[RFC PATCH 01/10] CHROMIUM: cros_ec: Remove cros_ec dependency in lpc_mec
From: Nick Crews
Date: Fri Dec 14 2018 - 19:19:49 EST
From: Duncan Laurie <dlaurie@xxxxxxxxxx>
In order to allow this code to be re-used, remove the dependency
on the rest of the cros_ec code from the cros_ec_lpc_mec functions.
Instead of using a hardcoded register base address of 0x800 have
this be passed in to cros_ec_lpc_mec_init(). The existing cros_ec
use case now passes in the 0x800 base address this way.
Signed-off-by: Duncan Laurie <dlaurie@xxxxxxxxxx>
Signed-off-by: Nick Crews <ncrews@xxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_lpc_mec.c | 54 +++++++++++++++++++----
drivers/platform/chrome/cros_ec_lpc_mec.h | 45 +++++++++++--------
drivers/platform/chrome/cros_ec_lpc_reg.c | 43 +++++-------------
3 files changed, 85 insertions(+), 57 deletions(-)
diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.c b/drivers/platform/chrome/cros_ec_lpc_mec.c
index c4edfa83e493..18bd9f82be6c 100644
--- a/drivers/platform/chrome/cros_ec_lpc_mec.c
+++ b/drivers/platform/chrome/cros_ec_lpc_mec.c
@@ -24,6 +24,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mfd/cros_ec_commands.h>
+#include <linux/mfd/cros_ec_lpc_mec.h>
#include <linux/mutex.h>
#include <linux/types.h>
@@ -34,6 +35,7 @@
* EC mutex because memmap data may be accessed without it being held.
*/
static struct mutex io_mutex;
+static u16 mec_emi_base, mec_emi_end;
/*
* cros_ec_lpc_mec_emi_write_address
@@ -46,10 +48,39 @@ static struct mutex io_mutex;
static void cros_ec_lpc_mec_emi_write_address(u16 addr,
enum cros_ec_lpc_mec_emi_access_mode access_type)
{
- /* Address relative to start of EMI range */
- addr -= MEC_EMI_RANGE_START;
- outb((addr & 0xfc) | access_type, MEC_EMI_EC_ADDRESS_B0);
- outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1);
+ outb((addr & 0xfc) | access_type, MEC_EMI_EC_ADDRESS_B0(mec_emi_base));
+ outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1(mec_emi_base));
+}
+
+/*
+ * cros_ec_lpc_mec_in_range
+ *
+ * Determine if requested addresses are in MEC EMI range.
+ *
+ * @offset: Address offset
+ * @length: Number of bytes to check
+ *
+ * @return 1 if in range, 0 if not, and -1 if there is an error
+ * such as the mec range not being initialized
+ */
+int cros_ec_lpc_mec_in_range(unsigned int offset, unsigned int length)
+{
+ if (length == 0)
+ return -1;
+
+ if (WARN_ON(mec_emi_base == 0 || mec_emi_end == 0))
+ return -1;
+
+ if (offset >= mec_emi_base && offset < mec_emi_end) {
+ if (WARN_ON(offset + length - 1 <= mec_emi_end))
+ return -1;
+ return 1;
+ }
+
+ if (WARN_ON(offset + length > mec_emi_base && offset < mec_emi_end))
+ return -1;
+
+ return 0;
}
/*
@@ -71,6 +102,11 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
u8 sum = 0;
enum cros_ec_lpc_mec_emi_access_mode access, new_access;
+ /* Return checksum of 0 if window is not initialized */
+ WARN_ON(mec_emi_base == 0 || mec_emi_end == 0);
+ if (mec_emi_base == 0 || mec_emi_end == 0)
+ return 0;
+
/*
* Long access cannot be used on misaligned data since reading B0 loads
* the data register and writing B3 flushes.
@@ -86,9 +122,9 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
cros_ec_lpc_mec_emi_write_address(offset, access);
/* Skip bytes in case of misaligned offset */
- io_addr = MEC_EMI_EC_DATA_B0 + (offset & 0x3);
+ io_addr = MEC_EMI_EC_DATA_B0(mec_emi_base) + (offset & 0x3);
while (i < length) {
- while (io_addr <= MEC_EMI_EC_DATA_B3) {
+ while (io_addr <= MEC_EMI_EC_DATA_B3(mec_emi_base)) {
if (io_type == MEC_IO_READ)
buf[i] = inb(io_addr++);
else
@@ -118,7 +154,7 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
}
/* Access [B0, B3] on each loop pass */
- io_addr = MEC_EMI_EC_DATA_B0;
+ io_addr = MEC_EMI_EC_DATA_B0(mec_emi_base);
}
done:
@@ -128,9 +164,11 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
}
EXPORT_SYMBOL(cros_ec_lpc_io_bytes_mec);
-void cros_ec_lpc_mec_init(void)
+void cros_ec_lpc_mec_init(unsigned int base, unsigned int end)
{
mutex_init(&io_mutex);
+ mec_emi_base = base;
+ mec_emi_end = end;
}
EXPORT_SYMBOL(cros_ec_lpc_mec_init);
diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.h b/drivers/platform/chrome/cros_ec_lpc_mec.h
index 105068c0e919..a81cc6a8b621 100644
--- a/drivers/platform/chrome/cros_ec_lpc_mec.h
+++ b/drivers/platform/chrome/cros_ec_lpc_mec.h
@@ -24,8 +24,6 @@
#ifndef __CROS_EC_LPC_MEC_H
#define __CROS_EC_LPC_MEC_H
-#include <linux/mfd/cros_ec_commands.h>
-
enum cros_ec_lpc_mec_emi_access_mode {
/* 8-bit access */
ACCESS_TYPE_BYTE = 0x0,
@@ -45,35 +43,46 @@ enum cros_ec_lpc_mec_io_type {
MEC_IO_WRITE,
};
-/* Access IO ranges 0x800 thru 0x9ff using EMI interface instead of LPC */
-#define MEC_EMI_RANGE_START EC_HOST_CMD_REGION0
-#define MEC_EMI_RANGE_END (EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE)
-
/* EMI registers are relative to base */
-#define MEC_EMI_BASE 0x800
-#define MEC_EMI_HOST_TO_EC (MEC_EMI_BASE + 0)
-#define MEC_EMI_EC_TO_HOST (MEC_EMI_BASE + 1)
-#define MEC_EMI_EC_ADDRESS_B0 (MEC_EMI_BASE + 2)
-#define MEC_EMI_EC_ADDRESS_B1 (MEC_EMI_BASE + 3)
-#define MEC_EMI_EC_DATA_B0 (MEC_EMI_BASE + 4)
-#define MEC_EMI_EC_DATA_B1 (MEC_EMI_BASE + 5)
-#define MEC_EMI_EC_DATA_B2 (MEC_EMI_BASE + 6)
-#define MEC_EMI_EC_DATA_B3 (MEC_EMI_BASE + 7)
+#define MEC_EMI_HOST_TO_EC(MEC_EMI_BASE) (MEC_EMI_BASE + 0)
+#define MEC_EMI_EC_TO_HOST(MEC_EMI_BASE) (MEC_EMI_BASE + 1)
+#define MEC_EMI_EC_ADDRESS_B0(MEC_EMI_BASE) (MEC_EMI_BASE + 2)
+#define MEC_EMI_EC_ADDRESS_B1(MEC_EMI_BASE) (MEC_EMI_BASE + 3)
+#define MEC_EMI_EC_DATA_B0(MEC_EMI_BASE) (MEC_EMI_BASE + 4)
+#define MEC_EMI_EC_DATA_B1(MEC_EMI_BASE) (MEC_EMI_BASE + 5)
+#define MEC_EMI_EC_DATA_B2(MEC_EMI_BASE) (MEC_EMI_BASE + 6)
+#define MEC_EMI_EC_DATA_B3(MEC_EMI_BASE) (MEC_EMI_BASE + 7)
-/*
+/**
* cros_ec_lpc_mec_init
*
* Initialize MEC I/O.
+ *
+ * @base: MEC EMI Base address
+ * @end: MEC EMI End address
*/
-void cros_ec_lpc_mec_init(void);
+void cros_ec_lpc_mec_init(unsigned int base, unsigned int end);
-/*
+/**
* cros_ec_lpc_mec_destroy
*
* Cleanup MEC I/O.
*/
void cros_ec_lpc_mec_destroy(void);
+/**
+ * cros_ec_lpc_mec_in_range
+ *
+ * Determine if requested addresses are in MEC EMI range.
+ *
+ * @offset: Address offset
+ * @length: Number of bytes to check
+ *
+ * @return 1 if in range, 0 if not, and -1 if there is an error
+ * such as the mec range not being initialized
+ */
+int cros_ec_lpc_mec_in_range(unsigned int offset, unsigned int length);
+
/**
* cros_ec_lpc_io_bytes_mec - Read / write bytes to MEC EMI port
*
diff --git a/drivers/platform/chrome/cros_ec_lpc_reg.c b/drivers/platform/chrome/cros_ec_lpc_reg.c
index fc23d535c404..4cba259b5b1e 100644
--- a/drivers/platform/chrome/cros_ec_lpc_reg.c
+++ b/drivers/platform/chrome/cros_ec_lpc_reg.c
@@ -59,51 +59,32 @@ static u8 lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
{
- if (length == 0)
- return 0;
-
- /* Access desired range through EMI interface */
- if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) {
- /* Ensure we don't straddle EMI region */
- if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END))
- return 0;
+ int in_range = cros_ec_lpc_mec_in_range(offset, length);
- return cros_ec_lpc_io_bytes_mec(MEC_IO_READ, offset, length,
- dest);
- }
-
- if (WARN_ON(offset + length > MEC_EMI_RANGE_START &&
- offset < MEC_EMI_RANGE_START))
+ if (in_range < 0)
return 0;
- return lpc_read_bytes(offset, length, dest);
+ return in_range ?
+ cros_ec_lpc_io_bytes_mec(MEC_IO_READ, offset, length, dest) :
+ lpc_read_bytes(offset, length, dest);
}
u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
{
- if (length == 0)
- return 0;
-
- /* Access desired range through EMI interface */
- if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) {
- /* Ensure we don't straddle EMI region */
- if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END))
- return 0;
+ int in_range = cros_ec_lpc_mec_in_range(offset, length);
- return cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, offset, length,
- msg);
- }
-
- if (WARN_ON(offset + length > MEC_EMI_RANGE_START &&
- offset < MEC_EMI_RANGE_START))
+ if (in_range < 0)
return 0;
- return lpc_write_bytes(offset, length, msg);
+ return in_range ?
+ cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, offset, length, msg) :
+ lpc_write_bytes(offset, length, msg);
}
void cros_ec_lpc_reg_init(void)
{
- cros_ec_lpc_mec_init();
+ cros_ec_lpc_mec_init(EC_HOST_CMD_REGION0,
+ EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE);
}
void cros_ec_lpc_reg_destroy(void)
--
2.20.0.405.gbc1bbc6f85-goog