spi: iproc-qspi: Add Broadcom iProc SoCs support
authorKamal Dasu <kdasu.kdev@gmail.com>
Wed, 24 Aug 2016 22:04:29 +0000 (18:04 -0400)
committerMark Brown <broonie@kernel.org>
Sat, 24 Sep 2016 19:03:25 +0000 (20:03 +0100)
This spi driver uses the common spi-bcm-qspi driver and implements iProc
SoCs specific interrupt controller. The common driver now calls the SoC
handlers when present. Adding support for both muxed l1 and unmuxed interrupt
sources.

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/Makefile
drivers/spi/spi-bcm-qspi.c
drivers/spi/spi-bcm-qspi.h
drivers/spi/spi-iproc-qspi.c [new file with mode: 0644]

index 3e753db..2dc1b71 100644 (file)
@@ -21,7 +21,7 @@ obj-$(CONFIG_SPI_BCM2835AUX)          += spi-bcm2835aux.o
 obj-$(CONFIG_SPI_BCM53XX)              += spi-bcm53xx.o
 obj-$(CONFIG_SPI_BCM63XX)              += spi-bcm63xx.o
 obj-$(CONFIG_SPI_BCM63XX_HSSPI)                += spi-bcm63xx-hsspi.o
-obj-$(CONFIG_SPI_BCM_QSPI)             += spi-brcmstb-qspi.o spi-bcm-qspi.o
+obj-$(CONFIG_SPI_BCM_QSPI)             += spi-iproc-qspi.o spi-brcmstb-qspi.o spi-bcm-qspi.o
 obj-$(CONFIG_SPI_BFIN5XX)              += spi-bfin5xx.o
 obj-$(CONFIG_SPI_ADI_V3)                += spi-adi-v3.o
 obj-$(CONFIG_SPI_BFIN_SPORT)           += spi-bfin-sport.o
index 2c121ba..14f9dea 100644 (file)
@@ -175,9 +175,15 @@ enum base_type {
        BASEMAX,
 };
 
+enum irq_source {
+       SINGLE_L2,
+       MUXED_L1,
+};
+
 struct bcm_qspi_irq {
        const char *irq_name;
        const irq_handler_t irq_handler;
+       int irq_source;
        u32 mask;
 };
 
@@ -198,6 +204,10 @@ struct bcm_qspi {
        u32 base_clk;
        u32 max_speed_hz;
        void __iomem *base[BASEMAX];
+
+       /* Some SoCs provide custom interrupt status register(s) */
+       struct bcm_qspi_soc_intc        *soc_intc;
+
        struct bcm_qspi_parms last_parms;
        struct qspi_trans  trans_pos;
        int curr_cs;
@@ -806,6 +816,7 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
        u32 addr = 0, len, len_words;
        int ret = 0;
        unsigned long timeo = msecs_to_jiffies(100);
+       struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
 
        if (bcm_qspi_bspi_ver_three(qspi))
                if (msg->addr_width == BSPI_ADDRLEN_4BYTES)
@@ -850,6 +861,15 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
        bcm_qspi_write(qspi, BSPI, BSPI_RAF_NUM_WORDS, len_words);
        bcm_qspi_write(qspi, BSPI, BSPI_RAF_WATERMARK, 0);
 
+       if (qspi->soc_intc) {
+               /*
+                * clear soc MSPI and BSPI interrupts and enable
+                * BSPI interrupts.
+                */
+               soc_intc->bcm_qspi_int_ack(soc_intc, MSPI_BSPI_DONE);
+               soc_intc->bcm_qspi_int_set(soc_intc, BSPI_DONE, true);
+       }
+
        /* Must flush previous writes before starting BSPI operation */
        mb();
 
@@ -952,9 +972,12 @@ static irqreturn_t bcm_qspi_mspi_l2_isr(int irq, void *dev_id)
        u32 status = bcm_qspi_read(qspi, MSPI, MSPI_MSPI_STATUS);
 
        if (status & MSPI_MSPI_STATUS_SPIF) {
+               struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
                /* clear interrupt */
                status &= ~MSPI_MSPI_STATUS_SPIF;
                bcm_qspi_write(qspi, MSPI, MSPI_MSPI_STATUS, status);
+               if (qspi->soc_intc)
+                       soc_intc->bcm_qspi_int_ack(soc_intc, MSPI_DONE);
                complete(&qspi->mspi_done);
                return IRQ_HANDLED;
        }
@@ -966,20 +989,33 @@ static irqreturn_t bcm_qspi_bspi_lr_l2_isr(int irq, void *dev_id)
 {
        struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
        struct bcm_qspi *qspi = qspi_dev_id->dev;
-       u32 status;
+       struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
+       u32 status = qspi_dev_id->irqp->mask;
 
        if (qspi->bspi_enabled && qspi->bspi_rf_msg) {
                bcm_qspi_bspi_lr_data_read(qspi);
                if (qspi->bspi_rf_msg_len == 0) {
                        qspi->bspi_rf_msg = NULL;
+                       if (qspi->soc_intc) {
+                               /* disable soc BSPI interrupt */
+                               soc_intc->bcm_qspi_int_set(soc_intc, BSPI_DONE,
+                                                          false);
+                               /* indicate done */
+                               status = INTR_BSPI_LR_SESSION_DONE_MASK;
+                       }
+
                        if (qspi->bspi_rf_msg_status)
                                bcm_qspi_bspi_lr_clear(qspi);
                        else
                                bcm_qspi_bspi_flush_prefetch_buffers(qspi);
                }
+
+               if (qspi->soc_intc)
+                       /* clear soc BSPI interrupt */
+                       soc_intc->bcm_qspi_int_ack(soc_intc, BSPI_DONE);
        }
 
-       status = (qspi_dev_id->irqp->mask & INTR_BSPI_LR_SESSION_DONE_MASK);
+       status &= INTR_BSPI_LR_SESSION_DONE_MASK;
        if (qspi->bspi_enabled && status && qspi->bspi_rf_msg_len == 0)
                complete(&qspi->bspi_done);
 
@@ -990,13 +1026,39 @@ static irqreturn_t bcm_qspi_bspi_lr_err_l2_isr(int irq, void *dev_id)
 {
        struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
        struct bcm_qspi *qspi = qspi_dev_id->dev;
+       struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
 
        dev_err(&qspi->pdev->dev, "BSPI INT error\n");
        qspi->bspi_rf_msg_status = -EIO;
+       if (qspi->soc_intc)
+               /* clear soc interrupt */
+               soc_intc->bcm_qspi_int_ack(soc_intc, BSPI_ERR);
+
        complete(&qspi->bspi_done);
        return IRQ_HANDLED;
 }
 
+static irqreturn_t bcm_qspi_l1_isr(int irq, void *dev_id)
+{
+       struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
+       struct bcm_qspi *qspi = qspi_dev_id->dev;
+       struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
+       irqreturn_t ret = IRQ_NONE;
+
+       if (soc_intc) {
+               u32 status = soc_intc->bcm_qspi_get_int_status(soc_intc);
+
+               if (status & MSPI_DONE)
+                       ret = bcm_qspi_mspi_l2_isr(irq, dev_id);
+               else if (status & BSPI_DONE)
+                       ret = bcm_qspi_bspi_lr_l2_isr(irq, dev_id);
+               else if (status & BSPI_ERR)
+                       ret = bcm_qspi_bspi_lr_err_l2_isr(irq, dev_id);
+       }
+
+       return ret;
+}
+
 static const struct bcm_qspi_irq qspi_irq_tab[] = {
        {
                .irq_name = "spi_lr_fullness_reached",
@@ -1036,6 +1098,13 @@ static const struct bcm_qspi_irq qspi_irq_tab[] = {
                .irq_handler = bcm_qspi_mspi_l2_isr,
                .mask = INTR_MSPI_HALTED_MASK,
        },
+       {
+               /* single muxed L1 interrupt source */
+               .irq_name = "spi_l1_intr",
+               .irq_handler = bcm_qspi_l1_isr,
+               .irq_source = MUXED_L1,
+               .mask = QSPI_INTERRUPTS_ALL,
+       },
 };
 
 static void bcm_qspi_bspi_init(struct bcm_qspi *qspi)
@@ -1182,7 +1251,13 @@ int bcm_qspi_probe(struct platform_device *pdev,
        for (val = 0; val < num_irqs; val++) {
                irq = -1;
                name = qspi_irq_tab[val].irq_name;
-               irq = platform_get_irq_byname(pdev, name);
+               if (qspi_irq_tab[val].irq_source == SINGLE_L2) {
+                       /* get the l2 interrupts */
+                       irq = platform_get_irq_byname(pdev, name);
+               } else if (!num_ints && soc_intc) {
+                       /* all mspi, bspi intrs muxed to one L1 intr */
+                       irq = platform_get_irq(pdev, 0);
+               }
 
                if (irq  >= 0) {
                        ret = devm_request_irq(&pdev->dev, irq,
@@ -1209,6 +1284,17 @@ int bcm_qspi_probe(struct platform_device *pdev,
                goto qspi_probe_err;
        }
 
+       /*
+        * Some SoCs integrate spi controller (e.g., its interrupt bits)
+        * in specific ways
+        */
+       if (soc_intc) {
+               qspi->soc_intc = soc_intc;
+               soc_intc->bcm_qspi_int_set(soc_intc, MSPI_DONE, true);
+       } else {
+               qspi->soc_intc = NULL;
+       }
+
        qspi->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(qspi->clk)) {
                dev_warn(dev, "unable to get clock\n");
@@ -1288,6 +1374,11 @@ static int __maybe_unused bcm_qspi_resume(struct device *dev)
 
        bcm_qspi_hw_init(qspi);
        bcm_qspi_chip_select(qspi, qspi->curr_cs);
+       if (qspi->soc_intc)
+               /* enable MSPI interrupt */
+               qspi->soc_intc->bcm_qspi_int_set(qspi->soc_intc, MSPI_DONE,
+                                                true);
+
        ret = clk_enable(qspi->clk);
        if (!ret)
                spi_master_resume(qspi->master);
index 65c363b..7abfc75 100644 (file)
        (INTR_MSPI_DONE_MASK |                 \
         INTR_MSPI_HALTED_MASK)
 
+#define QSPI_INTERRUPTS_ALL                    \
+       (MSPI_INTERRUPTS_ALL |                 \
+        BSPI_LR_INTERRUPTS_ALL)
+
 struct platform_device;
 struct dev_pm_ops;
 
-struct bcm_qspi_soc_intc;
+enum {
+       MSPI_DONE = 0x1,
+       BSPI_DONE = 0x2,
+       BSPI_ERR = 0x4,
+       MSPI_BSPI_DONE = 0x7
+};
+
+struct bcm_qspi_soc_intc {
+       void (*bcm_qspi_int_ack)(struct bcm_qspi_soc_intc *soc_intc, int type);
+       void (*bcm_qspi_int_set)(struct bcm_qspi_soc_intc *soc_intc, int type,
+                                bool en);
+       u32 (*bcm_qspi_get_int_status)(struct bcm_qspi_soc_intc *soc_intc);
+};
 
 /* Read controller register*/
 static inline u32 bcm_qspi_readl(bool be, void __iomem *addr)
@@ -72,6 +88,22 @@ static inline void bcm_qspi_writel(bool be,
                writel_relaxed(data, addr);
 }
 
+static inline u32 get_qspi_mask(int type)
+{
+       switch (type) {
+       case MSPI_DONE:
+               return INTR_MSPI_DONE_MASK;
+       case BSPI_DONE:
+               return BSPI_LR_INTERRUPTS_ALL;
+       case MSPI_BSPI_DONE:
+               return QSPI_INTERRUPTS_ALL;
+       case BSPI_ERR:
+               return BSPI_LR_INTERRUPTS_ERROR;
+       }
+
+       return 0;
+}
+
 /* The common driver functions to be called by the SoC platform driver */
 int bcm_qspi_probe(struct platform_device *pdev,
                   struct bcm_qspi_soc_intc *soc_intc);
diff --git a/drivers/spi/spi-iproc-qspi.c b/drivers/spi/spi-iproc-qspi.c
new file mode 100644 (file)
index 0000000..be6ccb2
--- /dev/null
@@ -0,0 +1,163 @@
+/*
+ * Copyright 2016 Broadcom Limited
+ *
+ * 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.
+ *
+ * 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 for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "spi-bcm-qspi.h"
+
+#define INTR_BASE_BIT_SHIFT                    0x02
+#define INTR_COUNT                             0x07
+
+struct bcm_iproc_intc {
+       struct bcm_qspi_soc_intc soc_intc;
+       struct platform_device *pdev;
+       void __iomem *int_reg;
+       void __iomem *int_status_reg;
+       spinlock_t soclock;
+       bool big_endian;
+};
+
+static u32 bcm_iproc_qspi_get_l2_int_status(struct bcm_qspi_soc_intc *soc_intc)
+{
+       struct bcm_iproc_intc *priv =
+                       container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+       void __iomem *mmio = priv->int_status_reg;
+       int i;
+       u32 val = 0, sts = 0;
+
+       for (i = 0; i < INTR_COUNT; i++) {
+               if (bcm_qspi_readl(priv->big_endian, mmio + (i * 4)))
+                       val |= 1UL << i;
+       }
+
+       if (val & INTR_MSPI_DONE_MASK)
+               sts |= MSPI_DONE;
+
+       if (val & BSPI_LR_INTERRUPTS_ALL)
+               sts |= BSPI_DONE;
+
+       if (val & BSPI_LR_INTERRUPTS_ERROR)
+               sts |= BSPI_ERR;
+
+       return sts;
+}
+
+static void bcm_iproc_qspi_int_ack(struct bcm_qspi_soc_intc *soc_intc, int type)
+{
+       struct bcm_iproc_intc *priv =
+                       container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+       void __iomem *mmio = priv->int_status_reg;
+       u32 mask = get_qspi_mask(type);
+       int i;
+
+       for (i = 0; i < INTR_COUNT; i++) {
+               if (mask & (1UL << i))
+                       bcm_qspi_writel(priv->big_endian, 1, mmio + (i * 4));
+       }
+}
+
+static void bcm_iproc_qspi_int_set(struct bcm_qspi_soc_intc *soc_intc, int type,
+                                  bool en)
+{
+       struct bcm_iproc_intc *priv =
+                       container_of(soc_intc, struct bcm_iproc_intc, soc_intc);
+       void __iomem *mmio = priv->int_reg;
+       u32 mask = get_qspi_mask(type);
+       u32 val;
+       unsigned long flags;
+
+       spin_lock_irqsave(&priv->soclock, flags);
+
+       val = bcm_qspi_readl(priv->big_endian, mmio);
+
+       if (en)
+               val = val | (mask << INTR_BASE_BIT_SHIFT);
+       else
+               val = val & ~(mask << INTR_BASE_BIT_SHIFT);
+
+       bcm_qspi_writel(priv->big_endian, val, mmio);
+
+       spin_unlock_irqrestore(&priv->soclock, flags);
+}
+
+static int bcm_iproc_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct bcm_iproc_intc *priv;
+       struct bcm_qspi_soc_intc *soc_intc;
+       struct resource *res;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+       soc_intc = &priv->soc_intc;
+       priv->pdev = pdev;
+
+       spin_lock_init(&priv->soclock);
+
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "intr_regs");
+       priv->int_reg = devm_ioremap_resource(dev, res);
+       if (IS_ERR(priv->int_reg))
+               return PTR_ERR(priv->int_reg);
+
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+                                          "intr_status_reg");
+       priv->int_status_reg = devm_ioremap_resource(dev, res);
+       if (IS_ERR(priv->int_status_reg))
+               return PTR_ERR(priv->int_status_reg);
+
+       priv->big_endian = of_device_is_big_endian(dev->of_node);
+
+       bcm_iproc_qspi_int_ack(soc_intc, MSPI_BSPI_DONE);
+       bcm_iproc_qspi_int_set(soc_intc, MSPI_BSPI_DONE, false);
+
+       soc_intc->bcm_qspi_int_ack = bcm_iproc_qspi_int_ack;
+       soc_intc->bcm_qspi_int_set = bcm_iproc_qspi_int_set;
+       soc_intc->bcm_qspi_get_int_status = bcm_iproc_qspi_get_l2_int_status;
+
+       return bcm_qspi_probe(pdev, soc_intc);
+}
+
+static int bcm_iproc_remove(struct platform_device *pdev)
+{
+       return bcm_qspi_remove(pdev);
+}
+
+static const struct of_device_id bcm_iproc_of_match[] = {
+       { .compatible = "brcm,spi-nsp-qspi" },
+       { .compatible = "brcm,spi-ns2-qspi" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, bcm_iproc_of_match);
+
+static struct platform_driver bcm_iproc_driver = {
+       .probe                  = bcm_iproc_probe,
+       .remove                 = bcm_iproc_remove,
+       .driver = {
+               .name           = "bcm_iproc",
+               .pm             = &bcm_qspi_pm_ops,
+               .of_match_table = bcm_iproc_of_match,
+       }
+};
+module_platform_driver(bcm_iproc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Kamal Dasu");
+MODULE_DESCRIPTION("SPI flash driver for Broadcom iProc SoCs");