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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/spi/spi-nxp-fspi.c
parentInitial commit. (diff)
downloadlinux-430c2fc249ea5c0536abd21c23382884005c9093.tar.xz
linux-430c2fc249ea5c0536abd21c23382884005c9093.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/spi/spi-nxp-fspi.c')
-rw-r--r--drivers/spi/spi-nxp-fspi.c1195
1 files changed, 1195 insertions, 0 deletions
diff --git a/drivers/spi/spi-nxp-fspi.c b/drivers/spi/spi-nxp-fspi.c
new file mode 100644
index 000000000..f40b93960
--- /dev/null
+++ b/drivers/spi/spi-nxp-fspi.c
@@ -0,0 +1,1195 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * NXP FlexSPI(FSPI) controller driver.
+ *
+ * Copyright 2019-2020 NXP
+ * Copyright 2020 Puresoftware Ltd.
+ *
+ * FlexSPI is a flexsible SPI host controller which supports two SPI
+ * channels and up to 4 external devices. Each channel supports
+ * Single/Dual/Quad/Octal mode data transfer (1/2/4/8 bidirectional
+ * data lines).
+ *
+ * FlexSPI controller is driven by the LUT(Look-up Table) registers
+ * LUT registers are a look-up-table for sequences of instructions.
+ * A valid sequence consists of four LUT registers.
+ * Maximum 32 LUT sequences can be programmed simultaneously.
+ *
+ * LUTs are being created at run-time based on the commands passed
+ * from the spi-mem framework, thus using single LUT index.
+ *
+ * Software triggered Flash read/write access by IP Bus.
+ *
+ * Memory mapped read access by AHB Bus.
+ *
+ * Based on SPI MEM interface and spi-fsl-qspi.c driver.
+ *
+ * Author:
+ * Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>
+ * Boris Brezillon <bbrezillon@kernel.org>
+ * Frieder Schrempf <frieder.schrempf@kontron.de>
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_qos.h>
+#include <linux/sizes.h>
+
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+/*
+ * The driver only uses one single LUT entry, that is updated on
+ * each call of exec_op(). Index 0 is preset at boot with a basic
+ * read operation, so let's use the last entry (31).
+ */
+#define SEQID_LUT 31
+
+/* Registers used by the driver */
+#define FSPI_MCR0 0x00
+#define FSPI_MCR0_AHB_TIMEOUT(x) ((x) << 24)
+#define FSPI_MCR0_IP_TIMEOUT(x) ((x) << 16)
+#define FSPI_MCR0_LEARN_EN BIT(15)
+#define FSPI_MCR0_SCRFRUN_EN BIT(14)
+#define FSPI_MCR0_OCTCOMB_EN BIT(13)
+#define FSPI_MCR0_DOZE_EN BIT(12)
+#define FSPI_MCR0_HSEN BIT(11)
+#define FSPI_MCR0_SERCLKDIV BIT(8)
+#define FSPI_MCR0_ATDF_EN BIT(7)
+#define FSPI_MCR0_ARDF_EN BIT(6)
+#define FSPI_MCR0_RXCLKSRC(x) ((x) << 4)
+#define FSPI_MCR0_END_CFG(x) ((x) << 2)
+#define FSPI_MCR0_MDIS BIT(1)
+#define FSPI_MCR0_SWRST BIT(0)
+
+#define FSPI_MCR1 0x04
+#define FSPI_MCR1_SEQ_TIMEOUT(x) ((x) << 16)
+#define FSPI_MCR1_AHB_TIMEOUT(x) (x)
+
+#define FSPI_MCR2 0x08
+#define FSPI_MCR2_IDLE_WAIT(x) ((x) << 24)
+#define FSPI_MCR2_SAMEDEVICEEN BIT(15)
+#define FSPI_MCR2_CLRLRPHS BIT(14)
+#define FSPI_MCR2_ABRDATSZ BIT(8)
+#define FSPI_MCR2_ABRLEARN BIT(7)
+#define FSPI_MCR2_ABR_READ BIT(6)
+#define FSPI_MCR2_ABRWRITE BIT(5)
+#define FSPI_MCR2_ABRDUMMY BIT(4)
+#define FSPI_MCR2_ABR_MODE BIT(3)
+#define FSPI_MCR2_ABRCADDR BIT(2)
+#define FSPI_MCR2_ABRRADDR BIT(1)
+#define FSPI_MCR2_ABR_CMD BIT(0)
+
+#define FSPI_AHBCR 0x0c
+#define FSPI_AHBCR_RDADDROPT BIT(6)
+#define FSPI_AHBCR_PREF_EN BIT(5)
+#define FSPI_AHBCR_BUFF_EN BIT(4)
+#define FSPI_AHBCR_CACH_EN BIT(3)
+#define FSPI_AHBCR_CLRTXBUF BIT(2)
+#define FSPI_AHBCR_CLRRXBUF BIT(1)
+#define FSPI_AHBCR_PAR_EN BIT(0)
+
+#define FSPI_INTEN 0x10
+#define FSPI_INTEN_SCLKSBWR BIT(9)
+#define FSPI_INTEN_SCLKSBRD BIT(8)
+#define FSPI_INTEN_DATALRNFL BIT(7)
+#define FSPI_INTEN_IPTXWE BIT(6)
+#define FSPI_INTEN_IPRXWA BIT(5)
+#define FSPI_INTEN_AHBCMDERR BIT(4)
+#define FSPI_INTEN_IPCMDERR BIT(3)
+#define FSPI_INTEN_AHBCMDGE BIT(2)
+#define FSPI_INTEN_IPCMDGE BIT(1)
+#define FSPI_INTEN_IPCMDDONE BIT(0)
+
+#define FSPI_INTR 0x14
+#define FSPI_INTR_SCLKSBWR BIT(9)
+#define FSPI_INTR_SCLKSBRD BIT(8)
+#define FSPI_INTR_DATALRNFL BIT(7)
+#define FSPI_INTR_IPTXWE BIT(6)
+#define FSPI_INTR_IPRXWA BIT(5)
+#define FSPI_INTR_AHBCMDERR BIT(4)
+#define FSPI_INTR_IPCMDERR BIT(3)
+#define FSPI_INTR_AHBCMDGE BIT(2)
+#define FSPI_INTR_IPCMDGE BIT(1)
+#define FSPI_INTR_IPCMDDONE BIT(0)
+
+#define FSPI_LUTKEY 0x18
+#define FSPI_LUTKEY_VALUE 0x5AF05AF0
+
+#define FSPI_LCKCR 0x1C
+
+#define FSPI_LCKER_LOCK 0x1
+#define FSPI_LCKER_UNLOCK 0x2
+
+#define FSPI_BUFXCR_INVALID_MSTRID 0xE
+#define FSPI_AHBRX_BUF0CR0 0x20
+#define FSPI_AHBRX_BUF1CR0 0x24
+#define FSPI_AHBRX_BUF2CR0 0x28
+#define FSPI_AHBRX_BUF3CR0 0x2C
+#define FSPI_AHBRX_BUF4CR0 0x30
+#define FSPI_AHBRX_BUF5CR0 0x34
+#define FSPI_AHBRX_BUF6CR0 0x38
+#define FSPI_AHBRX_BUF7CR0 0x3C
+#define FSPI_AHBRXBUF0CR7_PREF BIT(31)
+
+#define FSPI_AHBRX_BUF0CR1 0x40
+#define FSPI_AHBRX_BUF1CR1 0x44
+#define FSPI_AHBRX_BUF2CR1 0x48
+#define FSPI_AHBRX_BUF3CR1 0x4C
+#define FSPI_AHBRX_BUF4CR1 0x50
+#define FSPI_AHBRX_BUF5CR1 0x54
+#define FSPI_AHBRX_BUF6CR1 0x58
+#define FSPI_AHBRX_BUF7CR1 0x5C
+
+#define FSPI_FLSHA1CR0 0x60
+#define FSPI_FLSHA2CR0 0x64
+#define FSPI_FLSHB1CR0 0x68
+#define FSPI_FLSHB2CR0 0x6C
+#define FSPI_FLSHXCR0_SZ_KB 10
+#define FSPI_FLSHXCR0_SZ(x) ((x) >> FSPI_FLSHXCR0_SZ_KB)
+
+#define FSPI_FLSHA1CR1 0x70
+#define FSPI_FLSHA2CR1 0x74
+#define FSPI_FLSHB1CR1 0x78
+#define FSPI_FLSHB2CR1 0x7C
+#define FSPI_FLSHXCR1_CSINTR(x) ((x) << 16)
+#define FSPI_FLSHXCR1_CAS(x) ((x) << 11)
+#define FSPI_FLSHXCR1_WA BIT(10)
+#define FSPI_FLSHXCR1_TCSH(x) ((x) << 5)
+#define FSPI_FLSHXCR1_TCSS(x) (x)
+
+#define FSPI_FLSHA1CR2 0x80
+#define FSPI_FLSHA2CR2 0x84
+#define FSPI_FLSHB1CR2 0x88
+#define FSPI_FLSHB2CR2 0x8C
+#define FSPI_FLSHXCR2_CLRINSP BIT(24)
+#define FSPI_FLSHXCR2_AWRWAIT BIT(16)
+#define FSPI_FLSHXCR2_AWRSEQN_SHIFT 13
+#define FSPI_FLSHXCR2_AWRSEQI_SHIFT 8
+#define FSPI_FLSHXCR2_ARDSEQN_SHIFT 5
+#define FSPI_FLSHXCR2_ARDSEQI_SHIFT 0
+
+#define FSPI_IPCR0 0xA0
+
+#define FSPI_IPCR1 0xA4
+#define FSPI_IPCR1_IPAREN BIT(31)
+#define FSPI_IPCR1_SEQNUM_SHIFT 24
+#define FSPI_IPCR1_SEQID_SHIFT 16
+#define FSPI_IPCR1_IDATSZ(x) (x)
+
+#define FSPI_IPCMD 0xB0
+#define FSPI_IPCMD_TRG BIT(0)
+
+#define FSPI_DLPR 0xB4
+
+#define FSPI_IPRXFCR 0xB8
+#define FSPI_IPRXFCR_CLR BIT(0)
+#define FSPI_IPRXFCR_DMA_EN BIT(1)
+#define FSPI_IPRXFCR_WMRK(x) ((x) << 2)
+
+#define FSPI_IPTXFCR 0xBC
+#define FSPI_IPTXFCR_CLR BIT(0)
+#define FSPI_IPTXFCR_DMA_EN BIT(1)
+#define FSPI_IPTXFCR_WMRK(x) ((x) << 2)
+
+#define FSPI_DLLACR 0xC0
+#define FSPI_DLLACR_OVRDEN BIT(8)
+
+#define FSPI_DLLBCR 0xC4
+#define FSPI_DLLBCR_OVRDEN BIT(8)
+
+#define FSPI_STS0 0xE0
+#define FSPI_STS0_DLPHB(x) ((x) << 8)
+#define FSPI_STS0_DLPHA(x) ((x) << 4)
+#define FSPI_STS0_CMD_SRC(x) ((x) << 2)
+#define FSPI_STS0_ARB_IDLE BIT(1)
+#define FSPI_STS0_SEQ_IDLE BIT(0)
+
+#define FSPI_STS1 0xE4
+#define FSPI_STS1_IP_ERRCD(x) ((x) << 24)
+#define FSPI_STS1_IP_ERRID(x) ((x) << 16)
+#define FSPI_STS1_AHB_ERRCD(x) ((x) << 8)
+#define FSPI_STS1_AHB_ERRID(x) (x)
+
+#define FSPI_AHBSPNST 0xEC
+#define FSPI_AHBSPNST_DATLFT(x) ((x) << 16)
+#define FSPI_AHBSPNST_BUFID(x) ((x) << 1)
+#define FSPI_AHBSPNST_ACTIVE BIT(0)
+
+#define FSPI_IPRXFSTS 0xF0
+#define FSPI_IPRXFSTS_RDCNTR(x) ((x) << 16)
+#define FSPI_IPRXFSTS_FILL(x) (x)
+
+#define FSPI_IPTXFSTS 0xF4
+#define FSPI_IPTXFSTS_WRCNTR(x) ((x) << 16)
+#define FSPI_IPTXFSTS_FILL(x) (x)
+
+#define FSPI_RFDR 0x100
+#define FSPI_TFDR 0x180
+
+#define FSPI_LUT_BASE 0x200
+#define FSPI_LUT_OFFSET (SEQID_LUT * 4 * 4)
+#define FSPI_LUT_REG(idx) \
+ (FSPI_LUT_BASE + FSPI_LUT_OFFSET + (idx) * 4)
+
+/* register map end */
+
+/* Instruction set for the LUT register. */
+#define LUT_STOP 0x00
+#define LUT_CMD 0x01
+#define LUT_ADDR 0x02
+#define LUT_CADDR_SDR 0x03
+#define LUT_MODE 0x04
+#define LUT_MODE2 0x05
+#define LUT_MODE4 0x06
+#define LUT_MODE8 0x07
+#define LUT_NXP_WRITE 0x08
+#define LUT_NXP_READ 0x09
+#define LUT_LEARN_SDR 0x0A
+#define LUT_DATSZ_SDR 0x0B
+#define LUT_DUMMY 0x0C
+#define LUT_DUMMY_RWDS_SDR 0x0D
+#define LUT_JMP_ON_CS 0x1F
+#define LUT_CMD_DDR 0x21
+#define LUT_ADDR_DDR 0x22
+#define LUT_CADDR_DDR 0x23
+#define LUT_MODE_DDR 0x24
+#define LUT_MODE2_DDR 0x25
+#define LUT_MODE4_DDR 0x26
+#define LUT_MODE8_DDR 0x27
+#define LUT_WRITE_DDR 0x28
+#define LUT_READ_DDR 0x29
+#define LUT_LEARN_DDR 0x2A
+#define LUT_DATSZ_DDR 0x2B
+#define LUT_DUMMY_DDR 0x2C
+#define LUT_DUMMY_RWDS_DDR 0x2D
+
+/*
+ * Calculate number of required PAD bits for LUT register.
+ *
+ * The pad stands for the number of IO lines [0:7].
+ * For example, the octal read needs eight IO lines,
+ * so you should use LUT_PAD(8). This macro
+ * returns 3 i.e. use eight (2^3) IP lines for read.
+ */
+#define LUT_PAD(x) (fls(x) - 1)
+
+/*
+ * Macro for constructing the LUT entries with the following
+ * register layout:
+ *
+ * ---------------------------------------------------
+ * | INSTR1 | PAD1 | OPRND1 | INSTR0 | PAD0 | OPRND0 |
+ * ---------------------------------------------------
+ */
+#define PAD_SHIFT 8
+#define INSTR_SHIFT 10
+#define OPRND_SHIFT 16
+
+/* Macros for constructing the LUT register. */
+#define LUT_DEF(idx, ins, pad, opr) \
+ ((((ins) << INSTR_SHIFT) | ((pad) << PAD_SHIFT) | \
+ (opr)) << (((idx) % 2) * OPRND_SHIFT))
+
+#define POLL_TOUT 5000
+#define NXP_FSPI_MAX_CHIPSELECT 4
+#define NXP_FSPI_MIN_IOMAP SZ_4M
+
+struct nxp_fspi_devtype_data {
+ unsigned int rxfifo;
+ unsigned int txfifo;
+ unsigned int ahb_buf_size;
+ unsigned int quirks;
+ bool little_endian;
+};
+
+static const struct nxp_fspi_devtype_data lx2160a_data = {
+ .rxfifo = SZ_512, /* (64 * 64 bits) */
+ .txfifo = SZ_1K, /* (128 * 64 bits) */
+ .ahb_buf_size = SZ_2K, /* (256 * 64 bits) */
+ .quirks = 0,
+ .little_endian = true, /* little-endian */
+};
+
+static const struct nxp_fspi_devtype_data imx8mm_data = {
+ .rxfifo = SZ_512, /* (64 * 64 bits) */
+ .txfifo = SZ_1K, /* (128 * 64 bits) */
+ .ahb_buf_size = SZ_2K, /* (256 * 64 bits) */
+ .quirks = 0,
+ .little_endian = true, /* little-endian */
+};
+
+static const struct nxp_fspi_devtype_data imx8qxp_data = {
+ .rxfifo = SZ_512, /* (64 * 64 bits) */
+ .txfifo = SZ_1K, /* (128 * 64 bits) */
+ .ahb_buf_size = SZ_2K, /* (256 * 64 bits) */
+ .quirks = 0,
+ .little_endian = true, /* little-endian */
+};
+
+struct nxp_fspi {
+ void __iomem *iobase;
+ void __iomem *ahb_addr;
+ u32 memmap_phy;
+ u32 memmap_phy_size;
+ u32 memmap_start;
+ u32 memmap_len;
+ struct clk *clk, *clk_en;
+ struct device *dev;
+ struct completion c;
+ const struct nxp_fspi_devtype_data *devtype_data;
+ struct mutex lock;
+ struct pm_qos_request pm_qos_req;
+ int selected;
+};
+
+/*
+ * R/W functions for big- or little-endian registers:
+ * The FSPI controller's endianness is independent of
+ * the CPU core's endianness. So far, although the CPU
+ * core is little-endian the FSPI controller can use
+ * big-endian or little-endian.
+ */
+static void fspi_writel(struct nxp_fspi *f, u32 val, void __iomem *addr)
+{
+ if (f->devtype_data->little_endian)
+ iowrite32(val, addr);
+ else
+ iowrite32be(val, addr);
+}
+
+static u32 fspi_readl(struct nxp_fspi *f, void __iomem *addr)
+{
+ if (f->devtype_data->little_endian)
+ return ioread32(addr);
+ else
+ return ioread32be(addr);
+}
+
+static irqreturn_t nxp_fspi_irq_handler(int irq, void *dev_id)
+{
+ struct nxp_fspi *f = dev_id;
+ u32 reg;
+
+ /* clear interrupt */
+ reg = fspi_readl(f, f->iobase + FSPI_INTR);
+ fspi_writel(f, FSPI_INTR_IPCMDDONE, f->iobase + FSPI_INTR);
+
+ if (reg & FSPI_INTR_IPCMDDONE)
+ complete(&f->c);
+
+ return IRQ_HANDLED;
+}
+
+static int nxp_fspi_check_buswidth(struct nxp_fspi *f, u8 width)
+{
+ switch (width) {
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ return 0;
+ }
+
+ return -ENOTSUPP;
+}
+
+static bool nxp_fspi_supports_op(struct spi_mem *mem,
+ const struct spi_mem_op *op)
+{
+ struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
+ int ret;
+
+ ret = nxp_fspi_check_buswidth(f, op->cmd.buswidth);
+
+ if (op->addr.nbytes)
+ ret |= nxp_fspi_check_buswidth(f, op->addr.buswidth);
+
+ if (op->dummy.nbytes)
+ ret |= nxp_fspi_check_buswidth(f, op->dummy.buswidth);
+
+ if (op->data.nbytes)
+ ret |= nxp_fspi_check_buswidth(f, op->data.buswidth);
+
+ if (ret)
+ return false;
+
+ /*
+ * The number of address bytes should be equal to or less than 4 bytes.
+ */
+ if (op->addr.nbytes > 4)
+ return false;
+
+ /*
+ * If requested address value is greater than controller assigned
+ * memory mapped space, return error as it didn't fit in the range
+ * of assigned address space.
+ */
+ if (op->addr.val >= f->memmap_phy_size)
+ return false;
+
+ /* Max 64 dummy clock cycles supported */
+ if (op->dummy.buswidth &&
+ (op->dummy.nbytes * 8 / op->dummy.buswidth > 64))
+ return false;
+
+ /* Max data length, check controller limits and alignment */
+ if (op->data.dir == SPI_MEM_DATA_IN &&
+ (op->data.nbytes > f->devtype_data->ahb_buf_size ||
+ (op->data.nbytes > f->devtype_data->rxfifo - 4 &&
+ !IS_ALIGNED(op->data.nbytes, 8))))
+ return false;
+
+ if (op->data.dir == SPI_MEM_DATA_OUT &&
+ op->data.nbytes > f->devtype_data->txfifo)
+ return false;
+
+ return spi_mem_default_supports_op(mem, op);
+}
+
+/* Instead of busy looping invoke readl_poll_timeout functionality. */
+static int fspi_readl_poll_tout(struct nxp_fspi *f, void __iomem *base,
+ u32 mask, u32 delay_us,
+ u32 timeout_us, bool c)
+{
+ u32 reg;
+
+ if (!f->devtype_data->little_endian)
+ mask = (u32)cpu_to_be32(mask);
+
+ if (c)
+ return readl_poll_timeout(base, reg, (reg & mask),
+ delay_us, timeout_us);
+ else
+ return readl_poll_timeout(base, reg, !(reg & mask),
+ delay_us, timeout_us);
+}
+
+/*
+ * If the slave device content being changed by Write/Erase, need to
+ * invalidate the AHB buffer. This can be achieved by doing the reset
+ * of controller after setting MCR0[SWRESET] bit.
+ */
+static inline void nxp_fspi_invalid(struct nxp_fspi *f)
+{
+ u32 reg;
+ int ret;
+
+ reg = fspi_readl(f, f->iobase + FSPI_MCR0);
+ fspi_writel(f, reg | FSPI_MCR0_SWRST, f->iobase + FSPI_MCR0);
+
+ /* w1c register, wait unit clear */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_MCR0,
+ FSPI_MCR0_SWRST, 0, POLL_TOUT, false);
+ WARN_ON(ret);
+}
+
+static void nxp_fspi_prepare_lut(struct nxp_fspi *f,
+ const struct spi_mem_op *op)
+{
+ void __iomem *base = f->iobase;
+ u32 lutval[4] = {};
+ int lutidx = 1, i;
+
+ /* cmd */
+ lutval[0] |= LUT_DEF(0, LUT_CMD, LUT_PAD(op->cmd.buswidth),
+ op->cmd.opcode);
+
+ /* addr bytes */
+ if (op->addr.nbytes) {
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_ADDR,
+ LUT_PAD(op->addr.buswidth),
+ op->addr.nbytes * 8);
+ lutidx++;
+ }
+
+ /* dummy bytes, if needed */
+ if (op->dummy.nbytes) {
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_DUMMY,
+ /*
+ * Due to FlexSPI controller limitation number of PAD for dummy
+ * buswidth needs to be programmed as equal to data buswidth.
+ */
+ LUT_PAD(op->data.buswidth),
+ op->dummy.nbytes * 8 /
+ op->dummy.buswidth);
+ lutidx++;
+ }
+
+ /* read/write data bytes */
+ if (op->data.nbytes) {
+ lutval[lutidx / 2] |= LUT_DEF(lutidx,
+ op->data.dir == SPI_MEM_DATA_IN ?
+ LUT_NXP_READ : LUT_NXP_WRITE,
+ LUT_PAD(op->data.buswidth),
+ 0);
+ lutidx++;
+ }
+
+ /* stop condition. */
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_STOP, 0, 0);
+
+ /* unlock LUT */
+ fspi_writel(f, FSPI_LUTKEY_VALUE, f->iobase + FSPI_LUTKEY);
+ fspi_writel(f, FSPI_LCKER_UNLOCK, f->iobase + FSPI_LCKCR);
+
+ /* fill LUT */
+ for (i = 0; i < ARRAY_SIZE(lutval); i++)
+ fspi_writel(f, lutval[i], base + FSPI_LUT_REG(i));
+
+ dev_dbg(f->dev, "CMD[%x] lutval[0:%x \t 1:%x \t 2:%x \t 3:%x]\n",
+ op->cmd.opcode, lutval[0], lutval[1], lutval[2], lutval[3]);
+
+ /* lock LUT */
+ fspi_writel(f, FSPI_LUTKEY_VALUE, f->iobase + FSPI_LUTKEY);
+ fspi_writel(f, FSPI_LCKER_LOCK, f->iobase + FSPI_LCKCR);
+}
+
+static int nxp_fspi_clk_prep_enable(struct nxp_fspi *f)
+{
+ int ret;
+
+ if (is_acpi_node(f->dev->fwnode))
+ return 0;
+
+ ret = clk_prepare_enable(f->clk_en);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(f->clk);
+ if (ret) {
+ clk_disable_unprepare(f->clk_en);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int nxp_fspi_clk_disable_unprep(struct nxp_fspi *f)
+{
+ if (is_acpi_node(f->dev->fwnode))
+ return 0;
+
+ clk_disable_unprepare(f->clk);
+ clk_disable_unprepare(f->clk_en);
+
+ return 0;
+}
+
+/*
+ * In FlexSPI controller, flash access is based on value of FSPI_FLSHXXCR0
+ * register and start base address of the slave device.
+ *
+ * (Higher address)
+ * -------- <-- FLSHB2CR0
+ * | B2 |
+ * | |
+ * B2 start address --> -------- <-- FLSHB1CR0
+ * | B1 |
+ * | |
+ * B1 start address --> -------- <-- FLSHA2CR0
+ * | A2 |
+ * | |
+ * A2 start address --> -------- <-- FLSHA1CR0
+ * | A1 |
+ * | |
+ * A1 start address --> -------- (Lower address)
+ *
+ *
+ * Start base address defines the starting address range for given CS and
+ * FSPI_FLSHXXCR0 defines the size of the slave device connected at given CS.
+ *
+ * But, different targets are having different combinations of number of CS,
+ * some targets only have single CS or two CS covering controller's full
+ * memory mapped space area.
+ * Thus, implementation is being done as independent of the size and number
+ * of the connected slave device.
+ * Assign controller memory mapped space size as the size to the connected
+ * slave device.
+ * Mark FLSHxxCR0 as zero initially and then assign value only to the selected
+ * chip-select Flash configuration register.
+ *
+ * For e.g. to access CS2 (B1), FLSHB1CR0 register would be equal to the
+ * memory mapped size of the controller.
+ * Value for rest of the CS FLSHxxCR0 register would be zero.
+ *
+ */
+static void nxp_fspi_select_mem(struct nxp_fspi *f, struct spi_device *spi)
+{
+ unsigned long rate = spi->max_speed_hz;
+ int ret;
+ uint64_t size_kb;
+
+ /*
+ * Return, if previously selected slave device is same as current
+ * requested slave device.
+ */
+ if (f->selected == spi->chip_select)
+ return;
+
+ /* Reset FLSHxxCR0 registers */
+ fspi_writel(f, 0, f->iobase + FSPI_FLSHA1CR0);
+ fspi_writel(f, 0, f->iobase + FSPI_FLSHA2CR0);
+ fspi_writel(f, 0, f->iobase + FSPI_FLSHB1CR0);
+ fspi_writel(f, 0, f->iobase + FSPI_FLSHB2CR0);
+
+ /* Assign controller memory mapped space as size, KBytes, of flash. */
+ size_kb = FSPI_FLSHXCR0_SZ(f->memmap_phy_size);
+
+ fspi_writel(f, size_kb, f->iobase + FSPI_FLSHA1CR0 +
+ 4 * spi->chip_select);
+
+ dev_dbg(f->dev, "Slave device [CS:%x] selected\n", spi->chip_select);
+
+ nxp_fspi_clk_disable_unprep(f);
+
+ ret = clk_set_rate(f->clk, rate);
+ if (ret)
+ return;
+
+ ret = nxp_fspi_clk_prep_enable(f);
+ if (ret)
+ return;
+
+ f->selected = spi->chip_select;
+}
+
+static int nxp_fspi_read_ahb(struct nxp_fspi *f, const struct spi_mem_op *op)
+{
+ u32 start = op->addr.val;
+ u32 len = op->data.nbytes;
+
+ /* if necessary, ioremap before AHB read */
+ if ((!f->ahb_addr) || start < f->memmap_start ||
+ start + len > f->memmap_start + f->memmap_len) {
+ if (f->ahb_addr)
+ iounmap(f->ahb_addr);
+
+ f->memmap_start = start;
+ f->memmap_len = len > NXP_FSPI_MIN_IOMAP ?
+ len : NXP_FSPI_MIN_IOMAP;
+
+ f->ahb_addr = ioremap(f->memmap_phy + f->memmap_start,
+ f->memmap_len);
+
+ if (!f->ahb_addr) {
+ dev_err(f->dev, "failed to alloc memory\n");
+ return -ENOMEM;
+ }
+ }
+
+ /* Read out the data directly from the AHB buffer. */
+ memcpy_fromio(op->data.buf.in,
+ f->ahb_addr + start - f->memmap_start, len);
+
+ return 0;
+}
+
+static void nxp_fspi_fill_txfifo(struct nxp_fspi *f,
+ const struct spi_mem_op *op)
+{
+ void __iomem *base = f->iobase;
+ int i, ret;
+ u8 *buf = (u8 *) op->data.buf.out;
+
+ /* clear the TX FIFO. */
+ fspi_writel(f, FSPI_IPTXFCR_CLR, base + FSPI_IPTXFCR);
+
+ /*
+ * Default value of water mark level is 8 bytes, hence in single
+ * write request controller can write max 8 bytes of data.
+ */
+
+ for (i = 0; i < ALIGN_DOWN(op->data.nbytes, 8); i += 8) {
+ /* Wait for TXFIFO empty */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
+ FSPI_INTR_IPTXWE, 0,
+ POLL_TOUT, true);
+ WARN_ON(ret);
+
+ fspi_writel(f, *(u32 *) (buf + i), base + FSPI_TFDR);
+ fspi_writel(f, *(u32 *) (buf + i + 4), base + FSPI_TFDR + 4);
+ fspi_writel(f, FSPI_INTR_IPTXWE, base + FSPI_INTR);
+ }
+
+ if (i < op->data.nbytes) {
+ u32 data = 0;
+ int j;
+ /* Wait for TXFIFO empty */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
+ FSPI_INTR_IPTXWE, 0,
+ POLL_TOUT, true);
+ WARN_ON(ret);
+
+ for (j = 0; j < ALIGN(op->data.nbytes - i, 4); j += 4) {
+ memcpy(&data, buf + i + j, 4);
+ fspi_writel(f, data, base + FSPI_TFDR + j);
+ }
+ fspi_writel(f, FSPI_INTR_IPTXWE, base + FSPI_INTR);
+ }
+}
+
+static void nxp_fspi_read_rxfifo(struct nxp_fspi *f,
+ const struct spi_mem_op *op)
+{
+ void __iomem *base = f->iobase;
+ int i, ret;
+ int len = op->data.nbytes;
+ u8 *buf = (u8 *) op->data.buf.in;
+
+ /*
+ * Default value of water mark level is 8 bytes, hence in single
+ * read request controller can read max 8 bytes of data.
+ */
+ for (i = 0; i < ALIGN_DOWN(len, 8); i += 8) {
+ /* Wait for RXFIFO available */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
+ FSPI_INTR_IPRXWA, 0,
+ POLL_TOUT, true);
+ WARN_ON(ret);
+
+ *(u32 *)(buf + i) = fspi_readl(f, base + FSPI_RFDR);
+ *(u32 *)(buf + i + 4) = fspi_readl(f, base + FSPI_RFDR + 4);
+ /* move the FIFO pointer */
+ fspi_writel(f, FSPI_INTR_IPRXWA, base + FSPI_INTR);
+ }
+
+ if (i < len) {
+ u32 tmp;
+ int size, j;
+
+ buf = op->data.buf.in + i;
+ /* Wait for RXFIFO available */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
+ FSPI_INTR_IPRXWA, 0,
+ POLL_TOUT, true);
+ WARN_ON(ret);
+
+ len = op->data.nbytes - i;
+ for (j = 0; j < op->data.nbytes - i; j += 4) {
+ tmp = fspi_readl(f, base + FSPI_RFDR + j);
+ size = min(len, 4);
+ memcpy(buf + j, &tmp, size);
+ len -= size;
+ }
+ }
+
+ /* invalid the RXFIFO */
+ fspi_writel(f, FSPI_IPRXFCR_CLR, base + FSPI_IPRXFCR);
+ /* move the FIFO pointer */
+ fspi_writel(f, FSPI_INTR_IPRXWA, base + FSPI_INTR);
+}
+
+static int nxp_fspi_do_op(struct nxp_fspi *f, const struct spi_mem_op *op)
+{
+ void __iomem *base = f->iobase;
+ int seqnum = 0;
+ int err = 0;
+ u32 reg;
+
+ reg = fspi_readl(f, base + FSPI_IPRXFCR);
+ /* invalid RXFIFO first */
+ reg &= ~FSPI_IPRXFCR_DMA_EN;
+ reg = reg | FSPI_IPRXFCR_CLR;
+ fspi_writel(f, reg, base + FSPI_IPRXFCR);
+
+ init_completion(&f->c);
+
+ fspi_writel(f, op->addr.val, base + FSPI_IPCR0);
+ /*
+ * Always start the sequence at the same index since we update
+ * the LUT at each exec_op() call. And also specify the DATA
+ * length, since it's has not been specified in the LUT.
+ */
+ fspi_writel(f, op->data.nbytes |
+ (SEQID_LUT << FSPI_IPCR1_SEQID_SHIFT) |
+ (seqnum << FSPI_IPCR1_SEQNUM_SHIFT),
+ base + FSPI_IPCR1);
+
+ /* Trigger the LUT now. */
+ fspi_writel(f, FSPI_IPCMD_TRG, base + FSPI_IPCMD);
+
+ /* Wait for the interrupt. */
+ if (!wait_for_completion_timeout(&f->c, msecs_to_jiffies(1000)))
+ err = -ETIMEDOUT;
+
+ /* Invoke IP data read, if request is of data read. */
+ if (!err && op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN)
+ nxp_fspi_read_rxfifo(f, op);
+
+ return err;
+}
+
+static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+ struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
+ int err = 0;
+
+ mutex_lock(&f->lock);
+
+ /* Wait for controller being ready. */
+ err = fspi_readl_poll_tout(f, f->iobase + FSPI_STS0,
+ FSPI_STS0_ARB_IDLE, 1, POLL_TOUT, true);
+ WARN_ON(err);
+
+ nxp_fspi_select_mem(f, mem->spi);
+
+ nxp_fspi_prepare_lut(f, op);
+ /*
+ * If we have large chunks of data, we read them through the AHB bus
+ * by accessing the mapped memory. In all other cases we use
+ * IP commands to access the flash.
+ */
+ if (op->data.nbytes > (f->devtype_data->rxfifo - 4) &&
+ op->data.dir == SPI_MEM_DATA_IN) {
+ err = nxp_fspi_read_ahb(f, op);
+ } else {
+ if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
+ nxp_fspi_fill_txfifo(f, op);
+
+ err = nxp_fspi_do_op(f, op);
+ }
+
+ /* Invalidate the data in the AHB buffer. */
+ nxp_fspi_invalid(f);
+
+ mutex_unlock(&f->lock);
+
+ return err;
+}
+
+static int nxp_fspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+ struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
+
+ if (op->data.dir == SPI_MEM_DATA_OUT) {
+ if (op->data.nbytes > f->devtype_data->txfifo)
+ op->data.nbytes = f->devtype_data->txfifo;
+ } else {
+ if (op->data.nbytes > f->devtype_data->ahb_buf_size)
+ op->data.nbytes = f->devtype_data->ahb_buf_size;
+ else if (op->data.nbytes > (f->devtype_data->rxfifo - 4))
+ op->data.nbytes = ALIGN_DOWN(op->data.nbytes, 8);
+ }
+
+ return 0;
+}
+
+static int nxp_fspi_default_setup(struct nxp_fspi *f)
+{
+ void __iomem *base = f->iobase;
+ int ret, i;
+ u32 reg;
+
+ /* disable and unprepare clock to avoid glitch pass to controller */
+ nxp_fspi_clk_disable_unprep(f);
+
+ /* the default frequency, we will change it later if necessary. */
+ ret = clk_set_rate(f->clk, 20000000);
+ if (ret)
+ return ret;
+
+ ret = nxp_fspi_clk_prep_enable(f);
+ if (ret)
+ return ret;
+
+ /* Reset the module */
+ /* w1c register, wait unit clear */
+ ret = fspi_readl_poll_tout(f, f->iobase + FSPI_MCR0,
+ FSPI_MCR0_SWRST, 0, POLL_TOUT, false);
+ WARN_ON(ret);
+
+ /* Disable the module */
+ fspi_writel(f, FSPI_MCR0_MDIS, base + FSPI_MCR0);
+
+ /* Reset the DLL register to default value */
+ fspi_writel(f, FSPI_DLLACR_OVRDEN, base + FSPI_DLLACR);
+ fspi_writel(f, FSPI_DLLBCR_OVRDEN, base + FSPI_DLLBCR);
+
+ /* enable module */
+ fspi_writel(f, FSPI_MCR0_AHB_TIMEOUT(0xFF) |
+ FSPI_MCR0_IP_TIMEOUT(0xFF) | (u32) FSPI_MCR0_OCTCOMB_EN,
+ base + FSPI_MCR0);
+
+ /*
+ * Disable same device enable bit and configure all slave devices
+ * independently.
+ */
+ reg = fspi_readl(f, f->iobase + FSPI_MCR2);
+ reg = reg & ~(FSPI_MCR2_SAMEDEVICEEN);
+ fspi_writel(f, reg, base + FSPI_MCR2);
+
+ /* AHB configuration for access buffer 0~7. */
+ for (i = 0; i < 7; i++)
+ fspi_writel(f, 0, base + FSPI_AHBRX_BUF0CR0 + 4 * i);
+
+ /*
+ * Set ADATSZ with the maximum AHB buffer size to improve the read
+ * performance.
+ */
+ fspi_writel(f, (f->devtype_data->ahb_buf_size / 8 |
+ FSPI_AHBRXBUF0CR7_PREF), base + FSPI_AHBRX_BUF7CR0);
+
+ /* prefetch and no start address alignment limitation */
+ fspi_writel(f, FSPI_AHBCR_PREF_EN | FSPI_AHBCR_RDADDROPT,
+ base + FSPI_AHBCR);
+
+ /* Reset the FLSHxCR1 registers. */
+ reg = FSPI_FLSHXCR1_TCSH(0x3) | FSPI_FLSHXCR1_TCSS(0x3);
+ fspi_writel(f, reg, base + FSPI_FLSHA1CR1);
+ fspi_writel(f, reg, base + FSPI_FLSHA2CR1);
+ fspi_writel(f, reg, base + FSPI_FLSHB1CR1);
+ fspi_writel(f, reg, base + FSPI_FLSHB2CR1);
+
+ /* AHB Read - Set lut sequence ID for all CS. */
+ fspi_writel(f, SEQID_LUT, base + FSPI_FLSHA1CR2);
+ fspi_writel(f, SEQID_LUT, base + FSPI_FLSHA2CR2);
+ fspi_writel(f, SEQID_LUT, base + FSPI_FLSHB1CR2);
+ fspi_writel(f, SEQID_LUT, base + FSPI_FLSHB2CR2);
+
+ f->selected = -1;
+
+ /* enable the interrupt */
+ fspi_writel(f, FSPI_INTEN_IPCMDDONE, base + FSPI_INTEN);
+
+ return 0;
+}
+
+static const char *nxp_fspi_get_name(struct spi_mem *mem)
+{
+ struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
+ struct device *dev = &mem->spi->dev;
+ const char *name;
+
+ // Set custom name derived from the platform_device of the controller.
+ if (of_get_available_child_count(f->dev->of_node) == 1)
+ return dev_name(f->dev);
+
+ name = devm_kasprintf(dev, GFP_KERNEL,
+ "%s-%d", dev_name(f->dev),
+ mem->spi->chip_select);
+
+ if (!name) {
+ dev_err(dev, "failed to get memory for custom flash name\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return name;
+}
+
+static const struct spi_controller_mem_ops nxp_fspi_mem_ops = {
+ .adjust_op_size = nxp_fspi_adjust_op_size,
+ .supports_op = nxp_fspi_supports_op,
+ .exec_op = nxp_fspi_exec_op,
+ .get_name = nxp_fspi_get_name,
+};
+
+static int nxp_fspi_probe(struct platform_device *pdev)
+{
+ struct spi_controller *ctlr;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct resource *res;
+ struct nxp_fspi *f;
+ int ret;
+ u32 reg;
+
+ ctlr = spi_alloc_master(&pdev->dev, sizeof(*f));
+ if (!ctlr)
+ return -ENOMEM;
+
+ ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL |
+ SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL;
+
+ f = spi_controller_get_devdata(ctlr);
+ f->dev = dev;
+ f->devtype_data = device_get_match_data(dev);
+ if (!f->devtype_data) {
+ ret = -ENODEV;
+ goto err_put_ctrl;
+ }
+
+ platform_set_drvdata(pdev, f);
+
+ /* find the resources - configuration register address space */
+ if (is_acpi_node(f->dev->fwnode))
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ else
+ res = platform_get_resource_byname(pdev,
+ IORESOURCE_MEM, "fspi_base");
+
+ f->iobase = devm_ioremap_resource(dev, res);
+ if (IS_ERR(f->iobase)) {
+ ret = PTR_ERR(f->iobase);
+ goto err_put_ctrl;
+ }
+
+ /* find the resources - controller memory mapped space */
+ if (is_acpi_node(f->dev->fwnode))
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ else
+ res = platform_get_resource_byname(pdev,
+ IORESOURCE_MEM, "fspi_mmap");
+
+ if (!res) {
+ ret = -ENODEV;
+ goto err_put_ctrl;
+ }
+
+ /* assign memory mapped starting address and mapped size. */
+ f->memmap_phy = res->start;
+ f->memmap_phy_size = resource_size(res);
+
+ /* find the clocks */
+ if (dev_of_node(&pdev->dev)) {
+ f->clk_en = devm_clk_get(dev, "fspi_en");
+ if (IS_ERR(f->clk_en)) {
+ ret = PTR_ERR(f->clk_en);
+ goto err_put_ctrl;
+ }
+
+ f->clk = devm_clk_get(dev, "fspi");
+ if (IS_ERR(f->clk)) {
+ ret = PTR_ERR(f->clk);
+ goto err_put_ctrl;
+ }
+
+ ret = nxp_fspi_clk_prep_enable(f);
+ if (ret) {
+ dev_err(dev, "can not enable the clock\n");
+ goto err_put_ctrl;
+ }
+ }
+
+ /* Clear potential interrupts */
+ reg = fspi_readl(f, f->iobase + FSPI_INTR);
+ if (reg)
+ fspi_writel(f, reg, f->iobase + FSPI_INTR);
+
+ /* find the irq */
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ goto err_disable_clk;
+
+ ret = devm_request_irq(dev, ret,
+ nxp_fspi_irq_handler, 0, pdev->name, f);
+ if (ret) {
+ dev_err(dev, "failed to request irq: %d\n", ret);
+ goto err_disable_clk;
+ }
+
+ mutex_init(&f->lock);
+
+ ctlr->bus_num = -1;
+ ctlr->num_chipselect = NXP_FSPI_MAX_CHIPSELECT;
+ ctlr->mem_ops = &nxp_fspi_mem_ops;
+
+ nxp_fspi_default_setup(f);
+
+ ctlr->dev.of_node = np;
+
+ ret = devm_spi_register_controller(&pdev->dev, ctlr);
+ if (ret)
+ goto err_destroy_mutex;
+
+ return 0;
+
+err_destroy_mutex:
+ mutex_destroy(&f->lock);
+
+err_disable_clk:
+ nxp_fspi_clk_disable_unprep(f);
+
+err_put_ctrl:
+ spi_controller_put(ctlr);
+
+ dev_err(dev, "NXP FSPI probe failed\n");
+ return ret;
+}
+
+static int nxp_fspi_remove(struct platform_device *pdev)
+{
+ struct nxp_fspi *f = platform_get_drvdata(pdev);
+
+ /* disable the hardware */
+ fspi_writel(f, FSPI_MCR0_MDIS, f->iobase + FSPI_MCR0);
+
+ nxp_fspi_clk_disable_unprep(f);
+
+ mutex_destroy(&f->lock);
+
+ if (f->ahb_addr)
+ iounmap(f->ahb_addr);
+
+ return 0;
+}
+
+static int nxp_fspi_suspend(struct device *dev)
+{
+ return 0;
+}
+
+static int nxp_fspi_resume(struct device *dev)
+{
+ struct nxp_fspi *f = dev_get_drvdata(dev);
+
+ nxp_fspi_default_setup(f);
+
+ return 0;
+}
+
+static const struct of_device_id nxp_fspi_dt_ids[] = {
+ { .compatible = "nxp,lx2160a-fspi", .data = (void *)&lx2160a_data, },
+ { .compatible = "nxp,imx8mm-fspi", .data = (void *)&imx8mm_data, },
+ { .compatible = "nxp,imx8qxp-fspi", .data = (void *)&imx8qxp_data, },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, nxp_fspi_dt_ids);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id nxp_fspi_acpi_ids[] = {
+ { "NXP0009", .driver_data = (kernel_ulong_t)&lx2160a_data, },
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, nxp_fspi_acpi_ids);
+#endif
+
+static const struct dev_pm_ops nxp_fspi_pm_ops = {
+ .suspend = nxp_fspi_suspend,
+ .resume = nxp_fspi_resume,
+};
+
+static struct platform_driver nxp_fspi_driver = {
+ .driver = {
+ .name = "nxp-fspi",
+ .of_match_table = nxp_fspi_dt_ids,
+ .acpi_match_table = ACPI_PTR(nxp_fspi_acpi_ids),
+ .pm = &nxp_fspi_pm_ops,
+ },
+ .probe = nxp_fspi_probe,
+ .remove = nxp_fspi_remove,
+};
+module_platform_driver(nxp_fspi_driver);
+
+MODULE_DESCRIPTION("NXP FSPI Controller Driver");
+MODULE_AUTHOR("NXP Semiconductor");
+MODULE_AUTHOR("Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>");
+MODULE_AUTHOR("Boris Brezillon <bbrezillon@kernel.org>");
+MODULE_AUTHOR("Frieder Schrempf <frieder.schrempf@kontron.de>");
+MODULE_LICENSE("GPL v2");