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-rw-r--r--drivers/soc/pxa/mfp.c282
1 files changed, 282 insertions, 0 deletions
diff --git a/drivers/soc/pxa/mfp.c b/drivers/soc/pxa/mfp.c
new file mode 100644
index 0000000000..6220ba321c
--- /dev/null
+++ b/drivers/soc/pxa/mfp.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/arm/plat-pxa/mfp.c
+ *
+ * Multi-Function Pin Support
+ *
+ * Copyright (C) 2007 Marvell Internation Ltd.
+ *
+ * 2007-08-21: eric miao <eric.miao@marvell.com>
+ * initial version
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+
+#include <linux/soc/pxa/mfp.h>
+
+#define MFPR_SIZE (PAGE_SIZE)
+
+/* MFPR register bit definitions */
+#define MFPR_PULL_SEL (0x1 << 15)
+#define MFPR_PULLUP_EN (0x1 << 14)
+#define MFPR_PULLDOWN_EN (0x1 << 13)
+#define MFPR_SLEEP_SEL (0x1 << 9)
+#define MFPR_SLEEP_OE_N (0x1 << 7)
+#define MFPR_EDGE_CLEAR (0x1 << 6)
+#define MFPR_EDGE_FALL_EN (0x1 << 5)
+#define MFPR_EDGE_RISE_EN (0x1 << 4)
+
+#define MFPR_SLEEP_DATA(x) ((x) << 8)
+#define MFPR_DRIVE(x) (((x) & 0x7) << 10)
+#define MFPR_AF_SEL(x) (((x) & 0x7) << 0)
+
+#define MFPR_EDGE_NONE (0)
+#define MFPR_EDGE_RISE (MFPR_EDGE_RISE_EN)
+#define MFPR_EDGE_FALL (MFPR_EDGE_FALL_EN)
+#define MFPR_EDGE_BOTH (MFPR_EDGE_RISE | MFPR_EDGE_FALL)
+
+/*
+ * Table that determines the low power modes outputs, with actual settings
+ * used in parentheses for don't-care values. Except for the float output,
+ * the configured driven and pulled levels match, so if there is a need for
+ * non-LPM pulled output, the same configuration could probably be used.
+ *
+ * Output value sleep_oe_n sleep_data pullup_en pulldown_en pull_sel
+ * (bit 7) (bit 8) (bit 14) (bit 13) (bit 15)
+ *
+ * Input 0 X(0) X(0) X(0) 0
+ * Drive 0 0 0 0 X(1) 0
+ * Drive 1 0 1 X(1) 0 0
+ * Pull hi (1) 1 X(1) 1 0 0
+ * Pull lo (0) 1 X(0) 0 1 0
+ * Z (float) 1 X(0) 0 0 0
+ */
+#define MFPR_LPM_INPUT (0)
+#define MFPR_LPM_DRIVE_LOW (MFPR_SLEEP_DATA(0) | MFPR_PULLDOWN_EN)
+#define MFPR_LPM_DRIVE_HIGH (MFPR_SLEEP_DATA(1) | MFPR_PULLUP_EN)
+#define MFPR_LPM_PULL_LOW (MFPR_LPM_DRIVE_LOW | MFPR_SLEEP_OE_N)
+#define MFPR_LPM_PULL_HIGH (MFPR_LPM_DRIVE_HIGH | MFPR_SLEEP_OE_N)
+#define MFPR_LPM_FLOAT (MFPR_SLEEP_OE_N)
+#define MFPR_LPM_MASK (0xe080)
+
+/*
+ * The pullup and pulldown state of the MFP pin at run mode is by default
+ * determined by the selected alternate function. In case that some buggy
+ * devices need to override this default behavior, the definitions below
+ * indicates the setting of corresponding MFPR bits
+ *
+ * Definition pull_sel pullup_en pulldown_en
+ * MFPR_PULL_NONE 0 0 0
+ * MFPR_PULL_LOW 1 0 1
+ * MFPR_PULL_HIGH 1 1 0
+ * MFPR_PULL_BOTH 1 1 1
+ * MFPR_PULL_FLOAT 1 0 0
+ */
+#define MFPR_PULL_NONE (0)
+#define MFPR_PULL_LOW (MFPR_PULL_SEL | MFPR_PULLDOWN_EN)
+#define MFPR_PULL_BOTH (MFPR_PULL_LOW | MFPR_PULLUP_EN)
+#define MFPR_PULL_HIGH (MFPR_PULL_SEL | MFPR_PULLUP_EN)
+#define MFPR_PULL_FLOAT (MFPR_PULL_SEL)
+
+/* mfp_spin_lock is used to ensure that MFP register configuration
+ * (most likely a read-modify-write operation) is atomic, and that
+ * mfp_table[] is consistent
+ */
+static DEFINE_SPINLOCK(mfp_spin_lock);
+
+static void __iomem *mfpr_mmio_base;
+
+struct mfp_pin {
+ unsigned long config; /* -1 for not configured */
+ unsigned long mfpr_off; /* MFPRxx Register offset */
+ unsigned long mfpr_run; /* Run-Mode Register Value */
+ unsigned long mfpr_lpm; /* Low Power Mode Register Value */
+};
+
+static struct mfp_pin mfp_table[MFP_PIN_MAX];
+
+/* mapping of MFP_LPM_* definitions to MFPR_LPM_* register bits */
+static const unsigned long mfpr_lpm[] = {
+ MFPR_LPM_INPUT,
+ MFPR_LPM_DRIVE_LOW,
+ MFPR_LPM_DRIVE_HIGH,
+ MFPR_LPM_PULL_LOW,
+ MFPR_LPM_PULL_HIGH,
+ MFPR_LPM_FLOAT,
+ MFPR_LPM_INPUT,
+};
+
+/* mapping of MFP_PULL_* definitions to MFPR_PULL_* register bits */
+static const unsigned long mfpr_pull[] = {
+ MFPR_PULL_NONE,
+ MFPR_PULL_LOW,
+ MFPR_PULL_HIGH,
+ MFPR_PULL_BOTH,
+ MFPR_PULL_FLOAT,
+};
+
+/* mapping of MFP_LPM_EDGE_* definitions to MFPR_EDGE_* register bits */
+static const unsigned long mfpr_edge[] = {
+ MFPR_EDGE_NONE,
+ MFPR_EDGE_RISE,
+ MFPR_EDGE_FALL,
+ MFPR_EDGE_BOTH,
+};
+
+#define mfpr_readl(off) \
+ __raw_readl(mfpr_mmio_base + (off))
+
+#define mfpr_writel(off, val) \
+ __raw_writel(val, mfpr_mmio_base + (off))
+
+#define mfp_configured(p) ((p)->config != -1)
+
+/*
+ * perform a read-back of any valid MFPR register to make sure the
+ * previous writings are finished
+ */
+static unsigned long mfpr_off_readback;
+#define mfpr_sync() (void)__raw_readl(mfpr_mmio_base + mfpr_off_readback)
+
+static inline void __mfp_config_run(struct mfp_pin *p)
+{
+ if (mfp_configured(p))
+ mfpr_writel(p->mfpr_off, p->mfpr_run);
+}
+
+static inline void __mfp_config_lpm(struct mfp_pin *p)
+{
+ if (mfp_configured(p)) {
+ unsigned long mfpr_clr = (p->mfpr_run & ~MFPR_EDGE_BOTH) | MFPR_EDGE_CLEAR;
+ if (mfpr_clr != p->mfpr_run)
+ mfpr_writel(p->mfpr_off, mfpr_clr);
+ if (p->mfpr_lpm != mfpr_clr)
+ mfpr_writel(p->mfpr_off, p->mfpr_lpm);
+ }
+}
+
+void mfp_config(unsigned long *mfp_cfgs, int num)
+{
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+
+ for (i = 0; i < num; i++, mfp_cfgs++) {
+ unsigned long tmp, c = *mfp_cfgs;
+ struct mfp_pin *p;
+ int pin, af, drv, lpm, edge, pull;
+
+ pin = MFP_PIN(c);
+ BUG_ON(pin >= MFP_PIN_MAX);
+ p = &mfp_table[pin];
+
+ af = MFP_AF(c);
+ drv = MFP_DS(c);
+ lpm = MFP_LPM_STATE(c);
+ edge = MFP_LPM_EDGE(c);
+ pull = MFP_PULL(c);
+
+ /* run-mode pull settings will conflict with MFPR bits of
+ * low power mode state, calculate mfpr_run and mfpr_lpm
+ * individually if pull != MFP_PULL_NONE
+ */
+ tmp = MFPR_AF_SEL(af) | MFPR_DRIVE(drv);
+
+ if (likely(pull == MFP_PULL_NONE)) {
+ p->mfpr_run = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
+ p->mfpr_lpm = p->mfpr_run;
+ } else {
+ p->mfpr_lpm = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
+ p->mfpr_run = tmp | mfpr_pull[pull];
+ }
+
+ p->config = c; __mfp_config_run(p);
+ }
+
+ mfpr_sync();
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+unsigned long mfp_read(int mfp)
+{
+ unsigned long val, flags;
+
+ BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+ val = mfpr_readl(mfp_table[mfp].mfpr_off);
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+
+ return val;
+}
+
+void mfp_write(int mfp, unsigned long val)
+{
+ unsigned long flags;
+
+ BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+ mfpr_writel(mfp_table[mfp].mfpr_off, val);
+ mfpr_sync();
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+void __init mfp_init_base(void __iomem *mfpr_base)
+{
+ int i;
+
+ /* initialize the table with default - unconfigured */
+ for (i = 0; i < ARRAY_SIZE(mfp_table); i++)
+ mfp_table[i].config = -1;
+
+ mfpr_mmio_base = mfpr_base;
+}
+
+void __init mfp_init_addr(struct mfp_addr_map *map)
+{
+ struct mfp_addr_map *p;
+ unsigned long offset, flags;
+ int i;
+
+ spin_lock_irqsave(&mfp_spin_lock, flags);
+
+ /* mfp offset for readback */
+ mfpr_off_readback = map[0].offset;
+
+ for (p = map; p->start != MFP_PIN_INVALID; p++) {
+ offset = p->offset;
+ i = p->start;
+
+ do {
+ mfp_table[i].mfpr_off = offset;
+ mfp_table[i].mfpr_run = 0;
+ mfp_table[i].mfpr_lpm = 0;
+ offset += 4; i++;
+ } while ((i <= p->end) && (p->end != -1));
+ }
+
+ spin_unlock_irqrestore(&mfp_spin_lock, flags);
+}
+
+void mfp_config_lpm(void)
+{
+ struct mfp_pin *p = &mfp_table[0];
+ int pin;
+
+ for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
+ __mfp_config_lpm(p);
+}
+
+void mfp_config_run(void)
+{
+ struct mfp_pin *p = &mfp_table[0];
+ int pin;
+
+ for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
+ __mfp_config_run(p);
+}