From: <atull@opensource.altera.com>
To: gregkh@linuxfoundation.org, jgunthorpe@obsidianresearch.com,
hpa@zytor.com, monstr@monstr.eu, michal.simek@xilinx.com,
rdunlap@infradead.org
Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
pantelis.antoniou@konsulko.com, robh+dt@kernel.org,
grant.likely@linaro.org, iws@ovro.caltech.edu,
linux-doc@vger.kernel.org, pavel@denx.de, broonie@kernel.org,
philip@balister.org, rubini@gnudd.com, s.trumtrar@pengutronix.de,
jason@lakedaemon.net, kyle.teske@ni.com, nico@linaro.org,
balbi@ti.com, m.chehab@samsung.com, davidb@codeaurora.org,
rob@landley.net, davem@davemloft.net, cesarb@cesarb.net,
sameo@linux.intel.com, akpm@linux-foundation.org,
linus.walleij@linaro.org, pawel.moll@arm.com,
mark.rutland@arm.com, ijc+devicetree@hellion.org.uk,
galak@codeaurora.org, devel@driverdev.osuosl.org,
delicious.quinoa@gmail.com, dinguyen@opensource.altera.com,
yvanderv@opensource.altera.com,
Alan Tull <atull@opensource.altera.com>
Subject: [PATCH v6 4/4] staging: fpga manager: add driver for socfpga fpga manager
Date: Thu, 18 Dec 2014 16:29:08 -0600 [thread overview]
Message-ID: <1418941748-16111-5-git-send-email-atull@opensource.altera.com> (raw)
In-Reply-To: <1418941748-16111-1-git-send-email-atull@opensource.altera.com>
From: Alan Tull <atull@opensource.altera.com>
Add driver to fpga manager framework to allow configuration
of FPGA in Altera SoCFPGA parts.
Signed-off-by: Alan Tull <atull@opensource.altera.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
---
v2: fpga_manager struct now contains struct device
fpga_manager_register parameters now take device
v3: skip a version to align versions
v4: move to drivers/staging
v5: fix array_size.cocci warnings
fix platform_no_drv_owner.cocci warnings
Remove .owner = THIS_MODULE
include asm/irq.h
clean up list of includes
use altera_fpga_reset for ops
use enum fpga_mgr_states or u32 as needed
use devm_request_irq
check irq <= 0 instead of == NO_IRQ
Use ARRAY_SIZE
rename altera -> socfpga
static const socfpga_fpga_ops
header moved to linux/fpga/ folder
remove ifdef'ed code
use platform_get_resource and platform_get_irq
move .probe and .remove lines adjacent
use module_platform_driver
use __maybe_unused
only need to 'if (IS_ENABLED(CONFIG_REGULATOR))' in one fn
fix "unsigned 'mode' is never < 0"
v6: return error for (unused) default of case statement
---
drivers/staging/fpga/Kconfig | 5 +
drivers/staging/fpga/Makefile | 1 +
drivers/staging/fpga/socfpga.c | 694 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 700 insertions(+)
create mode 100644 drivers/staging/fpga/socfpga.c
diff --git a/drivers/staging/fpga/Kconfig b/drivers/staging/fpga/Kconfig
index 89ebafc..ce17342 100644
--- a/drivers/staging/fpga/Kconfig
+++ b/drivers/staging/fpga/Kconfig
@@ -19,6 +19,11 @@ config FPGA_MGR_SYSFS
help
FPGA Manager SysFS interface.
+config FPGA_MGR_SOCFPGA
+ tristate "Altera SOCFPGA"
+ help
+ FPGA manager driver support for Altera SOCFPGA.
+
endif # FPGA
endmenu
diff --git a/drivers/staging/fpga/Makefile b/drivers/staging/fpga/Makefile
index 3313c52..ba6c5c5 100644
--- a/drivers/staging/fpga/Makefile
+++ b/drivers/staging/fpga/Makefile
@@ -6,3 +6,4 @@
obj-$(CONFIG_FPGA) += fpga-mgr.o
# FPGA Manager Drivers
+obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o
diff --git a/drivers/staging/fpga/socfpga.c b/drivers/staging/fpga/socfpga.c
new file mode 100644
index 0000000..aa96e43
--- /dev/null
+++ b/drivers/staging/fpga/socfpga.c
@@ -0,0 +1,694 @@
+/*
+ * FPGA Manager Driver for Altera SOCFPGA
+ *
+ * Copyright (C) 2013-2014 Altera Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/pm.h>
+#include <linux/string.h>
+#include <linux/regulator/consumer.h>
+
+/* Register offsets */
+#define SOCFPGA_FPGMGR_STAT_OFST 0x0
+#define SOCFPGA_FPGMGR_CTL_OFST 0x4
+#define SOCFPGA_FPGMGR_DCLKCNT_OFST 0x8
+#define SOCFPGA_FPGMGR_DCLKSTAT_OFST 0xc
+#define SOCFPGA_FPGMGR_GPIO_INTEN_OFST 0x830
+#define SOCFPGA_FPGMGR_GPIO_INTMSK_OFST 0x834
+#define SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST 0x838
+#define SOCFPGA_FPGMGR_GPIO_INT_POL_OFST 0x83c
+#define SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST 0x840
+#define SOCFPGA_FPGMGR_GPIO_RAW_INTSTAT_OFST 0x844
+#define SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST 0x84c
+#define SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST 0x850
+
+/* Register bit defines */
+/* SOCFPGA_FPGMGR_STAT register mode field values */
+#define SOCFPGA_FPGMGR_STAT_POWER_UP 0x0 /*ramping*/
+#define SOCFPGA_FPGMGR_STAT_RESET 0x1
+#define SOCFPGA_FPGMGR_STAT_CFG 0x2
+#define SOCFPGA_FPGMGR_STAT_INIT 0x3
+#define SOCFPGA_FPGMGR_STAT_USER_MODE 0x4
+#define SOCFPGA_FPGMGR_STAT_UNKNOWN 0x5
+#define SOCFPGA_FPGMGR_STAT_STATE_MASK 0x7
+/* This is a flag value that doesn't really happen in this register field */
+#define SOCFPGA_FPGMGR_STAT_POWER_OFF 0x0
+
+#define MSEL_PP16_FAST_NOAES_NODC 0x0
+#define MSEL_PP16_FAST_AES_NODC 0x1
+#define MSEL_PP16_FAST_AESOPT_DC 0x2
+#define MSEL_PP16_SLOW_NOAES_NODC 0x4
+#define MSEL_PP16_SLOW_AES_NODC 0x5
+#define MSEL_PP16_SLOW_AESOPT_DC 0x6
+#define MSEL_PP32_FAST_NOAES_NODC 0x8
+#define MSEL_PP32_FAST_AES_NODC 0x9
+#define MSEL_PP32_FAST_AESOPT_DC 0xa
+#define MSEL_PP32_SLOW_NOAES_NODC 0xc
+#define MSEL_PP32_SLOW_AES_NODC 0xd
+#define MSEL_PP32_SLOW_AESOPT_DC 0xe
+#define SOCFPGA_FPGMGR_STAT_MSEL_MASK 0x000000f8
+#define SOCFPGA_FPGMGR_STAT_MSEL_SHIFT 3
+
+/* SOCFPGA_FPGMGR_CTL register */
+#define SOCFPGA_FPGMGR_CTL_EN 0x00000001
+#define SOCFPGA_FPGMGR_CTL_NCE 0x00000002
+#define SOCFPGA_FPGMGR_CTL_NCFGPULL 0x00000004
+
+#define CDRATIO_X1 0x00000000
+#define CDRATIO_X2 0x00000040
+#define CDRATIO_X4 0x00000080
+#define CDRATIO_X8 0x000000c0
+#define SOCFPGA_FPGMGR_CTL_CDRATIO_MASK 0x000000c0
+
+#define SOCFPGA_FPGMGR_CTL_AXICFGEN 0x00000100
+
+#define CFGWDTH_16 0x00000000
+#define CFGWDTH_32 0x00000200
+#define SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK 0x00000200
+
+/* SOCFPGA_FPGMGR_DCLKSTAT register */
+#define SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE 0x1
+
+/* SOCFPGA_FPGMGR_GPIO_* registers share the same bit positions */
+#define SOCFPGA_FPGMGR_MON_NSTATUS 0x0001
+#define SOCFPGA_FPGMGR_MON_CONF_DONE 0x0002
+#define SOCFPGA_FPGMGR_MON_INIT_DONE 0x0004
+#define SOCFPGA_FPGMGR_MON_CRC_ERROR 0x0008
+#define SOCFPGA_FPGMGR_MON_CVP_CONF_DONE 0x0010
+#define SOCFPGA_FPGMGR_MON_PR_READY 0x0020
+#define SOCFPGA_FPGMGR_MON_PR_ERROR 0x0040
+#define SOCFPGA_FPGMGR_MON_PR_DONE 0x0080
+#define SOCFPGA_FPGMGR_MON_NCONFIG_PIN 0x0100
+#define SOCFPGA_FPGMGR_MON_NSTATUS_PIN 0x0200
+#define SOCFPGA_FPGMGR_MON_CONF_DONE_PIN 0x0400
+#define SOCFPGA_FPGMGR_MON_FPGA_POWER_ON 0x0800
+#define SOCFPGA_FPGMGR_MON_STATUS_MASK 0x0fff
+
+#define SOCFPGA_FPGMGR_NUM_SUPPLIES 3
+#define SOCFPGA_RESUME_TIMEOUT 3
+
+/* In power-up order. Reverse for power-down. */
+static const char *supply_names[SOCFPGA_FPGMGR_NUM_SUPPLIES] __maybe_unused = {
+ "FPGA-1.5V",
+ "FPGA-1.1V",
+ "FPGA-2.5V",
+};
+
+struct socfpga_fpga_priv {
+ void __iomem *fpga_base_addr;
+ void __iomem *fpga_data_addr;
+ struct completion status_complete;
+ int irq;
+ struct regulator *fpga_supplies[SOCFPGA_FPGMGR_NUM_SUPPLIES];
+};
+
+struct cfgmgr_mode {
+ /* Values to set in the CTRL register */
+ u32 ctrl;
+
+ /* flag that this table entry is a valid mode */
+ bool valid;
+};
+
+/* For SOCFPGA_FPGMGR_STAT_MSEL field */
+static struct cfgmgr_mode cfgmgr_modes[] = {
+ [MSEL_PP16_FAST_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
+ [MSEL_PP16_FAST_AES_NODC] = { CFGWDTH_16 | CDRATIO_X2, 1 },
+ [MSEL_PP16_FAST_AESOPT_DC] = { CFGWDTH_16 | CDRATIO_X4, 1 },
+ [MSEL_PP16_SLOW_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
+ [MSEL_PP16_SLOW_AES_NODC] = { CFGWDTH_16 | CDRATIO_X2, 1 },
+ [MSEL_PP16_SLOW_AESOPT_DC] = { CFGWDTH_16 | CDRATIO_X4, 1 },
+ [MSEL_PP32_FAST_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
+ [MSEL_PP32_FAST_AES_NODC] = { CFGWDTH_32 | CDRATIO_X4, 1 },
+ [MSEL_PP32_FAST_AESOPT_DC] = { CFGWDTH_32 | CDRATIO_X8, 1 },
+ [MSEL_PP32_SLOW_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
+ [MSEL_PP32_SLOW_AES_NODC] = { CFGWDTH_32 | CDRATIO_X4, 1 },
+ [MSEL_PP32_SLOW_AESOPT_DC] = { CFGWDTH_32 | CDRATIO_X8, 1 },
+};
+
+static u32 socfpga_fpga_readl(struct socfpga_fpga_priv *priv, u32 reg_offset)
+{
+ return readl(priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_writel(struct socfpga_fpga_priv *priv, u32 reg_offset,
+ u32 value)
+{
+ writel(value, priv->fpga_base_addr + reg_offset);
+}
+
+static u32 socfpga_fpga_raw_readl(struct socfpga_fpga_priv *priv,
+ u32 reg_offset)
+{
+ return __raw_readl(priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_raw_writel(struct socfpga_fpga_priv *priv,
+ u32 reg_offset, u32 value)
+{
+ __raw_writel(value, priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_data_writel(struct socfpga_fpga_priv *priv, u32 value)
+{
+ writel(value, priv->fpga_data_addr);
+}
+
+static inline void socfpga_fpga_set_bitsl(struct socfpga_fpga_priv *priv,
+ u32 offset, u32 bits)
+{
+ u32 val;
+
+ val = socfpga_fpga_readl(priv, offset);
+ val |= bits;
+ socfpga_fpga_writel(priv, offset, val);
+}
+
+static inline void socfpga_fpga_clr_bitsl(struct socfpga_fpga_priv *priv,
+ u32 offset, u32 bits)
+{
+ u32 val;
+
+ val = socfpga_fpga_readl(priv, offset);
+ val &= ~bits;
+ socfpga_fpga_writel(priv, offset, val);
+}
+
+static u32 socfpga_fpga_mon_status_get(struct socfpga_fpga_priv *priv)
+{
+ return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST) &
+ SOCFPGA_FPGMGR_MON_STATUS_MASK;
+}
+
+static u32 socfpga_fpga_state_get(struct socfpga_fpga_priv *priv)
+{
+ u32 status = socfpga_fpga_mon_status_get(priv);
+
+ if ((status & SOCFPGA_FPGMGR_MON_FPGA_POWER_ON) == 0)
+ return SOCFPGA_FPGMGR_STAT_POWER_OFF;
+
+ return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST) &
+ SOCFPGA_FPGMGR_STAT_STATE_MASK;
+}
+
+static void socfpga_fpga_clear_done_status(struct socfpga_fpga_priv *priv)
+{
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST,
+ SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE);
+}
+
+/*
+ * Set the DCLKCNT, wait for DCLKSTAT to report the count completed, and clear
+ * the complete status.
+ */
+static int socfpga_fpga_dclk_set_and_wait_clear(struct socfpga_fpga_priv *priv,
+ u32 count)
+{
+ int timeout = 2;
+ u32 done;
+
+ /* Clear any existing DONE status. */
+ if (socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST))
+ socfpga_fpga_clear_done_status(priv);
+
+ /* Issue the DCLK count. */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKCNT_OFST, count);
+
+ /* Poll DCLKSTAT to see if it completed in the timeout period. */
+ do {
+ done = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST);
+ if (done == SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE) {
+ socfpga_fpga_clear_done_status(priv);
+ return 0;
+ }
+ udelay(1);
+ } while (timeout--);
+
+ return -ETIMEDOUT;
+}
+
+static int socfpga_fpga_wait_for_state(struct socfpga_fpga_priv *priv,
+ u32 state)
+{
+ int timeout = 2;
+
+ /*
+ * HW doesn't support an interrupt for changes in state, so poll to see
+ * if it matches the requested state within the timeout period.
+ */
+ do {
+ if ((socfpga_fpga_state_get(priv) & state) != 0)
+ return 0;
+ msleep(20);
+ } while (timeout--);
+
+ return -ETIMEDOUT;
+}
+
+static void socfpga_fpga_enable_irqs(struct socfpga_fpga_priv *priv, u32 irqs)
+{
+ /* set irqs to level sensitive */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST, 0);
+
+ /* set interrupt polarity */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INT_POL_OFST, irqs);
+
+ /* clear irqs */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
+
+ /* unmask interrupts */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTMSK_OFST, 0);
+
+ /* enable interrupts */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, irqs);
+}
+
+static void socfpga_fpga_disable_irqs(struct socfpga_fpga_priv *priv)
+{
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
+}
+
+static irqreturn_t socfpga_fpga_isr(int irq, void *dev_id)
+{
+ struct socfpga_fpga_priv *priv = dev_id;
+ u32 irqs, st;
+ bool conf_done, nstatus;
+
+ /* clear irqs */
+ irqs = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST);
+
+ socfpga_fpga_raw_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
+
+ st = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST);
+ conf_done = (st & SOCFPGA_FPGMGR_MON_CONF_DONE) != 0;
+ nstatus = (st & SOCFPGA_FPGMGR_MON_NSTATUS) != 0;
+
+ /* success */
+ if (conf_done && nstatus) {
+ /* disable irqs */
+ socfpga_fpga_raw_writel(priv,
+ SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
+ complete(&priv->status_complete);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int socfpga_fpga_wait_for_config_done(struct socfpga_fpga_priv *priv)
+{
+ int timeout, ret = 0;
+
+ socfpga_fpga_disable_irqs(priv);
+ init_completion(&priv->status_complete);
+ socfpga_fpga_enable_irqs(priv, SOCFPGA_FPGMGR_MON_CONF_DONE);
+
+ timeout = wait_for_completion_interruptible_timeout(
+ &priv->status_complete,
+ msecs_to_jiffies(10));
+ if (timeout == 0)
+ ret = -ETIMEDOUT;
+
+ socfpga_fpga_disable_irqs(priv);
+ return ret;
+}
+
+static int socfpga_fpga_cfg_mode_get(struct socfpga_fpga_priv *priv)
+{
+ u32 msel;
+
+ msel = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST);
+ msel &= SOCFPGA_FPGMGR_STAT_MSEL_MASK;
+ msel >>= SOCFPGA_FPGMGR_STAT_MSEL_SHIFT;
+
+ /* Check that this MSEL setting is supported */
+ if ((msel >= ARRAY_SIZE(cfgmgr_modes)) || !cfgmgr_modes[msel].valid)
+ return -EINVAL;
+
+ return msel;
+}
+
+static int socfpga_fpga_cfg_mode_set(struct socfpga_fpga_priv *priv)
+{
+ u32 ctrl_reg;
+ int mode;
+
+ /* get value from MSEL pins */
+ mode = socfpga_fpga_cfg_mode_get(priv);
+ if (mode < 0)
+ return mode;
+
+ /* Adjust CTRL for the CDRATIO */
+ ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CDRATIO_MASK;
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK;
+ ctrl_reg |= cfgmgr_modes[mode].ctrl;
+
+ /* Set NCE to 0. */
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCE;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ return 0;
+}
+
+static int socfpga_fpga_reset(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 ctrl_reg, status;
+ int ret;
+
+ /*
+ * Step 1:
+ * - Set CTRL.CFGWDTH, CTRL.CDRATIO to match cfg mode
+ * - Set CTRL.NCE to 0
+ */
+ ret = socfpga_fpga_cfg_mode_set(priv);
+ if (ret)
+ return ret;
+
+ /* Step 2: Set CTRL.EN to 1 */
+ socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_EN);
+
+ /* Step 3: Set CTRL.NCONFIGPULL to 1 to put FPGA in reset */
+ ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
+ ctrl_reg |= SOCFPGA_FPGMGR_CTL_NCFGPULL;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ /* Step 4: Wait for STATUS.MODE to report FPGA is in reset phase */
+ status = socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_RESET);
+
+ /* Step 5: Set CONTROL.NCONFIGPULL to 0 to release FPGA from reset */
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCFGPULL;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ /* Timeout waiting for reset */
+ if (status)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+/*
+ * Prepare the FPGA to receive the configuration data.
+ */
+static int socfpga_fpga_ops_configure_init(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ int ret;
+
+ /* Steps 1 - 5: Reset the FPGA */
+ ret = socfpga_fpga_reset(mgr);
+ if (ret)
+ return ret;
+
+ /* Step 6: Wait for FPGA to enter configuration phase */
+ if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_CFG))
+ return -ETIMEDOUT;
+
+ /* Step 7: Clear nSTATUS interrupt */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST,
+ SOCFPGA_FPGMGR_MON_NSTATUS);
+
+ /* Step 8: Set CTRL.AXICFGEN to 1 to enable transfer of config data */
+ socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_AXICFGEN);
+
+ return 0;
+}
+
+/*
+ * Step 9: write data to the FPGA data register
+ */
+static int socfpga_fpga_ops_configure_write(struct fpga_manager *mgr,
+ const char *buf, size_t count)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 *buffer_32 = (u32 *)buf;
+ size_t i = 0;
+
+ if (count <= 0)
+ return -EINVAL;
+
+ /* Write out the complete 32-bit chunks. */
+ while (count >= sizeof(u32)) {
+ socfpga_fpga_data_writel(priv, buffer_32[i++]);
+ count -= sizeof(u32);
+ }
+
+ /* Write out remaining non 32-bit chunks. */
+ switch (count) {
+ case 3:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x00ffffff);
+ break;
+ case 2:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x0000ffff);
+ break;
+ case 1:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x000000ff);
+ break;
+ case 0:
+ break;
+ default:
+ /* This will never happen. */
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+static int socfpga_fpga_ops_configure_complete(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 status;
+
+ /*
+ * Step 10:
+ * - Observe CONF_DONE and nSTATUS (active low)
+ * - if CONF_DONE = 1 and nSTATUS = 1, configuration was successful
+ * - if CONF_DONE = 0 and nSTATUS = 0, configuration failed
+ */
+ status = socfpga_fpga_wait_for_config_done(priv);
+ if (status)
+ return status;
+
+ /* Step 11: Clear CTRL.AXICFGEN to disable transfer of config data */
+ socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_AXICFGEN);
+
+ /*
+ * Step 12:
+ * - Write 4 to DCLKCNT
+ * - Wait for STATUS.DCNTDONE = 1
+ * - Clear W1C bit in STATUS.DCNTDONE
+ */
+ if (socfpga_fpga_dclk_set_and_wait_clear(priv, 4))
+ return -ETIMEDOUT;
+
+ /* Step 13: Wait for STATUS.MODE to report USER MODE */
+ if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_USER_MODE))
+ return -ETIMEDOUT;
+
+ /* Step 14: Set CTRL.EN to 0 */
+ socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_EN);
+
+ return 0;
+}
+
+/* Translate state register values to FPGA framework state */
+static const enum fpga_mgr_states socfpga_state_to_framework_state[] = {
+ [SOCFPGA_FPGMGR_STAT_POWER_OFF] = FPGA_MGR_STATE_POWER_OFF,
+ [SOCFPGA_FPGMGR_STAT_RESET] = FPGA_MGR_STATE_RESET,
+ [SOCFPGA_FPGMGR_STAT_CFG] = FPGA_MGR_STATE_WRITE_INIT,
+ [SOCFPGA_FPGMGR_STAT_INIT] = FPGA_MGR_STATE_WRITE_INIT,
+ [SOCFPGA_FPGMGR_STAT_USER_MODE] = FPGA_MGR_STATE_OPERATING,
+ [SOCFPGA_FPGMGR_STAT_UNKNOWN] = FPGA_MGR_STATE_UNKNOWN,
+};
+
+static enum fpga_mgr_states socfpga_fpga_ops_state(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ enum fpga_mgr_states ret;
+ u32 state;
+
+ state = socfpga_fpga_state_get(priv);
+
+ if (state < ARRAY_SIZE(socfpga_state_to_framework_state))
+ ret = socfpga_state_to_framework_state[state];
+ else
+ ret = FPGA_MGR_STATE_UNKNOWN;
+
+ return ret;
+}
+
+static int socfpga_fpga_regulators_on(struct socfpga_fpga_priv *priv)
+{
+ int i, ret;
+
+ for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
+ ret = regulator_enable(priv->fpga_supplies[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static void socfpga_fpga_regulators_power_off(struct socfpga_fpga_priv *priv)
+{
+ int i;
+
+ for (i = SOCFPGA_FPGMGR_NUM_SUPPLIES - 1; i >= 0; i--)
+ regulator_disable(priv->fpga_supplies[i]);
+}
+
+static int socfpga_fpga_regulator_probe(struct platform_device *pdev,
+ struct socfpga_fpga_priv *priv)
+{
+ struct regulator *supply;
+ unsigned int i;
+
+ if (!IS_ENABLED(CONFIG_REGULATOR))
+ return 0;
+
+ for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
+ supply = devm_regulator_get_optional(&pdev->dev,
+ supply_names[i]);
+ if (IS_ERR(supply)) {
+ dev_err(&pdev->dev, "could not get regulators");
+ return -EPROBE_DEFER;
+ }
+ priv->fpga_supplies[i] = supply;
+ }
+
+ return socfpga_fpga_regulators_on(priv);
+}
+
+static int socfpga_fpga_suspend(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+
+ socfpga_fpga_regulators_power_off(priv);
+
+ return 0;
+}
+
+static int socfpga_fpga_resume(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 state;
+ unsigned int timeout;
+ int ret;
+
+ ret = socfpga_fpga_regulators_on(priv);
+ if (ret)
+ return ret;
+
+ for (timeout = 0; timeout < SOCFPGA_RESUME_TIMEOUT; timeout++) {
+ state = socfpga_fpga_state_get(priv);
+ if (state != SOCFPGA_FPGMGR_STAT_POWER_OFF)
+ break;
+ msleep(20);
+ }
+ if (state == SOCFPGA_FPGMGR_STAT_POWER_OFF)
+ return -ETIMEDOUT;
+
+ return ret;
+}
+
+static const struct fpga_manager_ops socfpga_fpga_ops = {
+ .reset = socfpga_fpga_reset,
+ .state = socfpga_fpga_ops_state,
+ .write_init = socfpga_fpga_ops_configure_init,
+ .write = socfpga_fpga_ops_configure_write,
+ .write_complete = socfpga_fpga_ops_configure_complete,
+ .suspend = socfpga_fpga_suspend,
+ .resume = socfpga_fpga_resume,
+};
+
+static int socfpga_fpga_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct socfpga_fpga_priv *priv;
+ struct resource *res;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = socfpga_fpga_regulator_probe(pdev, priv);
+ if (ret)
+ return ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->fpga_base_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->fpga_base_addr))
+ return PTR_ERR(priv->fpga_base_addr);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ priv->fpga_data_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->fpga_data_addr))
+ return PTR_ERR(priv->fpga_base_addr);
+
+ priv->irq = platform_get_irq(pdev, 0);
+ if (priv->irq < 0)
+ return priv->irq;
+
+ ret = devm_request_irq(dev, priv->irq, socfpga_fpga_isr, 0,
+ dev_name(dev), priv);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ return fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager",
+ &socfpga_fpga_ops, priv);
+}
+
+static int socfpga_fpga_remove(struct platform_device *pdev)
+{
+ fpga_mgr_remove(pdev);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id socfpga_fpga_of_match[] = {
+ { .compatible = "altr,fpga-mgr", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, socfpga_fpga_of_match);
+#endif
+
+static struct platform_driver socfpga_fpga_driver = {
+ .probe = socfpga_fpga_probe,
+ .remove = socfpga_fpga_remove,
+ .driver = {
+ .name = "socfpga_fpga_manager",
+ .of_match_table = of_match_ptr(socfpga_fpga_of_match),
+ },
+};
+
+module_platform_driver(socfpga_fpga_driver);
+
+MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_DESCRIPTION("Altera SOCFPGA FPGA Manager");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
WARNING: multiple messages have this Message-ID (diff)
From: <atull@opensource.altera.com>
To: <gregkh@linuxfoundation.org>, <jgunthorpe@obsidianresearch.com>,
<hpa@zytor.com>, <monstr@monstr.eu>, <michal.simek@xilinx.com>,
<rdunlap@infradead.org>
Cc: <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
<pantelis.antoniou@konsulko.com>, <robh+dt@kernel.org>,
<grant.likely@linaro.org>, <iws@ovro.caltech.edu>,
<linux-doc@vger.kernel.org>, <pavel@denx.de>,
<broonie@kernel.org>, <philip@balister.org>, <rubini@gnudd.com>,
<s.trumtrar@pengutronix.de>, <jason@lakedaemon.net>,
<kyle.teske@ni.com>, <nico@linaro.org>, <balbi@ti.com>,
<m.chehab@samsung.com>, <davidb@codeaurora.org>,
<rob@landley.net>, <davem@davemloft.net>, <cesarb@cesarb.net>,
<sameo@linux.intel.com>, <akpm@linux-foundation.org>,
<linus.walleij@linaro.org>, <pawel.moll@arm.com>,
<mark.rutland@arm.com>, <ijc+devicetree@hellion.org.uk>,
<galak@codeaurora.org>, <devel@driverdev.osuosl.org>,
<delicious.quinoa@gmail.com>, <dinguyen@opensource.altera.com>,
<yvanderv@opensource.altera.com>,
Alan Tull <atull@opensource.altera.com>
Subject: [PATCH v6 4/4] staging: fpga manager: add driver for socfpga fpga manager
Date: Thu, 18 Dec 2014 16:29:08 -0600 [thread overview]
Message-ID: <1418941748-16111-5-git-send-email-atull@opensource.altera.com> (raw)
In-Reply-To: <1418941748-16111-1-git-send-email-atull@opensource.altera.com>
From: Alan Tull <atull@opensource.altera.com>
Add driver to fpga manager framework to allow configuration
of FPGA in Altera SoCFPGA parts.
Signed-off-by: Alan Tull <atull@opensource.altera.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
---
v2: fpga_manager struct now contains struct device
fpga_manager_register parameters now take device
v3: skip a version to align versions
v4: move to drivers/staging
v5: fix array_size.cocci warnings
fix platform_no_drv_owner.cocci warnings
Remove .owner = THIS_MODULE
include asm/irq.h
clean up list of includes
use altera_fpga_reset for ops
use enum fpga_mgr_states or u32 as needed
use devm_request_irq
check irq <= 0 instead of == NO_IRQ
Use ARRAY_SIZE
rename altera -> socfpga
static const socfpga_fpga_ops
header moved to linux/fpga/ folder
remove ifdef'ed code
use platform_get_resource and platform_get_irq
move .probe and .remove lines adjacent
use module_platform_driver
use __maybe_unused
only need to 'if (IS_ENABLED(CONFIG_REGULATOR))' in one fn
fix "unsigned 'mode' is never < 0"
v6: return error for (unused) default of case statement
---
drivers/staging/fpga/Kconfig | 5 +
drivers/staging/fpga/Makefile | 1 +
drivers/staging/fpga/socfpga.c | 694 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 700 insertions(+)
create mode 100644 drivers/staging/fpga/socfpga.c
diff --git a/drivers/staging/fpga/Kconfig b/drivers/staging/fpga/Kconfig
index 89ebafc..ce17342 100644
--- a/drivers/staging/fpga/Kconfig
+++ b/drivers/staging/fpga/Kconfig
@@ -19,6 +19,11 @@ config FPGA_MGR_SYSFS
help
FPGA Manager SysFS interface.
+config FPGA_MGR_SOCFPGA
+ tristate "Altera SOCFPGA"
+ help
+ FPGA manager driver support for Altera SOCFPGA.
+
endif # FPGA
endmenu
diff --git a/drivers/staging/fpga/Makefile b/drivers/staging/fpga/Makefile
index 3313c52..ba6c5c5 100644
--- a/drivers/staging/fpga/Makefile
+++ b/drivers/staging/fpga/Makefile
@@ -6,3 +6,4 @@
obj-$(CONFIG_FPGA) += fpga-mgr.o
# FPGA Manager Drivers
+obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o
diff --git a/drivers/staging/fpga/socfpga.c b/drivers/staging/fpga/socfpga.c
new file mode 100644
index 0000000..aa96e43
--- /dev/null
+++ b/drivers/staging/fpga/socfpga.c
@@ -0,0 +1,694 @@
+/*
+ * FPGA Manager Driver for Altera SOCFPGA
+ *
+ * Copyright (C) 2013-2014 Altera Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/pm.h>
+#include <linux/string.h>
+#include <linux/regulator/consumer.h>
+
+/* Register offsets */
+#define SOCFPGA_FPGMGR_STAT_OFST 0x0
+#define SOCFPGA_FPGMGR_CTL_OFST 0x4
+#define SOCFPGA_FPGMGR_DCLKCNT_OFST 0x8
+#define SOCFPGA_FPGMGR_DCLKSTAT_OFST 0xc
+#define SOCFPGA_FPGMGR_GPIO_INTEN_OFST 0x830
+#define SOCFPGA_FPGMGR_GPIO_INTMSK_OFST 0x834
+#define SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST 0x838
+#define SOCFPGA_FPGMGR_GPIO_INT_POL_OFST 0x83c
+#define SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST 0x840
+#define SOCFPGA_FPGMGR_GPIO_RAW_INTSTAT_OFST 0x844
+#define SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST 0x84c
+#define SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST 0x850
+
+/* Register bit defines */
+/* SOCFPGA_FPGMGR_STAT register mode field values */
+#define SOCFPGA_FPGMGR_STAT_POWER_UP 0x0 /*ramping*/
+#define SOCFPGA_FPGMGR_STAT_RESET 0x1
+#define SOCFPGA_FPGMGR_STAT_CFG 0x2
+#define SOCFPGA_FPGMGR_STAT_INIT 0x3
+#define SOCFPGA_FPGMGR_STAT_USER_MODE 0x4
+#define SOCFPGA_FPGMGR_STAT_UNKNOWN 0x5
+#define SOCFPGA_FPGMGR_STAT_STATE_MASK 0x7
+/* This is a flag value that doesn't really happen in this register field */
+#define SOCFPGA_FPGMGR_STAT_POWER_OFF 0x0
+
+#define MSEL_PP16_FAST_NOAES_NODC 0x0
+#define MSEL_PP16_FAST_AES_NODC 0x1
+#define MSEL_PP16_FAST_AESOPT_DC 0x2
+#define MSEL_PP16_SLOW_NOAES_NODC 0x4
+#define MSEL_PP16_SLOW_AES_NODC 0x5
+#define MSEL_PP16_SLOW_AESOPT_DC 0x6
+#define MSEL_PP32_FAST_NOAES_NODC 0x8
+#define MSEL_PP32_FAST_AES_NODC 0x9
+#define MSEL_PP32_FAST_AESOPT_DC 0xa
+#define MSEL_PP32_SLOW_NOAES_NODC 0xc
+#define MSEL_PP32_SLOW_AES_NODC 0xd
+#define MSEL_PP32_SLOW_AESOPT_DC 0xe
+#define SOCFPGA_FPGMGR_STAT_MSEL_MASK 0x000000f8
+#define SOCFPGA_FPGMGR_STAT_MSEL_SHIFT 3
+
+/* SOCFPGA_FPGMGR_CTL register */
+#define SOCFPGA_FPGMGR_CTL_EN 0x00000001
+#define SOCFPGA_FPGMGR_CTL_NCE 0x00000002
+#define SOCFPGA_FPGMGR_CTL_NCFGPULL 0x00000004
+
+#define CDRATIO_X1 0x00000000
+#define CDRATIO_X2 0x00000040
+#define CDRATIO_X4 0x00000080
+#define CDRATIO_X8 0x000000c0
+#define SOCFPGA_FPGMGR_CTL_CDRATIO_MASK 0x000000c0
+
+#define SOCFPGA_FPGMGR_CTL_AXICFGEN 0x00000100
+
+#define CFGWDTH_16 0x00000000
+#define CFGWDTH_32 0x00000200
+#define SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK 0x00000200
+
+/* SOCFPGA_FPGMGR_DCLKSTAT register */
+#define SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE 0x1
+
+/* SOCFPGA_FPGMGR_GPIO_* registers share the same bit positions */
+#define SOCFPGA_FPGMGR_MON_NSTATUS 0x0001
+#define SOCFPGA_FPGMGR_MON_CONF_DONE 0x0002
+#define SOCFPGA_FPGMGR_MON_INIT_DONE 0x0004
+#define SOCFPGA_FPGMGR_MON_CRC_ERROR 0x0008
+#define SOCFPGA_FPGMGR_MON_CVP_CONF_DONE 0x0010
+#define SOCFPGA_FPGMGR_MON_PR_READY 0x0020
+#define SOCFPGA_FPGMGR_MON_PR_ERROR 0x0040
+#define SOCFPGA_FPGMGR_MON_PR_DONE 0x0080
+#define SOCFPGA_FPGMGR_MON_NCONFIG_PIN 0x0100
+#define SOCFPGA_FPGMGR_MON_NSTATUS_PIN 0x0200
+#define SOCFPGA_FPGMGR_MON_CONF_DONE_PIN 0x0400
+#define SOCFPGA_FPGMGR_MON_FPGA_POWER_ON 0x0800
+#define SOCFPGA_FPGMGR_MON_STATUS_MASK 0x0fff
+
+#define SOCFPGA_FPGMGR_NUM_SUPPLIES 3
+#define SOCFPGA_RESUME_TIMEOUT 3
+
+/* In power-up order. Reverse for power-down. */
+static const char *supply_names[SOCFPGA_FPGMGR_NUM_SUPPLIES] __maybe_unused = {
+ "FPGA-1.5V",
+ "FPGA-1.1V",
+ "FPGA-2.5V",
+};
+
+struct socfpga_fpga_priv {
+ void __iomem *fpga_base_addr;
+ void __iomem *fpga_data_addr;
+ struct completion status_complete;
+ int irq;
+ struct regulator *fpga_supplies[SOCFPGA_FPGMGR_NUM_SUPPLIES];
+};
+
+struct cfgmgr_mode {
+ /* Values to set in the CTRL register */
+ u32 ctrl;
+
+ /* flag that this table entry is a valid mode */
+ bool valid;
+};
+
+/* For SOCFPGA_FPGMGR_STAT_MSEL field */
+static struct cfgmgr_mode cfgmgr_modes[] = {
+ [MSEL_PP16_FAST_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
+ [MSEL_PP16_FAST_AES_NODC] = { CFGWDTH_16 | CDRATIO_X2, 1 },
+ [MSEL_PP16_FAST_AESOPT_DC] = { CFGWDTH_16 | CDRATIO_X4, 1 },
+ [MSEL_PP16_SLOW_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
+ [MSEL_PP16_SLOW_AES_NODC] = { CFGWDTH_16 | CDRATIO_X2, 1 },
+ [MSEL_PP16_SLOW_AESOPT_DC] = { CFGWDTH_16 | CDRATIO_X4, 1 },
+ [MSEL_PP32_FAST_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
+ [MSEL_PP32_FAST_AES_NODC] = { CFGWDTH_32 | CDRATIO_X4, 1 },
+ [MSEL_PP32_FAST_AESOPT_DC] = { CFGWDTH_32 | CDRATIO_X8, 1 },
+ [MSEL_PP32_SLOW_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
+ [MSEL_PP32_SLOW_AES_NODC] = { CFGWDTH_32 | CDRATIO_X4, 1 },
+ [MSEL_PP32_SLOW_AESOPT_DC] = { CFGWDTH_32 | CDRATIO_X8, 1 },
+};
+
+static u32 socfpga_fpga_readl(struct socfpga_fpga_priv *priv, u32 reg_offset)
+{
+ return readl(priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_writel(struct socfpga_fpga_priv *priv, u32 reg_offset,
+ u32 value)
+{
+ writel(value, priv->fpga_base_addr + reg_offset);
+}
+
+static u32 socfpga_fpga_raw_readl(struct socfpga_fpga_priv *priv,
+ u32 reg_offset)
+{
+ return __raw_readl(priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_raw_writel(struct socfpga_fpga_priv *priv,
+ u32 reg_offset, u32 value)
+{
+ __raw_writel(value, priv->fpga_base_addr + reg_offset);
+}
+
+static void socfpga_fpga_data_writel(struct socfpga_fpga_priv *priv, u32 value)
+{
+ writel(value, priv->fpga_data_addr);
+}
+
+static inline void socfpga_fpga_set_bitsl(struct socfpga_fpga_priv *priv,
+ u32 offset, u32 bits)
+{
+ u32 val;
+
+ val = socfpga_fpga_readl(priv, offset);
+ val |= bits;
+ socfpga_fpga_writel(priv, offset, val);
+}
+
+static inline void socfpga_fpga_clr_bitsl(struct socfpga_fpga_priv *priv,
+ u32 offset, u32 bits)
+{
+ u32 val;
+
+ val = socfpga_fpga_readl(priv, offset);
+ val &= ~bits;
+ socfpga_fpga_writel(priv, offset, val);
+}
+
+static u32 socfpga_fpga_mon_status_get(struct socfpga_fpga_priv *priv)
+{
+ return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST) &
+ SOCFPGA_FPGMGR_MON_STATUS_MASK;
+}
+
+static u32 socfpga_fpga_state_get(struct socfpga_fpga_priv *priv)
+{
+ u32 status = socfpga_fpga_mon_status_get(priv);
+
+ if ((status & SOCFPGA_FPGMGR_MON_FPGA_POWER_ON) == 0)
+ return SOCFPGA_FPGMGR_STAT_POWER_OFF;
+
+ return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST) &
+ SOCFPGA_FPGMGR_STAT_STATE_MASK;
+}
+
+static void socfpga_fpga_clear_done_status(struct socfpga_fpga_priv *priv)
+{
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST,
+ SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE);
+}
+
+/*
+ * Set the DCLKCNT, wait for DCLKSTAT to report the count completed, and clear
+ * the complete status.
+ */
+static int socfpga_fpga_dclk_set_and_wait_clear(struct socfpga_fpga_priv *priv,
+ u32 count)
+{
+ int timeout = 2;
+ u32 done;
+
+ /* Clear any existing DONE status. */
+ if (socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST))
+ socfpga_fpga_clear_done_status(priv);
+
+ /* Issue the DCLK count. */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKCNT_OFST, count);
+
+ /* Poll DCLKSTAT to see if it completed in the timeout period. */
+ do {
+ done = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST);
+ if (done == SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE) {
+ socfpga_fpga_clear_done_status(priv);
+ return 0;
+ }
+ udelay(1);
+ } while (timeout--);
+
+ return -ETIMEDOUT;
+}
+
+static int socfpga_fpga_wait_for_state(struct socfpga_fpga_priv *priv,
+ u32 state)
+{
+ int timeout = 2;
+
+ /*
+ * HW doesn't support an interrupt for changes in state, so poll to see
+ * if it matches the requested state within the timeout period.
+ */
+ do {
+ if ((socfpga_fpga_state_get(priv) & state) != 0)
+ return 0;
+ msleep(20);
+ } while (timeout--);
+
+ return -ETIMEDOUT;
+}
+
+static void socfpga_fpga_enable_irqs(struct socfpga_fpga_priv *priv, u32 irqs)
+{
+ /* set irqs to level sensitive */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST, 0);
+
+ /* set interrupt polarity */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INT_POL_OFST, irqs);
+
+ /* clear irqs */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
+
+ /* unmask interrupts */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTMSK_OFST, 0);
+
+ /* enable interrupts */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, irqs);
+}
+
+static void socfpga_fpga_disable_irqs(struct socfpga_fpga_priv *priv)
+{
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
+}
+
+static irqreturn_t socfpga_fpga_isr(int irq, void *dev_id)
+{
+ struct socfpga_fpga_priv *priv = dev_id;
+ u32 irqs, st;
+ bool conf_done, nstatus;
+
+ /* clear irqs */
+ irqs = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST);
+
+ socfpga_fpga_raw_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
+
+ st = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST);
+ conf_done = (st & SOCFPGA_FPGMGR_MON_CONF_DONE) != 0;
+ nstatus = (st & SOCFPGA_FPGMGR_MON_NSTATUS) != 0;
+
+ /* success */
+ if (conf_done && nstatus) {
+ /* disable irqs */
+ socfpga_fpga_raw_writel(priv,
+ SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
+ complete(&priv->status_complete);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int socfpga_fpga_wait_for_config_done(struct socfpga_fpga_priv *priv)
+{
+ int timeout, ret = 0;
+
+ socfpga_fpga_disable_irqs(priv);
+ init_completion(&priv->status_complete);
+ socfpga_fpga_enable_irqs(priv, SOCFPGA_FPGMGR_MON_CONF_DONE);
+
+ timeout = wait_for_completion_interruptible_timeout(
+ &priv->status_complete,
+ msecs_to_jiffies(10));
+ if (timeout == 0)
+ ret = -ETIMEDOUT;
+
+ socfpga_fpga_disable_irqs(priv);
+ return ret;
+}
+
+static int socfpga_fpga_cfg_mode_get(struct socfpga_fpga_priv *priv)
+{
+ u32 msel;
+
+ msel = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST);
+ msel &= SOCFPGA_FPGMGR_STAT_MSEL_MASK;
+ msel >>= SOCFPGA_FPGMGR_STAT_MSEL_SHIFT;
+
+ /* Check that this MSEL setting is supported */
+ if ((msel >= ARRAY_SIZE(cfgmgr_modes)) || !cfgmgr_modes[msel].valid)
+ return -EINVAL;
+
+ return msel;
+}
+
+static int socfpga_fpga_cfg_mode_set(struct socfpga_fpga_priv *priv)
+{
+ u32 ctrl_reg;
+ int mode;
+
+ /* get value from MSEL pins */
+ mode = socfpga_fpga_cfg_mode_get(priv);
+ if (mode < 0)
+ return mode;
+
+ /* Adjust CTRL for the CDRATIO */
+ ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CDRATIO_MASK;
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK;
+ ctrl_reg |= cfgmgr_modes[mode].ctrl;
+
+ /* Set NCE to 0. */
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCE;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ return 0;
+}
+
+static int socfpga_fpga_reset(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 ctrl_reg, status;
+ int ret;
+
+ /*
+ * Step 1:
+ * - Set CTRL.CFGWDTH, CTRL.CDRATIO to match cfg mode
+ * - Set CTRL.NCE to 0
+ */
+ ret = socfpga_fpga_cfg_mode_set(priv);
+ if (ret)
+ return ret;
+
+ /* Step 2: Set CTRL.EN to 1 */
+ socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_EN);
+
+ /* Step 3: Set CTRL.NCONFIGPULL to 1 to put FPGA in reset */
+ ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
+ ctrl_reg |= SOCFPGA_FPGMGR_CTL_NCFGPULL;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ /* Step 4: Wait for STATUS.MODE to report FPGA is in reset phase */
+ status = socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_RESET);
+
+ /* Step 5: Set CONTROL.NCONFIGPULL to 0 to release FPGA from reset */
+ ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCFGPULL;
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
+
+ /* Timeout waiting for reset */
+ if (status)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+/*
+ * Prepare the FPGA to receive the configuration data.
+ */
+static int socfpga_fpga_ops_configure_init(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ int ret;
+
+ /* Steps 1 - 5: Reset the FPGA */
+ ret = socfpga_fpga_reset(mgr);
+ if (ret)
+ return ret;
+
+ /* Step 6: Wait for FPGA to enter configuration phase */
+ if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_CFG))
+ return -ETIMEDOUT;
+
+ /* Step 7: Clear nSTATUS interrupt */
+ socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST,
+ SOCFPGA_FPGMGR_MON_NSTATUS);
+
+ /* Step 8: Set CTRL.AXICFGEN to 1 to enable transfer of config data */
+ socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_AXICFGEN);
+
+ return 0;
+}
+
+/*
+ * Step 9: write data to the FPGA data register
+ */
+static int socfpga_fpga_ops_configure_write(struct fpga_manager *mgr,
+ const char *buf, size_t count)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 *buffer_32 = (u32 *)buf;
+ size_t i = 0;
+
+ if (count <= 0)
+ return -EINVAL;
+
+ /* Write out the complete 32-bit chunks. */
+ while (count >= sizeof(u32)) {
+ socfpga_fpga_data_writel(priv, buffer_32[i++]);
+ count -= sizeof(u32);
+ }
+
+ /* Write out remaining non 32-bit chunks. */
+ switch (count) {
+ case 3:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x00ffffff);
+ break;
+ case 2:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x0000ffff);
+ break;
+ case 1:
+ socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x000000ff);
+ break;
+ case 0:
+ break;
+ default:
+ /* This will never happen. */
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+static int socfpga_fpga_ops_configure_complete(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 status;
+
+ /*
+ * Step 10:
+ * - Observe CONF_DONE and nSTATUS (active low)
+ * - if CONF_DONE = 1 and nSTATUS = 1, configuration was successful
+ * - if CONF_DONE = 0 and nSTATUS = 0, configuration failed
+ */
+ status = socfpga_fpga_wait_for_config_done(priv);
+ if (status)
+ return status;
+
+ /* Step 11: Clear CTRL.AXICFGEN to disable transfer of config data */
+ socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_AXICFGEN);
+
+ /*
+ * Step 12:
+ * - Write 4 to DCLKCNT
+ * - Wait for STATUS.DCNTDONE = 1
+ * - Clear W1C bit in STATUS.DCNTDONE
+ */
+ if (socfpga_fpga_dclk_set_and_wait_clear(priv, 4))
+ return -ETIMEDOUT;
+
+ /* Step 13: Wait for STATUS.MODE to report USER MODE */
+ if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_USER_MODE))
+ return -ETIMEDOUT;
+
+ /* Step 14: Set CTRL.EN to 0 */
+ socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
+ SOCFPGA_FPGMGR_CTL_EN);
+
+ return 0;
+}
+
+/* Translate state register values to FPGA framework state */
+static const enum fpga_mgr_states socfpga_state_to_framework_state[] = {
+ [SOCFPGA_FPGMGR_STAT_POWER_OFF] = FPGA_MGR_STATE_POWER_OFF,
+ [SOCFPGA_FPGMGR_STAT_RESET] = FPGA_MGR_STATE_RESET,
+ [SOCFPGA_FPGMGR_STAT_CFG] = FPGA_MGR_STATE_WRITE_INIT,
+ [SOCFPGA_FPGMGR_STAT_INIT] = FPGA_MGR_STATE_WRITE_INIT,
+ [SOCFPGA_FPGMGR_STAT_USER_MODE] = FPGA_MGR_STATE_OPERATING,
+ [SOCFPGA_FPGMGR_STAT_UNKNOWN] = FPGA_MGR_STATE_UNKNOWN,
+};
+
+static enum fpga_mgr_states socfpga_fpga_ops_state(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ enum fpga_mgr_states ret;
+ u32 state;
+
+ state = socfpga_fpga_state_get(priv);
+
+ if (state < ARRAY_SIZE(socfpga_state_to_framework_state))
+ ret = socfpga_state_to_framework_state[state];
+ else
+ ret = FPGA_MGR_STATE_UNKNOWN;
+
+ return ret;
+}
+
+static int socfpga_fpga_regulators_on(struct socfpga_fpga_priv *priv)
+{
+ int i, ret;
+
+ for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
+ ret = regulator_enable(priv->fpga_supplies[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static void socfpga_fpga_regulators_power_off(struct socfpga_fpga_priv *priv)
+{
+ int i;
+
+ for (i = SOCFPGA_FPGMGR_NUM_SUPPLIES - 1; i >= 0; i--)
+ regulator_disable(priv->fpga_supplies[i]);
+}
+
+static int socfpga_fpga_regulator_probe(struct platform_device *pdev,
+ struct socfpga_fpga_priv *priv)
+{
+ struct regulator *supply;
+ unsigned int i;
+
+ if (!IS_ENABLED(CONFIG_REGULATOR))
+ return 0;
+
+ for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
+ supply = devm_regulator_get_optional(&pdev->dev,
+ supply_names[i]);
+ if (IS_ERR(supply)) {
+ dev_err(&pdev->dev, "could not get regulators");
+ return -EPROBE_DEFER;
+ }
+ priv->fpga_supplies[i] = supply;
+ }
+
+ return socfpga_fpga_regulators_on(priv);
+}
+
+static int socfpga_fpga_suspend(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+
+ socfpga_fpga_regulators_power_off(priv);
+
+ return 0;
+}
+
+static int socfpga_fpga_resume(struct fpga_manager *mgr)
+{
+ struct socfpga_fpga_priv *priv = mgr->priv;
+ u32 state;
+ unsigned int timeout;
+ int ret;
+
+ ret = socfpga_fpga_regulators_on(priv);
+ if (ret)
+ return ret;
+
+ for (timeout = 0; timeout < SOCFPGA_RESUME_TIMEOUT; timeout++) {
+ state = socfpga_fpga_state_get(priv);
+ if (state != SOCFPGA_FPGMGR_STAT_POWER_OFF)
+ break;
+ msleep(20);
+ }
+ if (state == SOCFPGA_FPGMGR_STAT_POWER_OFF)
+ return -ETIMEDOUT;
+
+ return ret;
+}
+
+static const struct fpga_manager_ops socfpga_fpga_ops = {
+ .reset = socfpga_fpga_reset,
+ .state = socfpga_fpga_ops_state,
+ .write_init = socfpga_fpga_ops_configure_init,
+ .write = socfpga_fpga_ops_configure_write,
+ .write_complete = socfpga_fpga_ops_configure_complete,
+ .suspend = socfpga_fpga_suspend,
+ .resume = socfpga_fpga_resume,
+};
+
+static int socfpga_fpga_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct socfpga_fpga_priv *priv;
+ struct resource *res;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = socfpga_fpga_regulator_probe(pdev, priv);
+ if (ret)
+ return ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->fpga_base_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->fpga_base_addr))
+ return PTR_ERR(priv->fpga_base_addr);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ priv->fpga_data_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->fpga_data_addr))
+ return PTR_ERR(priv->fpga_base_addr);
+
+ priv->irq = platform_get_irq(pdev, 0);
+ if (priv->irq < 0)
+ return priv->irq;
+
+ ret = devm_request_irq(dev, priv->irq, socfpga_fpga_isr, 0,
+ dev_name(dev), priv);
+ if (IS_ERR_VALUE(ret))
+ return ret;
+
+ return fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager",
+ &socfpga_fpga_ops, priv);
+}
+
+static int socfpga_fpga_remove(struct platform_device *pdev)
+{
+ fpga_mgr_remove(pdev);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id socfpga_fpga_of_match[] = {
+ { .compatible = "altr,fpga-mgr", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, socfpga_fpga_of_match);
+#endif
+
+static struct platform_driver socfpga_fpga_driver = {
+ .probe = socfpga_fpga_probe,
+ .remove = socfpga_fpga_remove,
+ .driver = {
+ .name = "socfpga_fpga_manager",
+ .of_match_table = of_match_ptr(socfpga_fpga_of_match),
+ },
+};
+
+module_platform_driver(socfpga_fpga_driver);
+
+MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_DESCRIPTION("Altera SOCFPGA FPGA Manager");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
next prev parent reply other threads:[~2014-12-18 22:29 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-18 22:29 [PATCH v6 0/4] FPGA Manager Framework atull
2014-12-18 22:29 ` atull
2014-12-18 22:29 ` [PATCH v6 1/4] doc: add bindings document for altera fpga manager atull
2014-12-18 22:29 ` atull
2014-12-18 22:29 ` [PATCH v6 2/4] fpga manager: add sysfs interface document atull
2014-12-18 22:29 ` atull
2014-12-18 22:29 ` [PATCH v6 3/4] staging: fpga manager: framework core atull
2014-12-18 22:29 ` atull
2014-12-19 14:08 ` Michal Simek
2014-12-19 14:08 ` Michal Simek
2014-12-18 22:29 ` atull [this message]
2014-12-18 22:29 ` [PATCH v6 4/4] staging: fpga manager: add driver for socfpga fpga manager atull
2014-12-19 8:55 ` Steffen Trumtrar
2014-12-19 14:05 ` Michal Simek
2014-12-19 14:05 ` Michal Simek
2014-12-19 15:07 ` Steffen Trumtrar
2014-12-19 15:55 ` atull
2014-12-19 15:55 ` atull
2014-12-19 16:15 ` Steffen Trumtrar
2014-12-19 14:20 ` [PATCH v6 0/4] FPGA Manager Framework Michal Simek
2014-12-19 14:20 ` Michal Simek
2014-12-19 15:38 ` Greg KH
2014-12-19 15:38 ` Greg KH
2014-12-19 15:47 ` atull
2014-12-19 15:47 ` atull
2014-12-19 16:49 ` Greg KH
2014-12-19 16:49 ` Greg KH
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1418941748-16111-5-git-send-email-atull@opensource.altera.com \
--to=atull@opensource.altera.com \
--cc=akpm@linux-foundation.org \
--cc=balbi@ti.com \
--cc=broonie@kernel.org \
--cc=cesarb@cesarb.net \
--cc=davem@davemloft.net \
--cc=davidb@codeaurora.org \
--cc=delicious.quinoa@gmail.com \
--cc=devel@driverdev.osuosl.org \
--cc=devicetree@vger.kernel.org \
--cc=dinguyen@opensource.altera.com \
--cc=galak@codeaurora.org \
--cc=grant.likely@linaro.org \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=ijc+devicetree@hellion.org.uk \
--cc=iws@ovro.caltech.edu \
--cc=jason@lakedaemon.net \
--cc=jgunthorpe@obsidianresearch.com \
--cc=kyle.teske@ni.com \
--cc=linus.walleij@linaro.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=m.chehab@samsung.com \
--cc=mark.rutland@arm.com \
--cc=michal.simek@xilinx.com \
--cc=monstr@monstr.eu \
--cc=nico@linaro.org \
--cc=pantelis.antoniou@konsulko.com \
--cc=pavel@denx.de \
--cc=pawel.moll@arm.com \
--cc=philip@balister.org \
--cc=rdunlap@infradead.org \
--cc=rob@landley.net \
--cc=robh+dt@kernel.org \
--cc=rubini@gnudd.com \
--cc=s.trumtrar@pengutronix.de \
--cc=sameo@linux.intel.com \
--cc=yvanderv@opensource.altera.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.