(val) \
+ ((dma_addr_t)((val) & 0x0fffffff) << RING_BD_ALIGN_ORDER)
+
+/* Register RING_CMPL_START_ADDR fields */
+#define CMPL_START_ADDR_VALUE(pa) \
+ ((u32)((((u64)(pa)) >> RING_CMPL_ALIGN_ORDER) & 0x03ffffff))
+
+/* Register RING_CONTROL fields */
+#define CONTROL_MASK_DISABLE_CONTROL 12
+#define CONTROL_FLUSH_SHIFT 5
+#define CONTROL_ACTIVE_SHIFT 4
+#define CONTROL_RATE_ADAPT_MASK 0xf
+#define CONTROL_RATE_DYNAMIC 0x0
+#define CONTROL_RATE_FAST 0x8
+#define CONTROL_RATE_MEDIUM 0x9
+#define CONTROL_RATE_SLOW 0xa
+#define CONTROL_RATE_IDLE 0xb
+
+/* Register RING_FLUSH_DONE fields */
+#define FLUSH_DONE_MASK 0x1
+
+/* Register RING_MSI_CONTROL fields */
+#define MSI_TIMER_VAL_SHIFT 16
+#define MSI_TIMER_VAL_MASK 0xffff
+#define MSI_ENABLE_SHIFT 15
+#define MSI_ENABLE_MASK 0x1
+#define MSI_COUNT_SHIFT 0
+#define MSI_COUNT_MASK 0x3ff
+
+/* Register RING_BD_READ_PTR_DDR_CONTROL fields */
+#define BD_READ_PTR_DDR_TIMER_VAL_SHIFT 16
+#define BD_READ_PTR_DDR_TIMER_VAL_MASK 0xffff
+#define BD_READ_PTR_DDR_ENABLE_SHIFT 15
+#define BD_READ_PTR_DDR_ENABLE_MASK 0x1
+
+/* ====== FlexRM ring descriptor defines ===== */
+
+/* Completion descriptor format */
+#define CMPL_OPAQUE_SHIFT 0
+#define CMPL_OPAQUE_MASK 0xffff
+#define CMPL_ENGINE_STATUS_SHIFT 16
+#define CMPL_ENGINE_STATUS_MASK 0xffff
+#define CMPL_DME_STATUS_SHIFT 32
+#define CMPL_DME_STATUS_MASK 0xffff
+#define CMPL_RM_STATUS_SHIFT 48
+#define CMPL_RM_STATUS_MASK 0xffff
+
+/* Completion DME status code */
+#define DME_STATUS_MEM_COR_ERR BIT(0)
+#define DME_STATUS_MEM_UCOR_ERR BIT(1)
+#define DME_STATUS_FIFO_UNDERFLOW BIT(2)
+#define DME_STATUS_FIFO_OVERFLOW BIT(3)
+#define DME_STATUS_RRESP_ERR BIT(4)
+#define DME_STATUS_BRESP_ERR BIT(5)
+#define DME_STATUS_ERROR_MASK (DME_STATUS_MEM_COR_ERR | \
+ DME_STATUS_MEM_UCOR_ERR | \
+ DME_STATUS_FIFO_UNDERFLOW | \
+ DME_STATUS_FIFO_OVERFLOW | \
+ DME_STATUS_RRESP_ERR | \
+ DME_STATUS_BRESP_ERR)
+
+/* Completion RM status code */
+#define RM_STATUS_CODE_SHIFT 0
+#define RM_STATUS_CODE_MASK 0x3ff
+#define RM_STATUS_CODE_GOOD 0x0
+#define RM_STATUS_CODE_AE_TIMEOUT 0x3ff
+
+/* General descriptor format */
+#define DESC_TYPE_SHIFT 60
+#define DESC_TYPE_MASK 0xf
+#define DESC_PAYLOAD_SHIFT 0
+#define DESC_PAYLOAD_MASK 0x0fffffffffffffff
+
+/* Null descriptor format */
+#define NULL_TYPE 0
+#define NULL_TOGGLE_SHIFT 58
+#define NULL_TOGGLE_MASK 0x1
+
+/* Header descriptor format */
+#define HEADER_TYPE 1
+#define HEADER_TOGGLE_SHIFT 58
+#define HEADER_TOGGLE_MASK 0x1
+#define HEADER_ENDPKT_SHIFT 57
+#define HEADER_ENDPKT_MASK 0x1
+#define HEADER_STARTPKT_SHIFT 56
+#define HEADER_STARTPKT_MASK 0x1
+#define HEADER_BDCOUNT_SHIFT 36
+#define HEADER_BDCOUNT_MASK 0x1f
+#define HEADER_BDCOUNT_MAX HEADER_BDCOUNT_MASK
+#define HEADER_FLAGS_SHIFT 16
+#define HEADER_FLAGS_MASK 0xffff
+#define HEADER_OPAQUE_SHIFT 0
+#define HEADER_OPAQUE_MASK 0xffff
+
+/* Source (SRC) descriptor format */
+#define SRC_TYPE 2
+#define SRC_LENGTH_SHIFT 44
+#define SRC_LENGTH_MASK 0xffff
+#define SRC_ADDR_SHIFT 0
+#define SRC_ADDR_MASK 0x00000fffffffffff
+
+/* Destination (DST) descriptor format */
+#define DST_TYPE 3
+#define DST_LENGTH_SHIFT 44
+#define DST_LENGTH_MASK 0xffff
+#define DST_ADDR_SHIFT 0
+#define DST_ADDR_MASK 0x00000fffffffffff
+
+/* Immediate (IMM) descriptor format */
+#define IMM_TYPE 4
+#define IMM_DATA_SHIFT 0
+#define IMM_DATA_MASK 0x0fffffffffffffff
+
+/* Next pointer (NPTR) descriptor format */
+#define NPTR_TYPE 5
+#define NPTR_TOGGLE_SHIFT 58
+#define NPTR_TOGGLE_MASK 0x1
+#define NPTR_ADDR_SHIFT 0
+#define NPTR_ADDR_MASK 0x00000fffffffffff
+
+/* Mega source (MSRC) descriptor format */
+#define MSRC_TYPE 6
+#define MSRC_LENGTH_SHIFT 44
+#define MSRC_LENGTH_MASK 0xffff
+#define MSRC_ADDR_SHIFT 0
+#define MSRC_ADDR_MASK 0x00000fffffffffff
+
+/* Mega destination (MDST) descriptor format */
+#define MDST_TYPE 7
+#define MDST_LENGTH_SHIFT 44
+#define MDST_LENGTH_MASK 0xffff
+#define MDST_ADDR_SHIFT 0
+#define MDST_ADDR_MASK 0x00000fffffffffff
+
+/* Source with tlast (SRCT) descriptor format */
+#define SRCT_TYPE 8
+#define SRCT_LENGTH_SHIFT 44
+#define SRCT_LENGTH_MASK 0xffff
+#define SRCT_ADDR_SHIFT 0
+#define SRCT_ADDR_MASK 0x00000fffffffffff
+
+/* Destination with tlast (DSTT) descriptor format */
+#define DSTT_TYPE 9
+#define DSTT_LENGTH_SHIFT 44
+#define DSTT_LENGTH_MASK 0xffff
+#define DSTT_ADDR_SHIFT 0
+#define DSTT_ADDR_MASK 0x00000fffffffffff
+
+/* Immediate with tlast (IMMT) descriptor format */
+#define IMMT_TYPE 10
+#define IMMT_DATA_SHIFT 0
+#define IMMT_DATA_MASK 0x0fffffffffffffff
+
+/* Descriptor helper macros */
+#define DESC_DEC(_d, _s, _m) (((_d) >> (_s)) & (_m))
+#define DESC_ENC(_d, _v, _s, _m) \
+ do { \
+ (_d) &= ~((u64)(_m) << (_s)); \
+ (_d) |= (((u64)(_v) & (_m)) << (_s)); \
+ } while (0)
+
+/* ====== FlexRM data structures ===== */
+
+struct flexrm_ring {
+ /* Unprotected members */
+ int num;
+ struct flexrm_mbox *mbox;
+ void __iomem *regs;
+ bool irq_requested;
+ unsigned int irq;
+ unsigned int msi_timer_val;
+ unsigned int msi_count_threshold;
+ struct ida requests_ida;
+ struct brcm_message *requests[RING_MAX_REQ_COUNT];
+ void *bd_base;
+ dma_addr_t bd_dma_base;
+ u32 bd_write_offset;
+ void *cmpl_base;
+ dma_addr_t cmpl_dma_base;
+ /* Protected members */
+ spinlock_t lock;
+ struct brcm_message *last_pending_msg;
+ u32 cmpl_read_offset;
+};
+
+struct flexrm_mbox {
+ struct device *dev;
+ void __iomem *regs;
+ u32 num_rings;
+ struct flexrm_ring *rings;
+ struct dma_pool *bd_pool;
+ struct dma_pool *cmpl_pool;
+ struct mbox_controller controller;
+};
+
+/* ====== FlexRM ring descriptor helper routines ===== */
+
+static u64 flexrm_read_desc(void *desc_ptr)
+{
+ return le64_to_cpu(*((u64 *)desc_ptr));
+}
+
+static void flexrm_write_desc(void *desc_ptr, u64 desc)
+{
+ *((u64 *)desc_ptr) = cpu_to_le64(desc);
+}
+
+static u32 flexrm_cmpl_desc_to_reqid(u64 cmpl_desc)
+{
+ return (u32)(cmpl_desc & CMPL_OPAQUE_MASK);
+}
+
+static int flexrm_cmpl_desc_to_error(u64 cmpl_desc)
+{
+ u32 status;
+
+ status = DESC_DEC(cmpl_desc, CMPL_DME_STATUS_SHIFT,
+ CMPL_DME_STATUS_MASK);
+ if (status & DME_STATUS_ERROR_MASK)
+ return -EIO;
+
+ status = DESC_DEC(cmpl_desc, CMPL_RM_STATUS_SHIFT,
+ CMPL_RM_STATUS_MASK);
+ status &= RM_STATUS_CODE_MASK;
+ if (status == RM_STATUS_CODE_AE_TIMEOUT)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static bool flexrm_is_next_table_desc(void *desc_ptr)
+{
+ u64 desc = flexrm_read_desc(desc_ptr);
+ u32 type = DESC_DEC(desc, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+
+ return (type == NPTR_TYPE) ? true : false;
+}
+
+static u64 flexrm_next_table_desc(u32 toggle, dma_addr_t next_addr)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, NPTR_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, toggle, NPTR_TOGGLE_SHIFT, NPTR_TOGGLE_MASK);
+ DESC_ENC(desc, next_addr, NPTR_ADDR_SHIFT, NPTR_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_null_desc(u32 toggle)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, NULL_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, toggle, NULL_TOGGLE_SHIFT, NULL_TOGGLE_MASK);
+
+ return desc;
+}
+
+static u32 flexrm_estimate_header_desc_count(u32 nhcnt)
+{
+ u32 hcnt = nhcnt / HEADER_BDCOUNT_MAX;
+
+ if (!(nhcnt % HEADER_BDCOUNT_MAX))
+ hcnt += 1;
+
+ return hcnt;
+}
+
+static void flexrm_flip_header_toogle(void *desc_ptr)
+{
+ u64 desc = flexrm_read_desc(desc_ptr);
+
+ if (desc & ((u64)0x1 << HEADER_TOGGLE_SHIFT))
+ desc &= ~((u64)0x1 << HEADER_TOGGLE_SHIFT);
+ else
+ desc |= ((u64)0x1 << HEADER_TOGGLE_SHIFT);
+
+ flexrm_write_desc(desc_ptr, desc);
+}
+
+static u64 flexrm_header_desc(u32 toggle, u32 startpkt, u32 endpkt,
+ u32 bdcount, u32 flags, u32 opaque)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, HEADER_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, toggle, HEADER_TOGGLE_SHIFT, HEADER_TOGGLE_MASK);
+ DESC_ENC(desc, startpkt, HEADER_STARTPKT_SHIFT, HEADER_STARTPKT_MASK);
+ DESC_ENC(desc, endpkt, HEADER_ENDPKT_SHIFT, HEADER_ENDPKT_MASK);
+ DESC_ENC(desc, bdcount, HEADER_BDCOUNT_SHIFT, HEADER_BDCOUNT_MASK);
+ DESC_ENC(desc, flags, HEADER_FLAGS_SHIFT, HEADER_FLAGS_MASK);
+ DESC_ENC(desc, opaque, HEADER_OPAQUE_SHIFT, HEADER_OPAQUE_MASK);
+
+ return desc;
+}
+
+static void flexrm_enqueue_desc(u32 nhpos, u32 nhcnt, u32 reqid,
+ u64 desc, void **desc_ptr, u32 *toggle,
+ void *start_desc, void *end_desc)
+{
+ u64 d;
+ u32 nhavail, _toggle, _startpkt, _endpkt, _bdcount;
+
+ /* Sanity check */
+ if (nhcnt <= nhpos)
+ return;
+
+ /*
+ * Each request or packet start with a HEADER descriptor followed
+ * by one or more non-HEADER descriptors (SRC, SRCT, MSRC, DST,
+ * DSTT, MDST, IMM, and IMMT). The number of non-HEADER descriptors
+ * following a HEADER descriptor is represented by BDCOUNT field
+ * of HEADER descriptor. The max value of BDCOUNT field is 31 which
+ * means we can only have 31 non-HEADER descriptors following one
+ * HEADER descriptor.
+ *
+ * In general use, number of non-HEADER descriptors can easily go
+ * beyond 31. To tackle this situation, we have packet (or request)
+ * extenstion bits (STARTPKT and ENDPKT) in the HEADER descriptor.
+ *
+ * To use packet extension, the first HEADER descriptor of request
+ * (or packet) will have STARTPKT=1 and ENDPKT=0. The intermediate
+ * HEADER descriptors will have STARTPKT=0 and ENDPKT=0. The last
+ * HEADER descriptor will have STARTPKT=0 and ENDPKT=1. Also, the
+ * TOGGLE bit of the first HEADER will be set to invalid state to
+ * ensure that FlexRM does not start fetching descriptors till all
+ * descriptors are enqueued. The user of this function will flip
+ * the TOGGLE bit of first HEADER after all descriptors are
+ * enqueued.
+ */
+
+ if ((nhpos % HEADER_BDCOUNT_MAX == 0) && (nhcnt - nhpos)) {
+ /* Prepare the header descriptor */
+ nhavail = (nhcnt - nhpos);
+ _toggle = (nhpos == 0) ? !(*toggle) : (*toggle);
+ _startpkt = (nhpos == 0) ? 0x1 : 0x0;
+ _endpkt = (nhavail <= HEADER_BDCOUNT_MAX) ? 0x1 : 0x0;
+ _bdcount = (nhavail <= HEADER_BDCOUNT_MAX) ?
+ nhavail : HEADER_BDCOUNT_MAX;
+ if (nhavail <= HEADER_BDCOUNT_MAX)
+ _bdcount = nhavail;
+ else
+ _bdcount = HEADER_BDCOUNT_MAX;
+ d = flexrm_header_desc(_toggle, _startpkt, _endpkt,
+ _bdcount, 0x0, reqid);
+
+ /* Write header descriptor */
+ flexrm_write_desc(*desc_ptr, d);
+
+ /* Point to next descriptor */
+ *desc_ptr += sizeof(desc);
+ if (*desc_ptr == end_desc)
+ *desc_ptr = start_desc;
+
+ /* Skip next pointer descriptors */
+ while (flexrm_is_next_table_desc(*desc_ptr)) {
+ *toggle = (*toggle) ? 0 : 1;
+ *desc_ptr += sizeof(desc);
+ if (*desc_ptr == end_desc)
+ *desc_ptr = start_desc;
+ }
+ }
+
+ /* Write desired descriptor */
+ flexrm_write_desc(*desc_ptr, desc);
+
+ /* Point to next descriptor */
+ *desc_ptr += sizeof(desc);
+ if (*desc_ptr == end_desc)
+ *desc_ptr = start_desc;
+
+ /* Skip next pointer descriptors */
+ while (flexrm_is_next_table_desc(*desc_ptr)) {
+ *toggle = (*toggle) ? 0 : 1;
+ *desc_ptr += sizeof(desc);
+ if (*desc_ptr == end_desc)
+ *desc_ptr = start_desc;
+ }
+}
+
+static u64 flexrm_src_desc(dma_addr_t addr, unsigned int length)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, SRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length, SRC_LENGTH_SHIFT, SRC_LENGTH_MASK);
+ DESC_ENC(desc, addr, SRC_ADDR_SHIFT, SRC_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_msrc_desc(dma_addr_t addr, unsigned int length_div_16)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, MSRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length_div_16, MSRC_LENGTH_SHIFT, MSRC_LENGTH_MASK);
+ DESC_ENC(desc, addr, MSRC_ADDR_SHIFT, MSRC_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_dst_desc(dma_addr_t addr, unsigned int length)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, DST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length, DST_LENGTH_SHIFT, DST_LENGTH_MASK);
+ DESC_ENC(desc, addr, DST_ADDR_SHIFT, DST_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_mdst_desc(dma_addr_t addr, unsigned int length_div_16)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, MDST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length_div_16, MDST_LENGTH_SHIFT, MDST_LENGTH_MASK);
+ DESC_ENC(desc, addr, MDST_ADDR_SHIFT, MDST_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_imm_desc(u64 data)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, IMM_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, data, IMM_DATA_SHIFT, IMM_DATA_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_srct_desc(dma_addr_t addr, unsigned int length)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, SRCT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length, SRCT_LENGTH_SHIFT, SRCT_LENGTH_MASK);
+ DESC_ENC(desc, addr, SRCT_ADDR_SHIFT, SRCT_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_dstt_desc(dma_addr_t addr, unsigned int length)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, DSTT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, length, DSTT_LENGTH_SHIFT, DSTT_LENGTH_MASK);
+ DESC_ENC(desc, addr, DSTT_ADDR_SHIFT, DSTT_ADDR_MASK);
+
+ return desc;
+}
+
+static u64 flexrm_immt_desc(u64 data)
+{
+ u64 desc = 0;
+
+ DESC_ENC(desc, IMMT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
+ DESC_ENC(desc, data, IMMT_DATA_SHIFT, IMMT_DATA_MASK);
+
+ return desc;
+}
+
+static bool flexrm_spu_sanity_check(struct brcm_message *msg)
+{
+ struct scatterlist *sg;
+
+ if (!msg->spu.src || !msg->spu.dst)
+ return false;
+ for (sg = msg->spu.src; sg; sg = sg_next(sg)) {
+ if (sg->length & 0xf) {
+ if (sg->length > SRC_LENGTH_MASK)
+ return false;
+ } else {
+ if (sg->length > (MSRC_LENGTH_MASK * 16))
+ return false;
+ }
+ }
+ for (sg = msg->spu.dst; sg; sg = sg_next(sg)) {
+ if (sg->length & 0xf) {
+ if (sg->length > DST_LENGTH_MASK)
+ return false;
+ } else {
+ if (sg->length > (MDST_LENGTH_MASK * 16))
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static u32 flexrm_spu_estimate_nonheader_desc_count(struct brcm_message *msg)
+{
+ u32 cnt = 0;
+ unsigned int dst_target = 0;
+ struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
+
+ while (src_sg || dst_sg) {
+ if (src_sg) {
+ cnt++;
+ dst_target = src_sg->length;
+ src_sg = sg_next(src_sg);
+ } else
+ dst_target = UINT_MAX;
+
+ while (dst_target && dst_sg) {
+ cnt++;
+ if (dst_sg->length < dst_target)
+ dst_target -= dst_sg->length;
+ else
+ dst_target = 0;
+ dst_sg = sg_next(dst_sg);
+ }
+ }
+
+ return cnt;
+}
+
+static int flexrm_spu_dma_map(struct device *dev, struct brcm_message *msg)
+{
+ int rc;
+
+ rc = dma_map_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
+ DMA_TO_DEVICE);
+ if (rc < 0)
+ return rc;
+
+ rc = dma_map_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
+ DMA_FROM_DEVICE);
+ if (rc < 0) {
+ dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
+ DMA_TO_DEVICE);
+ return rc;
+ }
+
+ return 0;
+}
+
+static void flexrm_spu_dma_unmap(struct device *dev, struct brcm_message *msg)
+{
+ dma_unmap_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
+ DMA_FROM_DEVICE);
+ dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
+ DMA_TO_DEVICE);
+}
+
+static void *flexrm_spu_write_descs(struct brcm_message *msg, u32 nhcnt,
+ u32 reqid, void *desc_ptr, u32 toggle,
+ void *start_desc, void *end_desc)
+{
+ u64 d;
+ u32 nhpos = 0;
+ void *orig_desc_ptr = desc_ptr;
+ unsigned int dst_target = 0;
+ struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
+
+ while (src_sg || dst_sg) {
+ if (src_sg) {
+ if (sg_dma_len(src_sg) & 0xf)
+ d = flexrm_src_desc(sg_dma_address(src_sg),
+ sg_dma_len(src_sg));
+ else
+ d = flexrm_msrc_desc(sg_dma_address(src_sg),
+ sg_dma_len(src_sg)/16);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ dst_target = sg_dma_len(src_sg);
+ src_sg = sg_next(src_sg);
+ } else
+ dst_target = UINT_MAX;
+
+ while (dst_target && dst_sg) {
+ if (sg_dma_len(dst_sg) & 0xf)
+ d = flexrm_dst_desc(sg_dma_address(dst_sg),
+ sg_dma_len(dst_sg));
+ else
+ d = flexrm_mdst_desc(sg_dma_address(dst_sg),
+ sg_dma_len(dst_sg)/16);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ if (sg_dma_len(dst_sg) < dst_target)
+ dst_target -= sg_dma_len(dst_sg);
+ else
+ dst_target = 0;
+ dst_sg = sg_next(dst_sg);
+ }
+ }
+
+ /* Null descriptor with invalid toggle bit */
+ flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
+
+ /* Ensure that descriptors have been written to memory */
+ wmb();
+
+ /* Flip toggle bit in header */
+ flexrm_flip_header_toogle(orig_desc_ptr);
+
+ return desc_ptr;
+}
+
+static bool flexrm_sba_sanity_check(struct brcm_message *msg)
+{
+ u32 i;
+
+ if (!msg->sba.cmds || !msg->sba.cmds_count)
+ return false;
+
+ for (i = 0; i < msg->sba.cmds_count; i++) {
+ if (((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
+ (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C)) &&
+ (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT))
+ return false;
+ if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) &&
+ (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
+ return false;
+ if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C) &&
+ (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
+ return false;
+ if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP) &&
+ (msg->sba.cmds[i].resp_len > DSTT_LENGTH_MASK))
+ return false;
+ if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT) &&
+ (msg->sba.cmds[i].data_len > DSTT_LENGTH_MASK))
+ return false;
+ }
+
+ return true;
+}
+
+static u32 flexrm_sba_estimate_nonheader_desc_count(struct brcm_message *msg)
+{
+ u32 i, cnt;
+
+ cnt = 0;
+ for (i = 0; i < msg->sba.cmds_count; i++) {
+ cnt++;
+
+ if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
+ (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C))
+ cnt++;
+
+ if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP)
+ cnt++;
+
+ if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT)
+ cnt++;
+ }
+
+ return cnt;
+}
+
+static void *flexrm_sba_write_descs(struct brcm_message *msg, u32 nhcnt,
+ u32 reqid, void *desc_ptr, u32 toggle,
+ void *start_desc, void *end_desc)
+{
+ u64 d;
+ u32 i, nhpos = 0;
+ struct brcm_sba_command *c;
+ void *orig_desc_ptr = desc_ptr;
+
+ /* Convert SBA commands into descriptors */
+ for (i = 0; i < msg->sba.cmds_count; i++) {
+ c = &msg->sba.cmds[i];
+
+ if ((c->flags & BRCM_SBA_CMD_HAS_RESP) &&
+ (c->flags & BRCM_SBA_CMD_HAS_OUTPUT)) {
+ /* Destination response descriptor */
+ d = flexrm_dst_desc(c->resp, c->resp_len);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ } else if (c->flags & BRCM_SBA_CMD_HAS_RESP) {
+ /* Destination response with tlast descriptor */
+ d = flexrm_dstt_desc(c->resp, c->resp_len);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ }
+
+ if (c->flags & BRCM_SBA_CMD_HAS_OUTPUT) {
+ /* Destination with tlast descriptor */
+ d = flexrm_dstt_desc(c->data, c->data_len);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ }
+
+ if (c->flags & BRCM_SBA_CMD_TYPE_B) {
+ /* Command as immediate descriptor */
+ d = flexrm_imm_desc(c->cmd);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ } else {
+ /* Command as immediate descriptor with tlast */
+ d = flexrm_immt_desc(c->cmd);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ }
+
+ if ((c->flags & BRCM_SBA_CMD_TYPE_B) ||
+ (c->flags & BRCM_SBA_CMD_TYPE_C)) {
+ /* Source with tlast descriptor */
+ d = flexrm_srct_desc(c->data, c->data_len);
+ flexrm_enqueue_desc(nhpos, nhcnt, reqid,
+ d, &desc_ptr, &toggle,
+ start_desc, end_desc);
+ nhpos++;
+ }
+ }
+
+ /* Null descriptor with invalid toggle bit */
+ flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
+
+ /* Ensure that descriptors have been written to memory */
+ wmb();
+
+ /* Flip toggle bit in header */
+ flexrm_flip_header_toogle(orig_desc_ptr);
+
+ return desc_ptr;
+}
+
+static bool flexrm_sanity_check(struct brcm_message *msg)
+{
+ if (!msg)
+ return false;
+
+ switch (msg->type) {
+ case BRCM_MESSAGE_SPU:
+ return flexrm_spu_sanity_check(msg);
+ case BRCM_MESSAGE_SBA:
+ return flexrm_sba_sanity_check(msg);
+ default:
+ return false;
+ };
+}
+
+static u32 flexrm_estimate_nonheader_desc_count(struct brcm_message *msg)
+{
+ if (!msg)
+ return 0;
+
+ switch (msg->type) {
+ case BRCM_MESSAGE_SPU:
+ return flexrm_spu_estimate_nonheader_desc_count(msg);
+ case BRCM_MESSAGE_SBA:
+ return flexrm_sba_estimate_nonheader_desc_count(msg);
+ default:
+ return 0;
+ };
+}
+
+static int flexrm_dma_map(struct device *dev, struct brcm_message *msg)
+{
+ if (!dev || !msg)
+ return -EINVAL;
+
+ switch (msg->type) {
+ case BRCM_MESSAGE_SPU:
+ return flexrm_spu_dma_map(dev, msg);
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static void flexrm_dma_unmap(struct device *dev, struct brcm_message *msg)
+{
+ if (!dev || !msg)
+ return;
+
+ switch (msg->type) {
+ case BRCM_MESSAGE_SPU:
+ flexrm_spu_dma_unmap(dev, msg);
+ break;
+ default:
+ break;
+ }
+}
+
+static void *flexrm_write_descs(struct brcm_message *msg, u32 nhcnt,
+ u32 reqid, void *desc_ptr, u32 toggle,
+ void *start_desc, void *end_desc)
+{
+ if (!msg || !desc_ptr || !start_desc || !end_desc)
+ return ERR_PTR(-ENOTSUPP);
+
+ if ((desc_ptr < start_desc) || (end_desc <= desc_ptr))
+ return ERR_PTR(-ERANGE);
+
+ switch (msg->type) {
+ case BRCM_MESSAGE_SPU:
+ return flexrm_spu_write_descs(msg, nhcnt, reqid,
+ desc_ptr, toggle,
+ start_desc, end_desc);
+ case BRCM_MESSAGE_SBA:
+ return flexrm_sba_write_descs(msg, nhcnt, reqid,
+ desc_ptr, toggle,
+ start_desc, end_desc);
+ default:
+ return ERR_PTR(-ENOTSUPP);
+ };
+}
+
+/* ====== FlexRM driver helper routines ===== */
+
+static int flexrm_new_request(struct flexrm_ring *ring,
+ struct brcm_message *batch_msg,
+ struct brcm_message *msg)
+{
+ void *next;
+ unsigned long flags;
+ u32 val, count, nhcnt;
+ u32 read_offset, write_offset;
+ bool exit_cleanup = false;
+ int ret = 0, reqid;
+
+ /* Do sanity check on message */
+ if (!flexrm_sanity_check(msg))
+ return -EIO;
+ msg->error = 0;
+
+ /* If no requests possible then save data pointer and goto done. */
+ reqid = ida_simple_get(&ring->requests_ida, 0,
+ RING_MAX_REQ_COUNT, GFP_KERNEL);
+ if (reqid < 0) {
+ spin_lock_irqsave(&ring->lock, flags);
+ if (batch_msg)
+ ring->last_pending_msg = batch_msg;
+ else
+ ring->last_pending_msg = msg;
+ spin_unlock_irqrestore(&ring->lock, flags);
+ return 0;
+ }
+ ring->requests[reqid] = msg;
+
+ /* Do DMA mappings for the message */
+ ret = flexrm_dma_map(ring->mbox->dev, msg);
+ if (ret < 0) {
+ ring->requests[reqid] = NULL;
+ ida_simple_remove(&ring->requests_ida, reqid);
+ return ret;
+ }
+
+ /* If last_pending_msg is already set then goto done with error */
+ spin_lock_irqsave(&ring->lock, flags);
+ if (ring->last_pending_msg)
+ ret = -ENOSPC;
+ spin_unlock_irqrestore(&ring->lock, flags);
+ if (ret < 0) {
+ dev_warn(ring->mbox->dev, "no space in ring %d\n", ring->num);
+ exit_cleanup = true;
+ goto exit;
+ }
+
+ /* Determine current HW BD read offset */
+ read_offset = readl_relaxed(ring->regs + RING_BD_READ_PTR);
+ val = readl_relaxed(ring->regs + RING_BD_START_ADDR);
+ read_offset *= RING_DESC_SIZE;
+ read_offset += (u32)(BD_START_ADDR_DECODE(val) - ring->bd_dma_base);
+
+ /*
+ * Number required descriptors = number of non-header descriptors +
+ * number of header descriptors +
+ * 1x null descriptor
+ */
+ nhcnt = flexrm_estimate_nonheader_desc_count(msg);
+ count = flexrm_estimate_header_desc_count(nhcnt) + nhcnt + 1;
+
+ /* Check for available descriptor space. */
+ write_offset = ring->bd_write_offset;
+ while (count) {
+ if (!flexrm_is_next_table_desc(ring->bd_base + write_offset))
+ count--;
+ write_offset += RING_DESC_SIZE;
+ if (write_offset == RING_BD_SIZE)
+ write_offset = 0x0;
+ if (write_offset == read_offset)
+ break;
+ }
+ if (count) {
+ spin_lock_irqsave(&ring->lock, flags);
+ if (batch_msg)
+ ring->last_pending_msg = batch_msg;
+ else
+ ring->last_pending_msg = msg;
+ spin_unlock_irqrestore(&ring->lock, flags);
+ ret = 0;
+ exit_cleanup = true;
+ goto exit;
+ }
+
+ /* Write descriptors to ring */
+ next = flexrm_write_descs(msg, nhcnt, reqid,
+ ring->bd_base + ring->bd_write_offset,
+ RING_BD_TOGGLE_VALID(ring->bd_write_offset),
+ ring->bd_base, ring->bd_base + RING_BD_SIZE);
+ if (IS_ERR(next)) {
+ ret = PTR_ERR(next);
+ exit_cleanup = true;
+ goto exit;
+ }
+
+ /* Save ring BD write offset */
+ ring->bd_write_offset = (unsigned long)(next - ring->bd_base);
+
+exit:
+ /* Update error status in message */
+ msg->error = ret;
+
+ /* Cleanup if we failed */
+ if (exit_cleanup) {
+ flexrm_dma_unmap(ring->mbox->dev, msg);
+ ring->requests[reqid] = NULL;
+ ida_simple_remove(&ring->requests_ida, reqid);
+ }
+
+ return ret;
+}
+
+static int flexrm_process_completions(struct flexrm_ring *ring)
+{
+ u64 desc;
+ int err, count = 0;
+ unsigned long flags;
+ struct brcm_message *msg = NULL;
+ u32 reqid, cmpl_read_offset, cmpl_write_offset;
+ struct mbox_chan *chan = &ring->mbox->controller.chans[ring->num];
+
+ spin_lock_irqsave(&ring->lock, flags);
+
+ /* Check last_pending_msg */
+ if (ring->last_pending_msg) {
+ msg = ring->last_pending_msg;
+ ring->last_pending_msg = NULL;
+ }
+
+ /*
+ * Get current completion read and write offset
+ *
+ * Note: We should read completion write pointer atleast once
+ * after we get a MSI interrupt because HW maintains internal
+ * MSI status which will allow next MSI interrupt only after
+ * completion write pointer is read.
+ */
+ cmpl_write_offset = readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
+ cmpl_write_offset *= RING_DESC_SIZE;
+ cmpl_read_offset = ring->cmpl_read_offset;
+ ring->cmpl_read_offset = cmpl_write_offset;
+
+ spin_unlock_irqrestore(&ring->lock, flags);
+
+ /* If last_pending_msg was set then queue it back */
+ if (msg)
+ mbox_send_message(chan, msg);
+
+ /* For each completed request notify mailbox clients */
+ reqid = 0;
+ while (cmpl_read_offset != cmpl_write_offset) {
+ /* Dequeue next completion descriptor */
+ desc = *((u64 *)(ring->cmpl_base + cmpl_read_offset));
+
+ /* Next read offset */
+ cmpl_read_offset += RING_DESC_SIZE;
+ if (cmpl_read_offset == RING_CMPL_SIZE)
+ cmpl_read_offset = 0;
+
+ /* Decode error from completion descriptor */
+ err = flexrm_cmpl_desc_to_error(desc);
+ if (err < 0) {
+ dev_warn(ring->mbox->dev,
+ "got completion desc=0x%lx with error %d",
+ (unsigned long)desc, err);
+ }
+
+ /* Determine request id from completion descriptor */
+ reqid = flexrm_cmpl_desc_to_reqid(desc);
+
+ /* Determine message pointer based on reqid */
+ msg = ring->requests[reqid];
+ if (!msg) {
+ dev_warn(ring->mbox->dev,
+ "null msg pointer for completion desc=0x%lx",
+ (unsigned long)desc);
+ continue;
+ }
+
+ /* Release reqid for recycling */
+ ring->requests[reqid] = NULL;
+ ida_simple_remove(&ring->requests_ida, reqid);
+
+ /* Unmap DMA mappings */
+ flexrm_dma_unmap(ring->mbox->dev, msg);
+
+ /* Give-back message to mailbox client */
+ msg->error = err;
+ mbox_chan_received_data(chan, msg);
+
+ /* Increment number of completions processed */
+ count++;
+ }
+
+ return count;
+}
+
+/* ====== FlexRM interrupt handler ===== */
+
+static irqreturn_t flexrm_irq_event(int irq, void *dev_id)
+{
+ /* We only have MSI for completions so just wakeup IRQ thread */
+ /* Ring related errors will be informed via completion descriptors */
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t flexrm_irq_thread(int irq, void *dev_id)
+{
+ flexrm_process_completions(dev_id);
+
+ return IRQ_HANDLED;
+}
+
+/* ====== FlexRM mailbox callbacks ===== */
+
+static int flexrm_send_data(struct mbox_chan *chan, void *data)
+{
+ int i, rc;
+ struct flexrm_ring *ring = chan->con_priv;
+ struct brcm_message *msg = data;
+
+ if (msg->type == BRCM_MESSAGE_BATCH) {
+ for (i = msg->batch.msgs_queued;
+ i < msg->batch.msgs_count; i++) {
+ rc = flexrm_new_request(ring, msg,
+ &msg->batch.msgs[i]);
+ if (rc) {
+ msg->error = rc;
+ return rc;
+ }
+ msg->batch.msgs_queued++;
+ }
+ return 0;
+ }
+
+ return flexrm_new_request(ring, NULL, data);
+}
+
+static bool flexrm_peek_data(struct mbox_chan *chan)
+{
+ int cnt = flexrm_process_completions(chan->con_priv);
+
+ return (cnt > 0) ? true : false;
+}
+
+static int flexrm_startup(struct mbox_chan *chan)
+{
+ u64 d;
+ u32 val, off;
+ int ret = 0;
+ dma_addr_t next_addr;
+ struct flexrm_ring *ring = chan->con_priv;
+
+ /* Allocate BD memory */
+ ring->bd_base = dma_pool_alloc(ring->mbox->bd_pool,
+ GFP_KERNEL, &ring->bd_dma_base);
+ if (!ring->bd_base) {
+ dev_err(ring->mbox->dev, "can't allocate BD memory\n");
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ /* Configure next table pointer entries in BD memory */
+ for (off = 0; off < RING_BD_SIZE; off += RING_DESC_SIZE) {
+ next_addr = off + RING_DESC_SIZE;
+ if (next_addr == RING_BD_SIZE)
+ next_addr = 0;
+ next_addr += ring->bd_dma_base;
+ if (RING_BD_ALIGN_CHECK(next_addr))
+ d = flexrm_next_table_desc(RING_BD_TOGGLE_VALID(off),
+ next_addr);
+ else
+ d = flexrm_null_desc(RING_BD_TOGGLE_INVALID(off));
+ flexrm_write_desc(ring->bd_base + off, d);
+ }
+
+ /* Allocate completion memory */
+ ring->cmpl_base = dma_pool_alloc(ring->mbox->cmpl_pool,
+ GFP_KERNEL, &ring->cmpl_dma_base);
+ if (!ring->cmpl_base) {
+ dev_err(ring->mbox->dev, "can't allocate completion memory\n");
+ ret = -ENOMEM;
+ goto fail_free_bd_memory;
+ }
+ memset(ring->cmpl_base, 0, RING_CMPL_SIZE);
+
+ /* Request IRQ */
+ if (ring->irq == UINT_MAX) {
+ dev_err(ring->mbox->dev, "ring IRQ not available\n");
+ ret = -ENODEV;
+ goto fail_free_cmpl_memory;
+ }
+ ret = request_threaded_irq(ring->irq,
+ flexrm_irq_event,
+ flexrm_irq_thread,
+ 0, dev_name(ring->mbox->dev), ring);
+ if (ret) {
+ dev_err(ring->mbox->dev, "failed to request ring IRQ\n");
+ goto fail_free_cmpl_memory;
+ }
+ ring->irq_requested = true;
+
+ /* Disable/inactivate ring */
+ writel_relaxed(0x0, ring->regs + RING_CONTROL);
+
+ /* Program BD start address */
+ val = BD_START_ADDR_VALUE(ring->bd_dma_base);
+ writel_relaxed(val, ring->regs + RING_BD_START_ADDR);
+
+ /* BD write pointer will be same as HW write pointer */
+ ring->bd_write_offset =
+ readl_relaxed(ring->regs + RING_BD_WRITE_PTR);
+ ring->bd_write_offset *= RING_DESC_SIZE;
+
+ /* Program completion start address */
+ val = CMPL_START_ADDR_VALUE(ring->cmpl_dma_base);
+ writel_relaxed(val, ring->regs + RING_CMPL_START_ADDR);
+
+ /* Ensure last pending message is cleared */
+ ring->last_pending_msg = NULL;
+
+ /* Completion read pointer will be same as HW write pointer */
+ ring->cmpl_read_offset =
+ readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
+ ring->cmpl_read_offset *= RING_DESC_SIZE;
+
+ /* Read ring Tx, Rx, and Outstanding counts to clear */
+ readl_relaxed(ring->regs + RING_NUM_REQ_RECV_LS);
+ readl_relaxed(ring->regs + RING_NUM_REQ_RECV_MS);
+ readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_LS);
+ readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_MS);
+ readl_relaxed(ring->regs + RING_NUM_REQ_OUTSTAND);
+
+ /* Configure RING_MSI_CONTROL */
+ val = 0;
+ val |= (ring->msi_timer_val << MSI_TIMER_VAL_SHIFT);
+ val |= BIT(MSI_ENABLE_SHIFT);
+ val |= (ring->msi_count_threshold & MSI_COUNT_MASK) << MSI_COUNT_SHIFT;
+ writel_relaxed(val, ring->regs + RING_MSI_CONTROL);
+
+ /* Enable/activate ring */
+ val = BIT(CONTROL_ACTIVE_SHIFT);
+ writel_relaxed(val, ring->regs + RING_CONTROL);
+
+ return 0;
+
+fail_free_cmpl_memory:
+ dma_pool_free(ring->mbox->cmpl_pool,
+ ring->cmpl_base, ring->cmpl_dma_base);
+ ring->cmpl_base = NULL;
+fail_free_bd_memory:
+ dma_pool_free(ring->mbox->bd_pool,
+ ring->bd_base, ring->bd_dma_base);
+ ring->bd_base = NULL;
+fail:
+ return ret;
+}
+
+static void flexrm_shutdown(struct mbox_chan *chan)
+{
+ u32 reqid;
+ unsigned int timeout;
+ struct brcm_message *msg;
+ struct flexrm_ring *ring = chan->con_priv;
+
+ /* Disable/inactivate ring */
+ writel_relaxed(0x0, ring->regs + RING_CONTROL);
+
+ /* Flush ring with timeout of 1s */
+ timeout = 1000;
+ writel_relaxed(BIT(CONTROL_FLUSH_SHIFT),
+ ring->regs + RING_CONTROL);
+ do {
+ if (readl_relaxed(ring->regs + RING_FLUSH_DONE) &
+ FLUSH_DONE_MASK)
+ break;
+ mdelay(1);
+ } while (timeout--);
+
+ /* Abort all in-flight requests */
+ for (reqid = 0; reqid < RING_MAX_REQ_COUNT; reqid++) {
+ msg = ring->requests[reqid];
+ if (!msg)
+ continue;
+
+ /* Release reqid for recycling */
+ ring->requests[reqid] = NULL;
+ ida_simple_remove(&ring->requests_ida, reqid);
+
+ /* Unmap DMA mappings */
+ flexrm_dma_unmap(ring->mbox->dev, msg);
+
+ /* Give-back message to mailbox client */
+ msg->error = -EIO;
+ mbox_chan_received_data(chan, msg);
+ }
+
+ /* Release IRQ */
+ if (ring->irq_requested) {
+ free_irq(ring->irq, ring);
+ ring->irq_requested = false;
+ }
+
+ /* Free-up completion descriptor ring */
+ if (ring->cmpl_base) {
+ dma_pool_free(ring->mbox->cmpl_pool,
+ ring->cmpl_base, ring->cmpl_dma_base);
+ ring->cmpl_base = NULL;
+ }
+
+ /* Free-up BD descriptor ring */
+ if (ring->bd_base) {
+ dma_pool_free(ring->mbox->bd_pool,
+ ring->bd_base, ring->bd_dma_base);
+ ring->bd_base = NULL;
+ }
+}
+
+static bool flexrm_last_tx_done(struct mbox_chan *chan)
+{
+ bool ret;
+ unsigned long flags;
+ struct flexrm_ring *ring = chan->con_priv;
+
+ spin_lock_irqsave(&ring->lock, flags);
+ ret = (ring->last_pending_msg) ? false : true;
+ spin_unlock_irqrestore(&ring->lock, flags);
+
+ return ret;
+}
+
+static const struct mbox_chan_ops flexrm_mbox_chan_ops = {
+ .send_data = flexrm_send_data,
+ .startup = flexrm_startup,
+ .shutdown = flexrm_shutdown,
+ .last_tx_done = flexrm_last_tx_done,
+ .peek_data = flexrm_peek_data,
+};
+
+static struct mbox_chan *flexrm_mbox_of_xlate(struct mbox_controller *cntlr,
+ const struct of_phandle_args *pa)
+{
+ struct mbox_chan *chan;
+ struct flexrm_ring *ring;
+
+ if (pa->args_count < 3)
+ return ERR_PTR(-EINVAL);
+
+ if (pa->args[0] >= cntlr->num_chans)
+ return ERR_PTR(-ENOENT);
+
+ if (pa->args[1] > MSI_COUNT_MASK)
+ return ERR_PTR(-EINVAL);
+
+ if (pa->args[2] > MSI_TIMER_VAL_MASK)
+ return ERR_PTR(-EINVAL);
+
+ chan = &cntlr->chans[pa->args[0]];
+ ring = chan->con_priv;
+ ring->msi_count_threshold = pa->args[1];
+ ring->msi_timer_val = pa->args[2];
+
+ return chan;
+}
+
+/* ====== FlexRM platform driver ===== */
+
+static void flexrm_mbox_msi_write(struct msi_desc *desc, struct msi_msg *msg)
+{
+ struct device *dev = msi_desc_to_dev(desc);
+ struct flexrm_mbox *mbox = dev_get_drvdata(dev);
+ struct flexrm_ring *ring = &mbox->rings[desc->platform.msi_index];
+
+ /* Configure per-Ring MSI registers */
+ writel_relaxed(msg->address_lo, ring->regs + RING_MSI_ADDR_LS);
+ writel_relaxed(msg->address_hi, ring->regs + RING_MSI_ADDR_MS);
+ writel_relaxed(msg->data, ring->regs + RING_MSI_DATA_VALUE);
+}
+
+static int flexrm_mbox_probe(struct platform_device *pdev)
+{
+ int index, ret = 0;
+ void __iomem *regs;
+ void __iomem *regs_end;
+ struct msi_desc *desc;
+ struct resource *iomem;
+ struct flexrm_ring *ring;
+ struct flexrm_mbox *mbox;
+ struct device *dev = &pdev->dev;
+
+ /* Allocate driver mailbox struct */
+ mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
+ if (!mbox) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ mbox->dev = dev;
+ platform_set_drvdata(pdev, mbox);
+
+ /* Get resource for registers */
+ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!iomem || (resource_size(iomem) < RING_REGS_SIZE)) {
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ /* Map registers of all rings */
+ mbox->regs = devm_ioremap_resource(&pdev->dev, iomem);
+ if (IS_ERR(mbox->regs)) {
+ ret = PTR_ERR(mbox->regs);
+ dev_err(&pdev->dev, "Failed to remap mailbox regs: %d\n", ret);
+ goto fail;
+ }
+ regs_end = mbox->regs + resource_size(iomem);
+
+ /* Scan and count available rings */
+ mbox->num_rings = 0;
+ for (regs = mbox->regs; regs < regs_end; regs += RING_REGS_SIZE) {
+ if (readl_relaxed(regs + RING_VER) == RING_VER_MAGIC)
+ mbox->num_rings++;
+ }
+ if (!mbox->num_rings) {
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ /* Allocate driver ring structs */
+ ring = devm_kcalloc(dev, mbox->num_rings, sizeof(*ring), GFP_KERNEL);
+ if (!ring) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ mbox->rings = ring;
+
+ /* Initialize members of driver ring structs */
+ regs = mbox->regs;
+ for (index = 0; index < mbox->num_rings; index++) {
+ ring = &mbox->rings[index];
+ ring->num = index;
+ ring->mbox = mbox;
+ while ((regs < regs_end) &&
+ (readl_relaxed(regs + RING_VER) != RING_VER_MAGIC))
+ regs += RING_REGS_SIZE;
+ if (regs_end <= regs) {
+ ret = -ENODEV;
+ goto fail;
+ }
+ ring->regs = regs;
+ regs += RING_REGS_SIZE;
+ ring->irq = UINT_MAX;
+ ring->irq_requested = false;
+ ring->msi_timer_val = MSI_TIMER_VAL_MASK;
+ ring->msi_count_threshold = 0x1;
+ ida_init(&ring->requests_ida);
+ memset(ring->requests, 0, sizeof(ring->requests));
+ ring->bd_base = NULL;
+ ring->bd_dma_base = 0;
+ ring->cmpl_base = NULL;
+ ring->cmpl_dma_base = 0;
+ spin_lock_init(&ring->lock);
+ ring->last_pending_msg = NULL;
+ ring->cmpl_read_offset = 0;
+ }
+
+ /* FlexRM is capable of 40-bit physical addresses only */
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(40));
+ if (ret) {
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+ if (ret)
+ goto fail;
+ }
+
+ /* Create DMA pool for ring BD memory */
+ mbox->bd_pool = dma_pool_create("bd", dev, RING_BD_SIZE,
+ 1 << RING_BD_ALIGN_ORDER, 0);
+ if (!mbox->bd_pool) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ /* Create DMA pool for ring completion memory */
+ mbox->cmpl_pool = dma_pool_create("cmpl", dev, RING_CMPL_SIZE,
+ 1 << RING_CMPL_ALIGN_ORDER, 0);
+ if (!mbox->cmpl_pool) {
+ ret = -ENOMEM;
+ goto fail_destroy_bd_pool;
+ }
+
+ /* Allocate platform MSIs for each ring */
+ ret = platform_msi_domain_alloc_irqs(dev, mbox->num_rings,
+ flexrm_mbox_msi_write);
+ if (ret)
+ goto fail_destroy_cmpl_pool;
+
+ /* Save alloced IRQ numbers for each ring */
+ for_each_msi_entry(desc, dev) {
+ ring = &mbox->rings[desc->platform.msi_index];
+ ring->irq = desc->irq;
+ }
+
+ /* Initialize mailbox controller */
+ mbox->controller.txdone_irq = false;
+ mbox->controller.txdone_poll = true;
+ mbox->controller.txpoll_period = 1;
+ mbox->controller.ops = &flexrm_mbox_chan_ops;
+ mbox->controller.dev = dev;
+ mbox->controller.num_chans = mbox->num_rings;
+ mbox->controller.of_xlate = flexrm_mbox_of_xlate;
+ mbox->controller.chans = devm_kcalloc(dev, mbox->num_rings,
+ sizeof(*mbox->controller.chans), GFP_KERNEL);
+ if (!mbox->controller.chans) {
+ ret = -ENOMEM;
+ goto fail_free_msis;
+ }
+ for (index = 0; index < mbox->num_rings; index++)
+ mbox->controller.chans[index].con_priv = &mbox->rings[index];
+
+ /* Register mailbox controller */
+ ret = mbox_controller_register(&mbox->controller);
+ if (ret)
+ goto fail_free_msis;
+
+ dev_info(dev, "registered flexrm mailbox with %d channels\n",
+ mbox->controller.num_chans);
+
+ return 0;
+
+fail_free_msis:
+ platform_msi_domain_free_irqs(dev);
+fail_destroy_cmpl_pool:
+ dma_pool_destroy(mbox->cmpl_pool);
+fail_destroy_bd_pool:
+ dma_pool_destroy(mbox->bd_pool);
+fail:
+ return ret;
+}
+
+static int flexrm_mbox_remove(struct platform_device *pdev)
+{
+ int index;
+ struct device *dev = &pdev->dev;
+ struct flexrm_ring *ring;
+ struct flexrm_mbox *mbox = platform_get_drvdata(pdev);
+
+ mbox_controller_unregister(&mbox->controller);
+
+ platform_msi_domain_free_irqs(dev);
+
+ dma_pool_destroy(mbox->cmpl_pool);
+ dma_pool_destroy(mbox->bd_pool);
+
+ for (index = 0; index < mbox->num_rings; index++) {
+ ring = &mbox->rings[index];
+ ida_destroy(&ring->requests_ida);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id flexrm_mbox_of_match[] = {
+ { .compatible = "brcm,iproc-flexrm-mbox", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, flexrm_mbox_of_match);
+
+static struct platform_driver flexrm_mbox_driver = {
+ .driver = {
+ .name = "brcm-flexrm-mbox",
+ .of_match_table = flexrm_mbox_of_match,
+ },
+ .probe = flexrm_mbox_probe,
+ .remove = flexrm_mbox_remove,
+};
+module_platform_driver(flexrm_mbox_driver);
+
+MODULE_AUTHOR("Anup Patel <anup.patel@broadcom.com>");
+MODULE_DESCRIPTION("Broadcom FlexRM mailbox driver");
+MODULE_LICENSE("GPL v2");
projects / platform / kernel / linux-rpi.git / commitdiff