diff options
| -rw-r--r-- | Documentation/mtd/intel-spi.txt | 88 | ||||
| -rw-r--r-- | drivers/mtd/spi-nor/Kconfig | 20 | ||||
| -rw-r--r-- | drivers/mtd/spi-nor/Makefile | 2 | ||||
| -rw-r--r-- | drivers/mtd/spi-nor/intel-spi-platform.c | 57 | ||||
| -rw-r--r-- | drivers/mtd/spi-nor/intel-spi.c | 777 | ||||
| -rw-r--r-- | drivers/mtd/spi-nor/intel-spi.h | 24 | ||||
| -rw-r--r-- | include/linux/platform_data/intel-spi.h | 31 |
7 files changed, 999 insertions, 0 deletions
diff --git a/Documentation/mtd/intel-spi.txt b/Documentation/mtd/intel-spi.txt new file mode 100644 index 000000000000..bc357729c2cb --- /dev/null +++ b/Documentation/mtd/intel-spi.txt @@ -0,0 +1,88 @@ +Upgrading BIOS using intel-spi +------------------------------ + +Many Intel CPUs like Baytrail and Braswell include SPI serial flash host +controller which is used to hold BIOS and other platform specific data. +Since contents of the SPI serial flash is crucial for machine to function, +it is typically protected by different hardware protection mechanisms to +avoid accidental (or on purpose) overwrite of the content. + +Not all manufacturers protect the SPI serial flash, mainly because it +allows upgrading the BIOS image directly from an OS. + +The intel-spi driver makes it possible to read and write the SPI serial +flash, if certain protection bits are not set and locked. If it finds +any of them set, the whole MTD device is made read-only to prevent +partial overwrites. By default the driver exposes SPI serial flash +contents as read-only but it can be changed from kernel command line, +passing "intel-spi.writeable=1". + +Please keep in mind that overwriting the BIOS image on SPI serial flash +might render the machine unbootable and requires special equipment like +Dediprog to revive. You have been warned! + +Below are the steps how to upgrade MinnowBoard MAX BIOS directly from +Linux. + + 1) Download and extract the latest Minnowboard MAX BIOS SPI image + [1]. At the time writing this the latest image is v92. + + 2) Install mtd-utils package [2]. We need this in order to erase the SPI + serial flash. Distros like Debian and Fedora have this prepackaged with + name "mtd-utils". + + 3) Add "intel-spi.writeable=1" to the kernel command line and reboot + the board (you can also reload the driver passing "writeable=1" as + module parameter to modprobe). + + 4) Once the board is up and running again, find the right MTD partition + (it is named as "BIOS"): + + # cat /proc/mtd + dev: size erasesize name + mtd0: 00800000 00001000 "BIOS" + + So here it will be /dev/mtd0 but it may vary. + + 5) Make backup of the existing image first: + + # dd if=/dev/mtd0ro of=bios.bak + 16384+0 records in + 16384+0 records out + 8388608 bytes (8.4 MB) copied, 10.0269 s, 837 kB/s + + 6) Verify the backup + + # sha1sum /dev/mtd0ro bios.bak + fdbb011920572ca6c991377c4b418a0502668b73 /dev/mtd0ro + fdbb011920572ca6c991377c4b418a0502668b73 bios.bak + + The SHA1 sums must match. Otherwise do not continue any further! + + 7) Erase the SPI serial flash. After this step, do not reboot the + board! Otherwise it will not start anymore. + + # flash_erase /dev/mtd0 0 0 + Erasing 4 Kibyte @ 7ff000 -- 100 % complete + + 8) Once completed without errors you can write the new BIOS image: + + # dd if=MNW2MAX1.X64.0092.R01.1605221712.bin of=/dev/mtd0 + + 9) Verify that the new content of the SPI serial flash matches the new + BIOS image: + + # sha1sum /dev/mtd0ro MNW2MAX1.X64.0092.R01.1605221712.bin + 9b4df9e4be2057fceec3a5529ec3d950836c87a2 /dev/mtd0ro + 9b4df9e4be2057fceec3a5529ec3d950836c87a2 MNW2MAX1.X64.0092.R01.1605221712.bin + + The SHA1 sums should match. + + 10) Now you can reboot your board and observe the new BIOS starting up + properly. + +References +---------- + +[1] https://firmware.intel.com/sites/default/files/MinnowBoard.MAX_.X64.92.R01.zip +[2] http://www.linux-mtd.infradead.org/ diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig index 4a682ee0f632..02013ffa5231 100644 --- a/drivers/mtd/spi-nor/Kconfig +++ b/drivers/mtd/spi-nor/Kconfig @@ -76,4 +76,24 @@ config SPI_NXP_SPIFI Flash. Enable this option if you have a device with a SPIFI controller and want to access the Flash as a mtd device. +config SPI_INTEL_SPI + tristate + +config SPI_INTEL_SPI_PLATFORM + tristate "Intel PCH/PCU SPI flash platform driver" if EXPERT + depends on X86 + select SPI_INTEL_SPI + help + This enables platform support for the Intel PCH/PCU SPI + controller in master mode. This controller is present in modern + Intel hardware and is used to hold BIOS and other persistent + settings. Using this driver it is possible to upgrade BIOS + directly from Linux. + + Say N here unless you know what you are doing. Overwriting the + SPI flash may render the system unbootable. + + To compile this driver as a module, choose M here: the module + will be called intel-spi-platform. + endif # MTD_SPI_NOR diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile index 121695e83542..1796e8cd6e1a 100644 --- a/drivers/mtd/spi-nor/Makefile +++ b/drivers/mtd/spi-nor/Makefile @@ -5,3 +5,5 @@ obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o obj-$(CONFIG_SPI_HISI_SFC) += hisi-sfc.o obj-$(CONFIG_MTD_MT81xx_NOR) += mtk-quadspi.o obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o +obj-$(CONFIG_SPI_INTEL_SPI) += intel-spi.o +obj-$(CONFIG_SPI_INTEL_SPI_PLATFORM) += intel-spi-platform.o diff --git a/drivers/mtd/spi-nor/intel-spi-platform.c b/drivers/mtd/spi-nor/intel-spi-platform.c new file mode 100644 index 000000000000..5c943df9398f --- /dev/null +++ b/drivers/mtd/spi-nor/intel-spi-platform.c @@ -0,0 +1,57 @@ +/* + * Intel PCH/PCU SPI flash platform driver. + * + * Copyright (C) 2016, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * 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. + */ + +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#include "intel-spi.h" + +static int intel_spi_platform_probe(struct platform_device *pdev) +{ + struct intel_spi_boardinfo *info; + struct intel_spi *ispi; + struct resource *mem; + + info = dev_get_platdata(&pdev->dev); + if (!info) + return -EINVAL; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ispi = intel_spi_probe(&pdev->dev, mem, info); + if (IS_ERR(ispi)) + return PTR_ERR(ispi); + + platform_set_drvdata(pdev, ispi); + return 0; +} + +static int intel_spi_platform_remove(struct platform_device *pdev) +{ + struct intel_spi *ispi = platform_get_drvdata(pdev); + + return intel_spi_remove(ispi); +} + +static struct platform_driver intel_spi_platform_driver = { + .probe = intel_spi_platform_probe, + .remove = intel_spi_platform_remove, + .driver = { + .name = "intel-spi", + }, +}; + +module_platform_driver(intel_spi_platform_driver); + +MODULE_DESCRIPTION("Intel PCH/PCU SPI flash platform driver"); +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:intel-spi"); diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c new file mode 100644 index 000000000000..a10f6027b386 --- /dev/null +++ b/drivers/mtd/spi-nor/intel-spi.c @@ -0,0 +1,777 @@ +/* + * Intel PCH/PCU SPI flash driver. + * + * Copyright (C) 2016, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * 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. + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/sizes.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/spi-nor.h> +#include <linux/platform_data/intel-spi.h> + +#include "intel-spi.h" + +/* Offsets are from @ispi->base */ +#define BFPREG 0x00 + +#define HSFSTS_CTL 0x04 +#define HSFSTS_CTL_FSMIE BIT(31) +#define HSFSTS_CTL_FDBC_SHIFT 24 +#define HSFSTS_CTL_FDBC_MASK (0x3f << HSFSTS_CTL_FDBC_SHIFT) + +#define HSFSTS_CTL_FCYCLE_SHIFT 17 +#define HSFSTS_CTL_FCYCLE_MASK (0x0f << HSFSTS_CTL_FCYCLE_SHIFT) +/* HW sequencer opcodes */ +#define HSFSTS_CTL_FCYCLE_READ (0x00 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_WRITE (0x02 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_ERASE (0x03 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_ERASE_64K (0x04 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_RDID (0x06 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_WRSR (0x07 << HSFSTS_CTL_FCYCLE_SHIFT) +#define HSFSTS_CTL_FCYCLE_RDSR (0x08 << HSFSTS_CTL_FCYCLE_SHIFT) + +#define HSFSTS_CTL_FGO BIT(16) +#define HSFSTS_CTL_FLOCKDN BIT(15) +#define HSFSTS_CTL_FDV BIT(14) +#define HSFSTS_CTL_SCIP BIT(5) +#define HSFSTS_CTL_AEL BIT(2) +#define HSFSTS_CTL_FCERR BIT(1) +#define HSFSTS_CTL_FDONE BIT(0) + +#define FADDR 0x08 +#define DLOCK 0x0c +#define FDATA(n) (0x10 + ((n) * 4)) + +#define FRACC 0x50 + +#define FREG(n) (0x54 + ((n) * 4)) +#define FREG_BASE_MASK 0x3fff +#define FREG_LIMIT_SHIFT 16 +#define FREG_LIMIT_MASK (0x03fff << FREG_LIMIT_SHIFT) + +/* Offset is from @ispi->pregs */ +#define PR(n) ((n) * 4) +#define PR_WPE BIT(31) +#define PR_LIMIT_SHIFT 16 +#define PR_LIMIT_MASK (0x3fff << PR_LIMIT_SHIFT) +#define PR_RPE BIT(15) +#define PR_BASE_MASK 0x3fff +/* Last PR is GPR0 */ +#define PR_NUM (5 + 1) + +/* Offsets are from @ispi->sregs */ +#define SSFSTS_CTL 0x00 +#define SSFSTS_CTL_FSMIE BIT(23) +#define SSFSTS_CTL_DS BIT(22) +#define SSFSTS_CTL_DBC_SHIFT 16 +#define SSFSTS_CTL_SPOP BIT(11) +#define SSFSTS_CTL_ACS BIT(10) +#define SSFSTS_CTL_SCGO BIT(9) +#define SSFSTS_CTL_COP_SHIFT 12 +#define SSFSTS_CTL_FRS BIT(7) +#define SSFSTS_CTL_DOFRS BIT(6) +#define SSFSTS_CTL_AEL BIT(4) +#define SSFSTS_CTL_FCERR BIT(3) +#define SSFSTS_CTL_FDONE BIT(2) +#define SSFSTS_CTL_SCIP BIT(0) + +#define PREOP_OPTYPE 0x04 +#define OPMENU0 0x08 +#define OPMENU1 0x0c + +/* CPU specifics */ +#define BYT_PR 0x74 +#define BYT_SSFSTS_CTL 0x90 +#define BYT_BCR 0xfc +#define BYT_BCR_WPD BIT(0) +#define BYT_FREG_NUM 5 + +#define LPT_PR 0x74 +#define LPT_SSFSTS_CTL 0x90 +#define LPT_FREG_NUM 5 + +#define BXT_PR 0x84 +#define BXT_SSFSTS_CTL 0xa0 +#define BXT_FREG_NUM 12 + +#define INTEL_SPI_TIMEOUT 5000 /* ms */ +#define INTEL_SPI_FIFO_SZ 64 + +/** + * struct intel_spi - Driver private data + * @dev: Device pointer + * @info: Pointer to board specific info + * @nor: SPI NOR layer structure + * @base: Beginning of MMIO space + * @pregs: Start of protection registers + * @sregs: Start of software sequencer registers + * @nregions: Maximum number of regions + * @writeable: Is the chip writeable + * @swseq: Use SW sequencer in register reads/writes + * @erase_64k: 64k erase supported + * @opcodes: Opcodes which are supported. This are programmed by BIOS + * before it locks down the controller. + * @preopcodes: Preopcodes which are supported. + */ +struct intel_spi { + struct device *dev; + const struct intel_spi_boardinfo *info; + struct spi_nor nor; + void __iomem *base; + void __iomem *pregs; + void __iomem *sregs; + size_t nregions; + bool writeable; + bool swseq; + bool erase_64k; + u8 opcodes[8]; + u8 preopcodes[2]; +}; + +static bool writeable; +module_param(writeable, bool, 0); +MODULE_PARM_DESC(writeable, "Enable write access to SPI flash chip (default=0)"); + +static void intel_spi_dump_regs(struct intel_spi *ispi) +{ + u32 value; + int i; + + dev_dbg(ispi->dev, "BFPREG=0x%08x\n", readl(ispi->base + BFPREG)); + + value = readl(ispi->base + HSFSTS_CTL); + dev_dbg(ispi->dev, "HSFSTS_CTL=0x%08x\n", value); + if (value & HSFSTS_CTL_FLOCKDN) + dev_dbg(ispi->dev, "-> Locked\n"); + + dev_dbg(ispi->dev, "FADDR=0x%08x\n", readl(ispi->base + FADDR)); + dev_dbg(ispi->dev, "DLOCK=0x%08x\n", readl(ispi->base + DLOCK)); + + for (i = 0; i < 16; i++) + dev_dbg(ispi->dev, "FDATA(%d)=0x%08x\n", + i, readl(ispi->base + FDATA(i))); + + dev_dbg(ispi->dev, "FRACC=0x%08x\n", readl(ispi->base + FRACC)); + + for (i = 0; i < ispi->nregions; i++) + dev_dbg(ispi->dev, "FREG(%d)=0x%08x\n", i, + readl(ispi->base + FREG(i))); + for (i = 0; i < PR_NUM; i++) + dev_dbg(ispi->dev, "PR(%d)=0x%08x\n", i, + readl(ispi->pregs + PR(i))); + + value = readl(ispi->sregs + SSFSTS_CTL); + dev_dbg(ispi->dev, "SSFSTS_CTL=0x%08x\n", value); + dev_dbg(ispi->dev, "PREOP_OPTYPE=0x%08x\n", + readl(ispi->sregs + PREOP_OPTYPE)); + dev_dbg(ispi->dev, "OPMENU0=0x%08x\n", readl(ispi->sregs + OPMENU0)); + dev_dbg(ispi->dev, "OPMENU1=0x%08x\n", readl(ispi->sregs + OPMENU1)); + + if (ispi->info->type == INTEL_SPI_BYT) + dev_dbg(ispi->dev, "BCR=0x%08x\n", readl(ispi->base + BYT_BCR)); + + dev_dbg(ispi->dev, "Protected regions:\n"); + for (i = 0; i < PR_NUM; i++) { + u32 base, limit; + + value = readl(ispi->pregs + PR(i)); + if (!(value & (PR_WPE | PR_RPE))) + continue; + + limit = (value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT; + base = value & PR_BASE_MASK; + + dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x [%c%c]\n", + i, base << 12, (limit << 12) | 0xfff, + value & PR_WPE ? 'W' : '.', + value & PR_RPE ? 'R' : '.'); + } + + dev_dbg(ispi->dev, "Flash regions:\n"); + for (i = 0; i < ispi->nregions; i++) { + u32 region, base, limit; + + region = readl(ispi->base + FREG(i)); + base = region & FREG_BASE_MASK; + limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT; + + if (base >= limit || (i > 0 && limit == 0)) + dev_dbg(ispi->dev, " %02d disabled\n", i); + else + dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x\n", + i, base << 12, (limit << 12) | 0xfff); + } + + dev_dbg(ispi->dev, "Using %cW sequencer for register access\n", + ispi->swseq ? 'S' : 'H'); +} + +/* Reads max INTEL_SPI_FIFO_SZ bytes from the device fifo */ +static int intel_spi_read_block(struct intel_spi *ispi, void *buf, size_t size) +{ + size_t bytes; + int i = 0; + + if (size > INTEL_SPI_FIFO_SZ) + return -EINVAL; + + while (size > 0) { + bytes = min_t(size_t, size, 4); + memcpy_fromio(buf, ispi->base + FDATA(i), bytes); + size -= bytes; + buf += bytes; + i++; + } + + return 0; +} + +/* Writes max INTEL_SPI_FIFO_SZ bytes to the device fifo */ +static int intel_spi_write_block(struct intel_spi *ispi, const void *buf, + size_t size) +{ + size_t bytes; + int i = 0; + + if (size > INTEL_SPI_FIFO_SZ) + return -EINVAL; + + while (size > 0) { + bytes = min_t(size_t, size, 4); + memcpy_toio(ispi->base + FDATA(i), buf, bytes); + size -= bytes; + buf += bytes; + i++; + } + + return 0; +} + +static int intel_spi_wait_hw_busy(struct intel_spi *ispi) +{ + u32 val; + + return readl_poll_timeout(ispi->base + HSFSTS_CTL, val, + !(val & HSFSTS_CTL_SCIP), 0, + INTEL_SPI_TIMEOUT * 1000); +} + +static int intel_spi_wait_sw_busy(struct intel_spi *ispi) +{ + u32 val; + + return readl_poll_timeout(ispi->sregs + SSFSTS_CTL, val, + !(val & SSFSTS_CTL_SCIP), 0, + INTEL_SPI_TIMEOUT * 1000); +} + +static int intel_spi_init(struct intel_spi *ispi) +{ + u32 opmenu0, opmenu1, val; + int i; + + switch (ispi->info->type) { + case INTEL_SPI_BYT: + ispi->sregs = ispi->base + BYT_SSFSTS_CTL; + ispi->pregs = ispi->base + BYT_PR; + ispi->nregions = BYT_FREG_NUM; + + if (writeable) { + /* Disable write protection */ + val = readl(ispi->base + BYT_BCR); + if (!(val & BYT_BCR_WPD)) { + val |= BYT_BCR_WPD; + writel(val, ispi->base + BYT_BCR); + val = readl(ispi->base + BYT_BCR); + } + + ispi->writeable = !!(val & BYT_BCR_WPD); + } + + break; + + case INTEL_SPI_LPT: + ispi->sregs = ispi->base + LPT_SSFSTS_CTL; + ispi->pregs = ispi->base + LPT_PR; + ispi->nregions = LPT_FREG_NUM; + break; + + case INTEL_SPI_BXT: + ispi->sregs = ispi->base + BXT_SSFSTS_CTL; + ispi->pregs = ispi->base + BXT_PR; + ispi->nregions = BXT_FREG_NUM; + ispi->erase_64k = true; + break; + + default: + return -EINVAL; + } + + /* Disable #SMI generation */ + val = readl(ispi->base + HSFSTS_CTL); + val &= ~HSFSTS_CTL_FSMIE; + writel(val, ispi->base + HSFSTS_CTL); + + /* + * BIOS programs allowed opcodes and then locks down the register. + * So read back what opcodes it decided to support. That's the set + * we are going to support as well. + */ + opmenu0 = readl(ispi->sregs + OPMENU0); + opmenu1 = readl(ispi->sregs + OPMENU1); + + /* + * Some controllers can only do basic operations using hardware + * sequencer. All other operations are supposed to be carried out + * using software sequencer. If we find that BIOS has programmed + * opcodes for the software sequencer we use that over the hardware + * sequencer. + */ + if (opmenu0 && opmenu1) { + for (i = 0; i < ARRAY_SIZE(ispi->opcodes) / 2; i++) { + ispi->opcodes[i] = opmenu0 >> i * 8; + ispi->opcodes[i + 4] = opmenu1 >> i * 8; + } + + val = readl(ispi->sregs + PREOP_OPTYPE); + ispi->preopcodes[0] = val; + ispi->preopcodes[1] = val >> 8; + + /* Disable #SMI generation from SW sequencer */ + val = readl(ispi->sregs + SSFSTS_CTL); + val &= ~SSFSTS_CTL_FSMIE; + writel(val, ispi->sregs + SSFSTS_CTL); + + ispi->swseq = true; + } + + intel_spi_dump_regs(ispi); + + return 0; +} + +static int intel_spi_opcode_index(struct intel_spi *ispi, u8 opcode) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ispi->opcodes); i++) + if (ispi->opcodes[i] == opcode) + return i; + return -EINVAL; +} + +static int intel_spi_hw_cycle(struct intel_spi *ispi, u8 opcode, u8 *buf, + int len) +{ + u32 val, status; + int ret; + + val = readl(ispi->base + HSFSTS_CTL); + val &= ~(HSFSTS_CTL_FCYCLE_MASK | HSFSTS_CTL_FDBC_MASK); + + switch (opcode) { + case SPINOR_OP_RDID: + val |= HSFSTS_CTL_FCYCLE_RDID; + break; + case SPINOR_OP_WRSR: + val |= HSFSTS_CTL_FCYCLE_WRSR; + break; + case SPINOR_OP_RDSR: + val |= HSFSTS_CTL_FCYCLE_RDSR; + break; + default: + return -EINVAL; + } + + val |= (len - 1) << HSFSTS_CTL_FDBC_SHIFT; + val |= HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE; + val |= HSFSTS_CTL_FGO; + writel(val, ispi->base + HSFSTS_CTL); + + ret = intel_spi_wait_hw_busy(ispi); + if (ret) + return ret; + + status = readl(ispi->base + HSFSTS_CTL); + if (status & HSFSTS_CTL_FCERR) + return -EIO; + else if (status & HSFSTS_CTL_AEL) + return -EACCES; + + return 0; +} + +static int intel_spi_sw_cycle(struct intel_spi *ispi, u8 opcode, u8 *buf, + int len) +{ + u32 val, status; + int ret; + + ret = intel_spi_opcode_index(ispi, opcode); + if (ret < 0) + return ret; + + val = (len << SSFSTS_CTL_DBC_SHIFT) | SSFSTS_CTL_DS; + val |= ret << SSFSTS_CTL_COP_SHIFT; + val |= SSFSTS_CTL_FCERR | SSFSTS_CTL_FDONE; + val |= SSFSTS_CTL_SCGO; + writel(val, ispi->sregs + SSFSTS_CTL); + + ret = intel_spi_wait_sw_busy(ispi); + if (ret) + return ret; + + status = readl(ispi->base + SSFSTS_CTL); + if (status & SSFSTS_CTL_FCERR) + return -EIO; + else if (status & SSFSTS_CTL_AEL) + return -EACCES; + + return 0; +} + +static int intel_spi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) +{ + struct intel_spi *ispi = nor->priv; + int ret; + + /* Address of the first chip */ + writel(0, ispi->base + FADDR); + + if (ispi->swseq) + ret = intel_spi_sw_cycle(ispi, opcode, buf, len); + else + ret = intel_spi_hw_cycle(ispi, opcode, buf, len); + + if (ret) + return ret; + + return intel_spi_read_block(ispi, buf, len); +} + +static int intel_spi_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) +{ + struct intel_spi *ispi = nor->priv; + int ret; + + /* + * This is handled with atomic operation and preop code in Intel + * controller so skip it here now. + */ + if (opcode == SPINOR_OP_WREN) + return 0; + + writel(0, ispi->base + FADDR); + + /* Write the value beforehand */ + ret = intel_spi_write_block(ispi, buf, len); + if (ret) + return ret; + + if (ispi->swseq) + return intel_spi_sw_cycle(ispi, opcode, buf, len); + return intel_spi_hw_cycle(ispi, opcode, buf, len); +} + +static ssize_t intel_spi_read(struct spi_nor *nor, loff_t from, size_t len, + u_char *read_buf) +{ + struct intel_spi *ispi = nor->priv; + size_t block_size, retlen = 0; + u32 val, status; + ssize_t ret; + + switch (nor->read_opcode) { + case SPINOR_OP_READ: + case SPINOR_OP_READ_FAST: + break; + default: + return -EINVAL; + } + + while (len > 0) { + block_size = min_t(size_t, len, INTEL_SPI_FIFO_SZ); + + writel(from, ispi->base + FADDR); + + val = readl(ispi->base + HSFSTS_CTL); + val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK); + val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE; + val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT; + val |= HSFSTS_CTL_FCYCLE_READ; + val |= HSFSTS_CTL_FGO; + writel(val, ispi->base + HSFSTS_CTL); + + ret = intel_spi_wait_hw_busy(ispi); + if (ret) + return ret; + + status = readl(ispi->base + HSFSTS_CTL); + if (status & HSFSTS_CTL_FCERR) + ret = -EIO; + else if (status & HSFSTS_CTL_AEL) + ret = -EACCES; + + if (ret < 0) { + dev_err(ispi->dev, "read error: %llx: %#x\n", from, + status); + return ret; + } + + ret = intel_spi_read_block(ispi, read_buf, block_size); + if (ret) + return ret; + + len -= block_size; + from += block_size; + retlen += block_size; + read_buf += block_size; + } + + return retlen; +} + +static ssize_t intel_spi_write(struct spi_nor *nor, loff_t to, size_t len, + const u_char *write_buf) +{ + struct intel_spi *ispi = nor->priv; + size_t block_size, retlen = 0; + u32 val, status; + ssize_t ret; + + while (len > 0) { + block_size = min_t(size_t, len, INTEL_SPI_FIFO_SZ); + + writel(to, ispi->base + FADDR); + + val = readl(ispi->base + HSFSTS_CTL); + val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK); + val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE; + val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT; + val |= HSFSTS_CTL_FCYCLE_WRITE; + + /* Write enable */ + if (ispi->preopcodes[1] == SPINOR_OP_WREN) + val |= SSFSTS_CTL_SPOP; + val |= SSFSTS_CTL_ACS; + writel(val, ispi->base + HSFSTS_CTL); + + ret = intel_spi_write_block(ispi, write_buf, block_size); + if (ret) { + dev_err(ispi->dev, "failed to write block\n"); + return ret; + } + + /* Start the write now */ + val = readl(ispi->base + HSFSTS_CTL); + writel(val | HSFSTS_CTL_FGO, ispi->base + HSFSTS_CTL); + + ret = intel_spi_wait_hw_busy(ispi); + if (ret) { + dev_err(ispi->dev, "timeout\n"); + return ret; + } + + status = readl(ispi->base + HSFSTS_CTL); + if (status & HSFSTS_CTL_FCERR) + ret = -EIO; + else if (status & HSFSTS_CTL_AEL) + ret = -EACCES; + + if (ret < 0) { + dev_err(ispi->dev, "write error: %llx: %#x\n", to, + status); + return ret; + } + + len -= block_size; + to += block_size; + retlen += block_size; + write_buf += block_size; + } + + return retlen; +} + +static int intel_spi_erase(struct spi_nor *nor, loff_t offs) +{ + size_t erase_size, len = nor->mtd.erasesize; + struct intel_spi *ispi = nor->priv; + u32 val, status, cmd; + int ret; + + /* If the hardware can do 64k erase use that when possible */ + if (len >= SZ_64K && ispi->erase_64k) { + cmd = HSFSTS_CTL_FCYCLE_ERASE_64K; + erase_size = SZ_64K; + } else { + cmd = HSFSTS_CTL_FCYCLE_ERASE; + erase_size = SZ_4K; + } + + while (len > 0) { + writel(offs, ispi->base + FADDR); + + val = readl(ispi->base + HSFSTS_CTL); + val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK); + val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE; + val |= cmd; + val |= HSFSTS_CTL_FGO; + writel(val, ispi->base + HSFSTS_CTL); + + ret = intel_spi_wait_hw_busy(ispi); + if (ret) + return ret; + + status = readl(ispi->base + HSFSTS_CTL); + if (status & HSFSTS_CTL_FCERR) + return -EIO; + else if (status & HSFSTS_CTL_AEL) + return -EACCES; + + offs += erase_size; + len -= erase_size; + } + + return 0; +} + +static bool intel_spi_is_protected(const struct intel_spi *ispi, + unsigned int base, unsigned int limit) +{ + int i; + + for (i = 0; i < PR_NUM; i++) { + u32 pr_base, pr_limit, pr_value; + + pr_value = readl(ispi->pregs + PR(i)); + if (!(pr_value & (PR_WPE | PR_RPE))) + continue; + + pr_limit = (pr_value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT; + pr_base = pr_value & PR_BASE_MASK; + + if (pr_base >= base && pr_limit <= limit) + return true; + } + + return false; +} + +/* + * There will be a single partition holding all enabled flash regions. We + * call this "BIOS". + */ +static void intel_spi_fill_partition(struct intel_spi *ispi, + struct mtd_partition *part) +{ + u64 end; + int i; + + memset(part, 0, sizeof(*part)); + + /* Start from the mandatory descriptor region */ + part->size = 4096; + part->name = "BIOS"; + + /* + * Now try to find where this partition ends based on the flash + * region registers. + */ + for (i = 1; i < ispi->nregions; i++) { + u32 region, base, limit; + + region = readl(ispi->base + FREG(i)); + base = region & FREG_BASE_MASK; + limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT; + + if (base >= limit || limit == 0) + continue; + + /* + * If any of the regions have protection bits set, make the + * whole partition read-only to be on the safe side. + */ + if (intel_spi_is_protected(ispi, base, limit)) + ispi->writeable = 0; + + end = (limit << 12) + 4096; + if (end > part->size) + part->size = end; + } +} + +struct intel_spi *intel_spi_probe(struct device *dev, + struct resource *mem, const struct intel_spi_boardinfo *info) +{ + struct mtd_partition part; + struct intel_spi *ispi; + int ret; + + if (!info || !mem) + return ERR_PTR(-EINVAL); + + ispi = devm_kzalloc(dev, sizeof(*ispi), GFP_KERNEL); + if (!ispi) + return ERR_PTR(-ENOMEM); + + ispi->base = devm_ioremap_resource(dev, mem); + if (IS_ERR(ispi->base)) + return ispi->base; + + ispi->dev = dev; + ispi->info = info; + ispi->writeable = info->writeable; + + ret = intel_spi_init(ispi); + if (ret) + return ERR_PTR(ret); + + ispi->nor.dev = ispi->dev; + ispi->nor.priv = ispi; + ispi->nor.read_reg = intel_spi_read_reg; + ispi->nor.write_reg = intel_spi_write_reg; + ispi->nor.read = intel_spi_read; + ispi->nor.write = intel_spi_write; + ispi->nor.erase = intel_spi_erase; + + ret = spi_nor_scan(&ispi->nor, NULL, SPI_NOR_NORMAL); + if (ret) { + dev_info(dev, "failed to locate the chip\n"); + return ERR_PTR(ret); + } + + intel_spi_fill_partition(ispi, &part); + + /* Prevent writes if not explicitly enabled */ + if (!ispi->writeable || !writeable) + ispi->nor.mtd.flags &= ~MTD_WRITEABLE; + + ret = mtd_device_parse_register(&ispi->nor.mtd, NULL, NULL, &part, 1); + if (ret) + return ERR_PTR(ret); + + return ispi; +} +EXPORT_SYMBOL_GPL(intel_spi_probe); + +int intel_spi_remove(struct intel_spi *ispi) +{ + return mtd_device_unregister(&ispi->nor.mtd); +} +EXPORT_SYMBOL_GPL(intel_spi_remove); + +MODULE_DESCRIPTION("Intel PCH/PCU SPI flash core driver"); +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/mtd/spi-nor/intel-spi.h b/drivers/mtd/spi-nor/intel-spi.h new file mode 100644 index 000000000000..5ab7dc250050 --- /dev/null +++ b/drivers/mtd/spi-nor/intel-spi.h @@ -0,0 +1,24 @@ +/* + * Intel PCH/PCU SPI flash driver. + * + * Copyright (C) 2016, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * 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. + */ + +#ifndef INTEL_SPI_H +#define INTEL_SPI_H + +#include <linux/platform_data/intel-spi.h> + +struct intel_spi; +struct resource; + +struct intel_spi *intel_spi_probe(struct device *dev, + struct resource *mem, const struct intel_spi_boardinfo *info); +int intel_spi_remove(struct intel_spi *ispi); + +#endif /* INTEL_SPI_H */ diff --git a/include/linux/platform_data/intel-spi.h b/include/linux/platform_data/intel-spi.h new file mode 100644 index 000000000000..942b0c3f8f08 --- /dev/null +++ b/include/linux/platform_data/intel-spi.h @@ -0,0 +1,31 @@ +/* + * Intel PCH/PCU SPI flash driver. + * + * Copyright (C) 2016, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * 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. + */ + +#ifndef INTEL_SPI_PDATA_H +#define INTEL_SPI_PDATA_H + +enum intel_spi_type { + INTEL_SPI_BYT = 1, + INTEL_SPI_LPT, + INTEL_SPI_BXT, +}; + +/** + * struct intel_spi_boardinfo - Board specific data for Intel SPI driver + * @type: Type which this controller is compatible with + * @writeable: The chip is writeable + */ +struct intel_spi_boardinfo { + enum intel_spi_type type; + bool writeable; +}; + +#endif /* INTEL_SPI_PDATA_H */ |