openwrt/target/linux/bcm53xx/patches-3.14/180-spi-bcm53xx-driver-for-SPI-controller-on-Broadcom-bc.patch
Hauke Mehrtens f66a0912f7 bcm53xx: add SPI controller driver
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

SVN-Revision: 42223
2014-08-19 20:14:06 +00:00

436 lines
12 KiB
Diff

From a59f3fa1dd4cb284171a53cb7a614ad947c544f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
Date: Wed, 13 Aug 2014 14:11:39 +0200
Subject: [PATCH V2] spi: bcm53xx: driver for SPI controller on Broadcom bcma
SoC
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Broadcom 53xx ARM SoCs use bcma bus that contains various cores (AKA
devices). If board has a serial flash, it's connected over SPI and the
bcma bus includes a SPI controller. Example log from such a board:
bus0: Found chip with id 53010, rev 0x00 and package 0x02
(...)
bus0: Core 18 found: SPI flash controller (manuf 0x4BF, id 0x50A, rev 0x01, class 0x0)
This patch adds a bcma driver for SPI core, it registers SPI master
controller and "bcm53xxspiflash" SPI device.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
---
Since RFC: Add Signed-off-by
Update to compile on top of for-next
V2: Use wait timeout
Describe bcm53xxspi_calc_timeout a bit
Use devm_spi_register_master
Thanks Mark for your comments!
---
drivers/spi/Kconfig | 6 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-bcm53xx.c | 295 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/spi/spi-bcm53xx.h | 72 +++++++++++
4 files changed, 374 insertions(+)
create mode 100644 drivers/spi/spi-bcm53xx.c
create mode 100644 drivers/spi/spi-bcm53xx.h
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -112,6 +112,12 @@ config SPI_AU1550
If you say yes to this option, support will be included for the
PSC SPI controller found on Au1550, Au1200 and Au1300 series.
+config SPI_BCM53XX
+ tristate "Broadcom BCM53xx SPI controller"
+ depends on ARCH_BCM_5301X
+ help
+ Enable support for the SPI controller on Broadcom BCM53xx ARM SoCs.
+
config SPI_BCM63XX
tristate "Broadcom BCM63xx SPI controller"
depends on BCM63XX
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_SPI_ATMEL) += spi-atmel.o
obj-$(CONFIG_SPI_ATH79) += spi-ath79.o
obj-$(CONFIG_SPI_AU1550) += spi-au1550.o
obj-$(CONFIG_SPI_BCM2835) += spi-bcm2835.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_BFIN5XX) += spi-bfin5xx.o
--- /dev/null
+++ b/drivers/spi/spi-bcm53xx.c
@@ -0,0 +1,295 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/bcma/bcma.h>
+#include <linux/spi/spi.h>
+
+#include "spi-bcm53xx.h"
+
+#define BCM53XXSPI_MAX_SPI_BAUD 13500000 /* 216 MHz? */
+
+/* The longest observed required wait was 19 ms */
+#define BCM53XXSPI_SPE_TIMEOUT_MS 80
+
+struct bcm53xxspi {
+ struct bcma_device *core;
+ struct spi_master *master;
+
+ size_t read_offset;
+};
+
+static inline u32 bcm53xxspi_read(struct bcm53xxspi *b53spi, u16 offset)
+{
+ return bcma_read32(b53spi->core, offset);
+}
+
+static inline void bcm53xxspi_write(struct bcm53xxspi *b53spi, u16 offset,
+ u32 value)
+{
+ bcma_write32(b53spi->core, offset, value);
+}
+
+static inline unsigned int bcm53xxspi_calc_timeout(size_t len)
+{
+ /* Do some magic calculation based on length and buad. Add 10% and 1. */
+ return (len * 9000 / BCM53XXSPI_MAX_SPI_BAUD * 110 / 100) + 1;
+}
+
+static int bcm53xxspi_wait(struct bcm53xxspi *b53spi, unsigned int timeout_ms)
+{
+ unsigned long deadline;
+ u32 tmp;
+
+ /* SPE bit has to be 0 before we read MSPI STATUS */
+ deadline = jiffies + BCM53XXSPI_SPE_TIMEOUT_MS * HZ / 1000;
+ do {
+ tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2);
+ if (!(tmp & B53SPI_MSPI_SPCR2_SPE))
+ break;
+ udelay(5);
+ } while (!time_after_eq(jiffies, deadline));
+
+ if (tmp & B53SPI_MSPI_SPCR2_SPE)
+ goto spi_timeout;
+
+ /* Check status */
+ deadline = jiffies + timeout_ms * HZ / 1000;
+ do {
+ tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_MSPI_STATUS);
+ if (tmp & B53SPI_MSPI_MSPI_STATUS_SPIF) {
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_MSPI_STATUS, 0);
+ return 0;
+ }
+
+ cpu_relax();
+ udelay(100);
+ } while (!time_after_eq(jiffies, deadline));
+
+spi_timeout:
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_MSPI_STATUS, 0);
+
+ pr_err("Timeout waiting for SPI to be ready!\n");
+
+ return -EBUSY;
+}
+
+static void bcm53xxspi_buf_write(struct bcm53xxspi *b53spi, u8 *w_buf,
+ size_t len, bool cont)
+{
+ u32 tmp;
+ int i;
+
+ for (i = 0; i < len; i++) {
+ /* Transmit Register File MSB */
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_TXRAM + 4 * (i * 2),
+ (unsigned int)w_buf[i]);
+ }
+
+ for (i = 0; i < len; i++) {
+ tmp = B53SPI_CDRAM_CONT | B53SPI_CDRAM_PCS_DISABLE_ALL |
+ B53SPI_CDRAM_PCS_DSCK;
+ if (!cont && i == len - 1)
+ tmp &= ~B53SPI_CDRAM_CONT;
+ tmp &= ~0x1;
+ /* Command Register File */
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_CDRAM + 4 * i, tmp);
+ }
+
+ /* Set queue pointers */
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_NEWQP, 0);
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_ENDQP, len - 1);
+
+ if (cont)
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 1);
+
+ /* Start SPI transfer */
+ tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2);
+ tmp |= B53SPI_MSPI_SPCR2_SPE;
+ if (cont)
+ tmp |= B53SPI_MSPI_SPCR2_CONT_AFTER_CMD;
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_SPCR2, tmp);
+
+ /* Wait for SPI to finish */
+ bcm53xxspi_wait(b53spi, bcm53xxspi_calc_timeout(len));
+
+ if (!cont)
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 0);
+
+ b53spi->read_offset = len;
+}
+
+static void bcm53xxspi_buf_read(struct bcm53xxspi *b53spi, u8 *r_buf,
+ size_t len, bool cont)
+{
+ u32 tmp;
+ int i;
+
+ for (i = 0; i < b53spi->read_offset + len; i++) {
+ tmp = B53SPI_CDRAM_CONT | B53SPI_CDRAM_PCS_DISABLE_ALL |
+ B53SPI_CDRAM_PCS_DSCK;
+ if (!cont && i == b53spi->read_offset + len - 1)
+ tmp &= ~B53SPI_CDRAM_CONT;
+ tmp &= ~0x1;
+ /* Command Register File */
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_CDRAM + 4 * i, tmp);
+ }
+
+ /* Set queue pointers */
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_NEWQP, 0);
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_ENDQP,
+ b53spi->read_offset + len - 1);
+
+ if (cont)
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 1);
+
+ /* Start SPI transfer */
+ tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2);
+ tmp |= B53SPI_MSPI_SPCR2_SPE;
+ if (cont)
+ tmp |= B53SPI_MSPI_SPCR2_CONT_AFTER_CMD;
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_SPCR2, tmp);
+
+ /* Wait for SPI to finish */
+ bcm53xxspi_wait(b53spi, bcm53xxspi_calc_timeout(len));
+
+ if (!cont)
+ bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 0);
+
+ for (i = 0; i < len; ++i) {
+ int offset = b53spi->read_offset + i;
+
+ /* Data stored in the transmit register file LSB */
+ r_buf[i] = (u8)bcm53xxspi_read(b53spi, B53SPI_MSPI_RXRAM + 4 * (1 + offset * 2));
+ }
+
+ b53spi->read_offset = 0;
+}
+
+static int bcm53xxspi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct bcm53xxspi *b53spi = spi_master_get_devdata(master);
+ u8 *buf;
+ size_t left;
+
+ if (t->tx_buf) {
+ buf = (u8 *)t->tx_buf;
+ left = t->len;
+ while (left) {
+ size_t to_write = min_t(size_t, 16, left);
+ bool cont = left - to_write > 0;
+
+ bcm53xxspi_buf_write(b53spi, buf, to_write, cont);
+ left -= to_write;
+ buf += to_write;
+ }
+ }
+
+ if (t->rx_buf) {
+ buf = (u8 *)t->rx_buf;
+ left = t->len;
+ while (left) {
+ size_t to_read = min_t(size_t, 16 - b53spi->read_offset,
+ left);
+ bool cont = left - to_read > 0;
+
+ bcm53xxspi_buf_read(b53spi, buf, to_read, cont);
+ left -= to_read;
+ buf += to_read;
+ }
+ }
+
+ return 0;
+}
+
+/**************************************************
+ * BCMA
+ **************************************************/
+
+struct spi_board_info bcm53xx_info = {
+ .modalias = "bcm53xxspiflash",
+};
+
+static const struct bcma_device_id bcm53xxspi_bcma_tbl[] = {
+ BCMA_CORE(BCMA_MANUF_BCM, BCMA_CORE_NS_QSPI, BCMA_ANY_REV, BCMA_ANY_CLASS),
+ BCMA_CORETABLE_END
+};
+MODULE_DEVICE_TABLE(bcma, bcm53xxspi_bcma_tbl);
+
+static int bcm53xxspi_bcma_probe(struct bcma_device *core)
+{
+ struct bcm53xxspi *b53spi;
+ struct spi_master *master;
+ int err;
+
+ if (core->bus->drv_cc.core->id.rev != 42) {
+ pr_err("SPI on SoC with unsupported ChipCommon rev\n");
+ return -ENOTSUPP;
+ }
+
+ master = spi_alloc_master(&core->dev, sizeof(*b53spi));
+ if (!master)
+ return -ENOMEM;
+
+ b53spi = spi_master_get_devdata(master);
+ b53spi->master = master;
+ b53spi->core = core;
+
+ master->transfer_one = bcm53xxspi_transfer_one;
+
+ bcma_set_drvdata(core, b53spi);
+
+ err = devm_spi_register_master(&core->dev, master);
+ if (err) {
+ spi_master_put(master);
+ bcma_set_drvdata(core, NULL);
+ goto out;
+ }
+
+ /* Broadcom SoCs (at least with the CC rev 42) use SPI for flash only */
+ spi_new_device(master, &bcm53xx_info);
+
+out:
+ return err;
+}
+
+static void bcm53xxspi_bcma_remove(struct bcma_device *core)
+{
+ struct bcm53xxspi *b53spi = bcma_get_drvdata(core);
+
+ spi_unregister_master(b53spi->master);
+}
+
+static struct bcma_driver bcm53xxspi_bcma_driver = {
+ .name = KBUILD_MODNAME,
+ .id_table = bcm53xxspi_bcma_tbl,
+ .probe = bcm53xxspi_bcma_probe,
+ .remove = bcm53xxspi_bcma_remove,
+};
+
+/**************************************************
+ * Init & exit
+ **************************************************/
+
+static int __init bcm53xxspi_module_init(void)
+{
+ int err = 0;
+
+ err = bcma_driver_register(&bcm53xxspi_bcma_driver);
+ if (err)
+ pr_err("Failed to register bcma driver: %d\n", err);
+
+ return err;
+}
+
+static void __exit bcm53xxspi_module_exit(void)
+{
+ bcma_driver_unregister(&bcm53xxspi_bcma_driver);
+}
+
+module_init(bcm53xxspi_module_init);
+module_exit(bcm53xxspi_module_exit);
--- /dev/null
+++ b/drivers/spi/spi-bcm53xx.h
@@ -0,0 +1,72 @@
+#ifndef SPI_BCM53XX_H
+#define SPI_BCM53XX_H
+
+#define B53SPI_BSPI_REVISION_ID 0x000
+#define B53SPI_BSPI_SCRATCH 0x004
+#define B53SPI_BSPI_MAST_N_BOOT_CTRL 0x008
+#define B53SPI_BSPI_BUSY_STATUS 0x00c
+#define B53SPI_BSPI_INTR_STATUS 0x010
+#define B53SPI_BSPI_B0_STATUS 0x014
+#define B53SPI_BSPI_B0_CTRL 0x018
+#define B53SPI_BSPI_B1_STATUS 0x01c
+#define B53SPI_BSPI_B1_CTRL 0x020
+#define B53SPI_BSPI_STRAP_OVERRIDE_CTRL 0x024
+#define B53SPI_BSPI_FLEX_MODE_ENABLE 0x028
+#define B53SPI_BSPI_BITS_PER_CYCLE 0x02c
+#define B53SPI_BSPI_BITS_PER_PHASE 0x030
+#define B53SPI_BSPI_CMD_AND_MODE_BYTE 0x034
+#define B53SPI_BSPI_BSPI_FLASH_UPPER_ADDR_BYTE 0x038
+#define B53SPI_BSPI_BSPI_XOR_VALUE 0x03c
+#define B53SPI_BSPI_BSPI_XOR_ENABLE 0x040
+#define B53SPI_BSPI_BSPI_PIO_MODE_ENABLE 0x044
+#define B53SPI_BSPI_BSPI_PIO_IODIR 0x048
+#define B53SPI_BSPI_BSPI_PIO_DATA 0x04c
+
+/* RAF */
+#define B53SPI_RAF_START_ADDR 0x100
+#define B53SPI_RAF_NUM_WORDS 0x104
+#define B53SPI_RAF_CTRL 0x108
+#define B53SPI_RAF_FULLNESS 0x10c
+#define B53SPI_RAF_WATERMARK 0x110
+#define B53SPI_RAF_STATUS 0x114
+#define B53SPI_RAF_READ_DATA 0x118
+#define B53SPI_RAF_WORD_CNT 0x11c
+#define B53SPI_RAF_CURR_ADDR 0x120
+
+/* MSPI */
+#define B53SPI_MSPI_SPCR0_LSB 0x200
+#define B53SPI_MSPI_SPCR0_MSB 0x204
+#define B53SPI_MSPI_SPCR1_LSB 0x208
+#define B53SPI_MSPI_SPCR1_MSB 0x20c
+#define B53SPI_MSPI_NEWQP 0x210
+#define B53SPI_MSPI_ENDQP 0x214
+#define B53SPI_MSPI_SPCR2 0x218
+#define B53SPI_MSPI_SPCR2_SPE 0x00000040
+#define B53SPI_MSPI_SPCR2_CONT_AFTER_CMD 0x00000080
+#define B53SPI_MSPI_MSPI_STATUS 0x220
+#define B53SPI_MSPI_MSPI_STATUS_SPIF 0x00000001
+#define B53SPI_MSPI_CPTQP 0x224
+#define B53SPI_MSPI_TXRAM 0x240 /* 32 registers, up to 0x2b8 */
+#define B53SPI_MSPI_RXRAM 0x2c0 /* 32 registers, up to 0x33c */
+#define B53SPI_MSPI_CDRAM 0x340 /* 16 registers, up to 0x37c */
+#define B53SPI_CDRAM_PCS_PCS0 0x00000001
+#define B53SPI_CDRAM_PCS_PCS1 0x00000002
+#define B53SPI_CDRAM_PCS_PCS2 0x00000004
+#define B53SPI_CDRAM_PCS_PCS3 0x00000008
+#define B53SPI_CDRAM_PCS_DISABLE_ALL 0x0000000f
+#define B53SPI_CDRAM_PCS_DSCK 0x00000010
+#define B53SPI_CDRAM_BITSE 0x00000040
+#define B53SPI_CDRAM_CONT 0x00000080
+#define B53SPI_MSPI_WRITE_LOCK 0x380
+#define B53SPI_MSPI_DISABLE_FLUSH_GEN 0x384
+
+/* Interrupt */
+#define B53SPI_INTR_RAF_LR_FULLNESS_REACHED 0x3a0
+#define B53SPI_INTR_RAF_LR_TRUNCATED 0x3a4
+#define B53SPI_INTR_RAF_LR_IMPATIENT 0x3a8
+#define B53SPI_INTR_RAF_LR_SESSION_DONE 0x3ac
+#define B53SPI_INTR_RAF_LR_OVERREAD 0x3b0
+#define B53SPI_INTR_MSPI_DONE 0x3b4
+#define B53SPI_INTR_MSPI_HALT_SET_TRANSACTION_DONE 0x3b8
+
+#endif /* SPI_BCM53XX_H */