soundwire: cdns: Add cadence library
authorVinod Koul <vinod.koul@intel.com>
Thu, 14 Dec 2017 05:49:41 +0000 (11:19 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 19 Dec 2017 10:31:00 +0000 (11:31 +0100)
Cadence IP implements SoundWire Master. Add base cadence library
initialization and interrupt handling

Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/soundwire/Kconfig
drivers/soundwire/Makefile
drivers/soundwire/cadence_master.c [new file with mode: 0644]
drivers/soundwire/cadence_master.h [new file with mode: 0644]

index d7d3908..534e255 100644 (file)
@@ -19,4 +19,7 @@ comment "SoundWire Devices"
 config SOUNDWIRE_BUS
        tristate
 
+config SOUNDWIRE_CADENCE
+       tristate
+
 endif
index bcde0d2..1e8e966 100644 (file)
@@ -5,3 +5,7 @@
 #Bus Objs
 soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o
 obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o
+
+#Cadence Objs
+soundwire-cadence-objs := cadence_master.o
+obj-$(CONFIG_SOUNDWIRE_CADENCE) += soundwire-cadence.o
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
new file mode 100644 (file)
index 0000000..afaeb9d
--- /dev/null
@@ -0,0 +1,431 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+/*
+ * Cadence SoundWire Master module
+ * Used by Master driver
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/soundwire/sdw_registers.h>
+#include <linux/soundwire/sdw.h>
+#include "bus.h"
+#include "cadence_master.h"
+
+#define CDNS_MCP_CONFIG                                0x0
+
+#define CDNS_MCP_CONFIG_MCMD_RETRY             GENMASK(27, 24)
+#define CDNS_MCP_CONFIG_MPREQ_DELAY            GENMASK(20, 16)
+#define CDNS_MCP_CONFIG_MMASTER                        BIT(7)
+#define CDNS_MCP_CONFIG_BUS_REL                        BIT(6)
+#define CDNS_MCP_CONFIG_SNIFFER                        BIT(5)
+#define CDNS_MCP_CONFIG_SSPMOD                 BIT(4)
+#define CDNS_MCP_CONFIG_CMD                    BIT(3)
+#define CDNS_MCP_CONFIG_OP                     GENMASK(2, 0)
+#define CDNS_MCP_CONFIG_OP_NORMAL              0
+
+#define CDNS_MCP_CONTROL                       0x4
+
+#define CDNS_MCP_CONTROL_RST_DELAY             GENMASK(10, 8)
+#define CDNS_MCP_CONTROL_CMD_RST               BIT(7)
+#define CDNS_MCP_CONTROL_SOFT_RST              BIT(6)
+#define CDNS_MCP_CONTROL_SW_RST                        BIT(5)
+#define CDNS_MCP_CONTROL_HW_RST                        BIT(4)
+#define CDNS_MCP_CONTROL_CLK_PAUSE             BIT(3)
+#define CDNS_MCP_CONTROL_CLK_STOP_CLR          BIT(2)
+#define CDNS_MCP_CONTROL_CMD_ACCEPT            BIT(1)
+#define CDNS_MCP_CONTROL_BLOCK_WAKEUP          BIT(0)
+
+
+#define CDNS_MCP_CMDCTRL                       0x8
+#define CDNS_MCP_SSPSTAT                       0xC
+#define CDNS_MCP_FRAME_SHAPE                   0x10
+#define CDNS_MCP_FRAME_SHAPE_INIT              0x14
+
+#define CDNS_MCP_CONFIG_UPDATE                 0x18
+#define CDNS_MCP_CONFIG_UPDATE_BIT             BIT(0)
+
+#define CDNS_MCP_PHYCTRL                       0x1C
+#define CDNS_MCP_SSP_CTRL0                     0x20
+#define CDNS_MCP_SSP_CTRL1                     0x28
+#define CDNS_MCP_CLK_CTRL0                     0x30
+#define CDNS_MCP_CLK_CTRL1                     0x38
+
+#define CDNS_MCP_STAT                          0x40
+
+#define CDNS_MCP_STAT_ACTIVE_BANK              BIT(20)
+#define CDNS_MCP_STAT_CLK_STOP                 BIT(16)
+
+#define CDNS_MCP_INTSTAT                       0x44
+#define CDNS_MCP_INTMASK                       0x48
+
+#define CDNS_MCP_INT_IRQ                       BIT(31)
+#define CDNS_MCP_INT_WAKEUP                    BIT(16)
+#define CDNS_MCP_INT_SLAVE_RSVD                        BIT(15)
+#define CDNS_MCP_INT_SLAVE_ALERT               BIT(14)
+#define CDNS_MCP_INT_SLAVE_ATTACH              BIT(13)
+#define CDNS_MCP_INT_SLAVE_NATTACH             BIT(12)
+#define CDNS_MCP_INT_SLAVE_MASK                        GENMASK(15, 12)
+#define CDNS_MCP_INT_DPINT                     BIT(11)
+#define CDNS_MCP_INT_CTRL_CLASH                        BIT(10)
+#define CDNS_MCP_INT_DATA_CLASH                        BIT(9)
+#define CDNS_MCP_INT_CMD_ERR                   BIT(7)
+#define CDNS_MCP_INT_RX_WL                     BIT(2)
+#define CDNS_MCP_INT_TXE                       BIT(1)
+
+#define CDNS_MCP_INTSET                                0x4C
+
+#define CDNS_SDW_SLAVE_STAT                    0x50
+#define CDNS_MCP_SLAVE_STAT_MASK               BIT(1, 0)
+
+#define CDNS_MCP_SLAVE_INTSTAT0                        0x54
+#define CDNS_MCP_SLAVE_INTSTAT1                        0x58
+#define CDNS_MCP_SLAVE_INTSTAT_NPRESENT                BIT(0)
+#define CDNS_MCP_SLAVE_INTSTAT_ATTACHED                BIT(1)
+#define CDNS_MCP_SLAVE_INTSTAT_ALERT           BIT(2)
+#define CDNS_MCP_SLAVE_INTSTAT_RESERVED                BIT(3)
+#define CDNS_MCP_SLAVE_STATUS_BITS             GENMASK(3, 0)
+#define CDNS_MCP_SLAVE_STATUS_NUM              4
+
+#define CDNS_MCP_SLAVE_INTMASK0                        0x5C
+#define CDNS_MCP_SLAVE_INTMASK1                        0x60
+
+#define CDNS_MCP_SLAVE_INTMASK0_MASK           GENMASK(30, 0)
+#define CDNS_MCP_SLAVE_INTMASK1_MASK           GENMASK(16, 0)
+
+#define CDNS_MCP_PORT_INTSTAT                  0x64
+#define CDNS_MCP_PDI_STAT                      0x6C
+
+#define CDNS_MCP_FIFOLEVEL                     0x78
+#define CDNS_MCP_FIFOSTAT                      0x7C
+#define CDNS_MCP_RX_FIFO_AVAIL                 GENMASK(5, 0)
+
+#define CDNS_MCP_CMD_BASE                      0x80
+#define CDNS_MCP_RESP_BASE                     0x80
+#define CDNS_MCP_CMD_LEN                       0x20
+#define CDNS_MCP_CMD_WORD_LEN                  0x4
+
+#define CDNS_MCP_CMD_SSP_TAG                   BIT(31)
+#define CDNS_MCP_CMD_COMMAND                   GENMASK(30, 28)
+#define CDNS_MCP_CMD_DEV_ADDR                  GENMASK(27, 24)
+#define CDNS_MCP_CMD_REG_ADDR_H                        GENMASK(23, 16)
+#define CDNS_MCP_CMD_REG_ADDR_L                        GENMASK(15, 8)
+#define CDNS_MCP_CMD_REG_DATA                  GENMASK(7, 0)
+
+#define CDNS_MCP_CMD_READ                      2
+#define CDNS_MCP_CMD_WRITE                     3
+
+#define CDNS_MCP_RESP_RDATA                    GENMASK(15, 8)
+#define CDNS_MCP_RESP_ACK                      BIT(0)
+#define CDNS_MCP_RESP_NACK                     BIT(1)
+
+#define CDNS_DP_SIZE                           128
+
+#define CDNS_DPN_B0_CONFIG(n)                  (0x100 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B0_CH_EN(n)                   (0x104 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B0_SAMPLE_CTRL(n)             (0x108 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B0_OFFSET_CTRL(n)             (0x10C + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B0_HCTRL(n)                   (0x110 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B0_ASYNC_CTRL(n)              (0x114 + CDNS_DP_SIZE * (n))
+
+#define CDNS_DPN_B1_CONFIG(n)                  (0x118 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B1_CH_EN(n)                   (0x11C + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B1_SAMPLE_CTRL(n)             (0x120 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B1_OFFSET_CTRL(n)             (0x124 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B1_HCTRL(n)                   (0x128 + CDNS_DP_SIZE * (n))
+#define CDNS_DPN_B1_ASYNC_CTRL(n)              (0x12C + CDNS_DP_SIZE * (n))
+
+#define CDNS_DPN_CONFIG_BPM                    BIT(18)
+#define CDNS_DPN_CONFIG_BGC                    GENMASK(17, 16)
+#define CDNS_DPN_CONFIG_WL                     GENMASK(12, 8)
+#define CDNS_DPN_CONFIG_PORT_DAT               GENMASK(3, 2)
+#define CDNS_DPN_CONFIG_PORT_FLOW              GENMASK(1, 0)
+
+#define CDNS_DPN_SAMPLE_CTRL_SI                        GENMASK(15, 0)
+
+#define CDNS_DPN_OFFSET_CTRL_1                 GENMASK(7, 0)
+#define CDNS_DPN_OFFSET_CTRL_2                 GENMASK(15, 8)
+
+#define CDNS_DPN_HCTRL_HSTOP                   GENMASK(3, 0)
+#define CDNS_DPN_HCTRL_HSTART                  GENMASK(7, 4)
+#define CDNS_DPN_HCTRL_LCTRL                   GENMASK(10, 8)
+
+#define CDNS_PORTCTRL                          0x130
+#define CDNS_PORTCTRL_DIRN                     BIT(7)
+#define CDNS_PORTCTRL_BANK_INVERT              BIT(8)
+
+#define CDNS_PORT_OFFSET                       0x80
+
+#define CDNS_PDI_CONFIG(n)                     (0x1100 + (n) * 16)
+
+#define CDNS_PDI_CONFIG_SOFT_RESET             BIT(24)
+#define CDNS_PDI_CONFIG_CHANNEL                        GENMASK(15, 8)
+#define CDNS_PDI_CONFIG_PORT                   GENMASK(4, 0)
+
+/* Driver defaults */
+
+#define CDNS_DEFAULT_CLK_DIVIDER               0
+#define CDNS_DEFAULT_FRAME_SHAPE               0x30
+#define CDNS_DEFAULT_SSP_INTERVAL              0x18
+#define CDNS_TX_TIMEOUT                                2000
+
+#define CDNS_PCM_PDI_OFFSET                    0x2
+#define CDNS_PDM_PDI_OFFSET                    0x6
+
+#define CDNS_SCP_RX_FIFOLEVEL                  0x2
+
+/*
+ * register accessor helpers
+ */
+static inline u32 cdns_readl(struct sdw_cdns *cdns, int offset)
+{
+       return readl(cdns->registers + offset);
+}
+
+static inline void cdns_writel(struct sdw_cdns *cdns, int offset, u32 value)
+{
+       writel(value, cdns->registers + offset);
+}
+
+static inline void cdns_updatel(struct sdw_cdns *cdns,
+                               int offset, u32 mask, u32 val)
+{
+       u32 tmp;
+
+       tmp = cdns_readl(cdns, offset);
+       tmp = (tmp & ~mask) | val;
+       cdns_writel(cdns, offset, tmp);
+}
+
+static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value)
+{
+       int timeout = 10;
+       u32 reg_read;
+
+       writel(value, cdns->registers + offset);
+
+       /* Wait for bit to be self cleared */
+       do {
+               reg_read = readl(cdns->registers + offset);
+               if ((reg_read & value) == 0)
+                       return 0;
+
+               timeout--;
+               udelay(50);
+       } while (timeout != 0);
+
+       return -EAGAIN;
+}
+
+/*
+ * IRQ handling
+ */
+
+static int cdns_update_slave_status(struct sdw_cdns *cdns,
+                                       u32 slave0, u32 slave1)
+{
+       enum sdw_slave_status status[SDW_MAX_DEVICES + 1];
+       bool is_slave = false;
+       u64 slave, mask;
+       int i, set_status;
+
+       /* combine the two status */
+       slave = ((u64)slave1 << 32) | slave0;
+       memset(status, 0, sizeof(status));
+
+       for (i = 0; i <= SDW_MAX_DEVICES; i++) {
+               mask = (slave >> (i * CDNS_MCP_SLAVE_STATUS_NUM)) &
+                               CDNS_MCP_SLAVE_STATUS_BITS;
+               if (!mask)
+                       continue;
+
+               is_slave = true;
+               set_status = 0;
+
+               if (mask & CDNS_MCP_SLAVE_INTSTAT_RESERVED) {
+                       status[i] = SDW_SLAVE_RESERVED;
+                       set_status++;
+               }
+
+               if (mask & CDNS_MCP_SLAVE_INTSTAT_ATTACHED) {
+                       status[i] = SDW_SLAVE_ATTACHED;
+                       set_status++;
+               }
+
+               if (mask & CDNS_MCP_SLAVE_INTSTAT_ALERT) {
+                       status[i] = SDW_SLAVE_ALERT;
+                       set_status++;
+               }
+
+               if (mask & CDNS_MCP_SLAVE_INTSTAT_NPRESENT) {
+                       status[i] = SDW_SLAVE_UNATTACHED;
+                       set_status++;
+               }
+
+               /* first check if Slave reported multiple status */
+               if (set_status > 1) {
+                       dev_warn(cdns->dev,
+                                       "Slave reported multiple Status: %d\n",
+                                       status[i]);
+                       /*
+                        * TODO: we need to reread the status here by
+                        * issuing a PING cmd
+                        */
+               }
+       }
+
+       if (is_slave)
+               return sdw_handle_slave_status(&cdns->bus, status);
+
+       return 0;
+}
+
+/**
+ * sdw_cdns_irq() - Cadence interrupt handler
+ * @irq: irq number
+ * @dev_id: irq context
+ */
+irqreturn_t sdw_cdns_irq(int irq, void *dev_id)
+{
+       struct sdw_cdns *cdns = dev_id;
+       u32 int_status;
+       int ret = IRQ_HANDLED;
+
+       /* Check if the link is up */
+       if (!cdns->link_up)
+               return IRQ_NONE;
+
+       int_status = cdns_readl(cdns, CDNS_MCP_INTSTAT);
+
+       if (!(int_status & CDNS_MCP_INT_IRQ))
+               return IRQ_NONE;
+
+       if (int_status & CDNS_MCP_INT_CTRL_CLASH) {
+
+               /* Slave is driving bit slot during control word */
+               dev_err_ratelimited(cdns->dev, "Bus clash for control word\n");
+               int_status |= CDNS_MCP_INT_CTRL_CLASH;
+       }
+
+       if (int_status & CDNS_MCP_INT_DATA_CLASH) {
+               /*
+                * Multiple slaves trying to drive bit slot, or issue with
+                * ownership of data bits or Slave gone bonkers
+                */
+               dev_err_ratelimited(cdns->dev, "Bus clash for data word\n");
+               int_status |= CDNS_MCP_INT_DATA_CLASH;
+       }
+
+       if (int_status & CDNS_MCP_INT_SLAVE_MASK) {
+               /* Mask the Slave interrupt and wake thread */
+               cdns_updatel(cdns, CDNS_MCP_INTMASK,
+                               CDNS_MCP_INT_SLAVE_MASK, 0);
+
+               int_status &= ~CDNS_MCP_INT_SLAVE_MASK;
+               ret = IRQ_WAKE_THREAD;
+       }
+
+       cdns_writel(cdns, CDNS_MCP_INTSTAT, int_status);
+       return ret;
+}
+EXPORT_SYMBOL(sdw_cdns_irq);
+
+/**
+ * sdw_cdns_thread() - Cadence irq thread handler
+ * @irq: irq number
+ * @dev_id: irq context
+ */
+irqreturn_t sdw_cdns_thread(int irq, void *dev_id)
+{
+       struct sdw_cdns *cdns = dev_id;
+       u32 slave0, slave1;
+
+       dev_dbg(cdns->dev, "Slave status change\n");
+
+       slave0 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT0);
+       slave1 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT1);
+
+       cdns_update_slave_status(cdns, slave0, slave1);
+       cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT0, slave0);
+       cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT1, slave1);
+
+       /* clear and unmask Slave interrupt now */
+       cdns_writel(cdns, CDNS_MCP_INTSTAT, CDNS_MCP_INT_SLAVE_MASK);
+       cdns_updatel(cdns, CDNS_MCP_INTMASK,
+                       CDNS_MCP_INT_SLAVE_MASK, CDNS_MCP_INT_SLAVE_MASK);
+
+       return IRQ_HANDLED;
+}
+EXPORT_SYMBOL(sdw_cdns_thread);
+
+/*
+ * init routines
+ */
+
+/**
+ * sdw_cdns_init() - Cadence initialization
+ * @cdns: Cadence instance
+ */
+int sdw_cdns_init(struct sdw_cdns *cdns)
+{
+       u32 val;
+       int ret;
+
+       /* Exit clock stop */
+       ret = cdns_clear_bit(cdns, CDNS_MCP_CONTROL,
+                       CDNS_MCP_CONTROL_CLK_STOP_CLR);
+       if (ret < 0) {
+               dev_err(cdns->dev, "Couldn't exit from clock stop\n");
+               return ret;
+       }
+
+       /* Set clock divider */
+       val = cdns_readl(cdns, CDNS_MCP_CLK_CTRL0);
+       val |= CDNS_DEFAULT_CLK_DIVIDER;
+       cdns_writel(cdns, CDNS_MCP_CLK_CTRL0, val);
+
+       /* Set the default frame shape */
+       cdns_writel(cdns, CDNS_MCP_FRAME_SHAPE_INIT, CDNS_DEFAULT_FRAME_SHAPE);
+
+       /* Set SSP interval to default value */
+       cdns_writel(cdns, CDNS_MCP_SSP_CTRL0, CDNS_DEFAULT_SSP_INTERVAL);
+       cdns_writel(cdns, CDNS_MCP_SSP_CTRL1, CDNS_DEFAULT_SSP_INTERVAL);
+
+       /* Set cmd accept mode */
+       cdns_updatel(cdns, CDNS_MCP_CONTROL, CDNS_MCP_CONTROL_CMD_ACCEPT,
+                                       CDNS_MCP_CONTROL_CMD_ACCEPT);
+
+       /* Configure mcp config */
+       val = cdns_readl(cdns, CDNS_MCP_CONFIG);
+
+       /* Set Max cmd retry to 15 */
+       val |= CDNS_MCP_CONFIG_MCMD_RETRY;
+
+       /* Set frame delay between PREQ and ping frame to 15 frames */
+       val |= 0xF << SDW_REG_SHIFT(CDNS_MCP_CONFIG_MPREQ_DELAY);
+
+       /* Disable auto bus release */
+       val &= ~CDNS_MCP_CONFIG_BUS_REL;
+
+       /* Disable sniffer mode */
+       val &= ~CDNS_MCP_CONFIG_SNIFFER;
+
+       /* Set cmd mode for Tx and Rx cmds */
+       val &= ~CDNS_MCP_CONFIG_CMD;
+
+       /* Set operation to normal */
+       val &= ~CDNS_MCP_CONFIG_OP;
+       val |= CDNS_MCP_CONFIG_OP_NORMAL;
+
+       cdns_writel(cdns, CDNS_MCP_CONFIG, val);
+
+       return 0;
+}
+EXPORT_SYMBOL(sdw_cdns_init);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("Cadence Soundwire Library");
diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h
new file mode 100644 (file)
index 0000000..f723c33
--- /dev/null
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+#ifndef __SDW_CADENCE_H
+#define __SDW_CADENCE_H
+
+/**
+ * struct sdw_cdns - Cadence driver context
+ * @dev: Linux device
+ * @bus: Bus handle
+ * @instance: instance number
+ * @registers: Cadence registers
+ * @link_up: Link status
+ */
+struct sdw_cdns {
+       struct device *dev;
+       struct sdw_bus bus;
+       unsigned int instance;
+
+       void __iomem *registers;
+
+       bool link_up;
+};
+
+#define bus_to_cdns(_bus) container_of(_bus, struct sdw_cdns, bus)
+
+/* Exported symbols */
+
+irqreturn_t sdw_cdns_irq(int irq, void *dev_id);
+irqreturn_t sdw_cdns_thread(int irq, void *dev_id);
+
+int sdw_cdns_init(struct sdw_cdns *cdns);
+
+#endif /* __SDW_CADENCE_H */