New patch to review for coreboot: intel/fsp_baytrail: Switch to using read32() and write32() in i2c.c
Ben Gardner (gardner.ben@gmail.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/14162
-gerrit
commit 25e898834cc2cf2d136189fe579cf2a3fecb8f48 Author: Ben Gardner gardner.ben@gmail.com Date: Wed Mar 23 10:11:24 2016 -0500
intel/fsp_baytrail: Switch to using read32() and write32() in i2c.c
i2c.c uses "*(volatile unsigned int *)" constructs where it could use read32() and write32(). Switch to using read32() and write32().
The remaining instances in wait_tx_fifo() and wait_rx_fifo() are fixed in https://review.coreboot.org/#/c/14160/
I also fixed a few minor white space issues.
Change-Id: I587551272ac171ef1f42c7eb26daf877dc56646b Signed-off-by: Ben Gardner gardner.ben@gmail.com --- src/soc/intel/fsp_baytrail/i2c.c | 47 ++++++++++++++++++++-------------------- 1 file changed, 24 insertions(+), 23 deletions(-)
diff --git a/src/soc/intel/fsp_baytrail/i2c.c b/src/soc/intel/fsp_baytrail/i2c.c index c6c8f65..5a0d59d 100644 --- a/src/soc/intel/fsp_baytrail/i2c.c +++ b/src/soc/intel/fsp_baytrail/i2c.c @@ -23,7 +23,8 @@ /* Wait for the transmit FIFO till there is at least one slot empty. * FIFO stall due to transmit abort will be checked and resolved */ -static int wait_tx_fifo(char *base_adr) { +static int wait_tx_fifo(char *base_adr) +{ int i;
if (read32(base_adr + I2C_ABORT_SOURCE) & 0x1ffff) { @@ -35,7 +36,7 @@ static int wait_tx_fifo(char *base_adr) {
/* Wait here for a free slot in TX-FIFO */ i = I2C_TIMEOUT_US; - while ((!(*((volatile unsigned int *)(base_adr + I2C_STATUS)) & I2C_TFNF))) { + while (!(read32(base_adr + I2C_STATUS) & I2C_TFNF)) { udelay(1); if (!--i) return I2C_ERR_TIMEOUT; @@ -47,7 +48,8 @@ static int wait_tx_fifo(char *base_adr) { /* Wait for the receive FIFO till there is at least one valid entry to read. * FIFO stall due to transmit abort will be checked and resolved */ -static int wait_rx_fifo(char *base_adr) { +static int wait_rx_fifo(char *base_adr) +{ int i; if (read32(base_adr + I2C_ABORT_SOURCE) & 0x1ffff) { /* Reading back I2C_CLR_TX_ABRT resets abort lock on TX FIFO */ @@ -58,7 +60,7 @@ static int wait_rx_fifo(char *base_adr) {
/* Wait here for a received entry in RX-FIFO */ i = I2C_TIMEOUT_US; - while ((!(*((volatile unsigned int *)(base_adr + I2C_STATUS)) & I2C_RFNE))) { + while (!(read32(base_adr + I2C_STATUS) & I2C_RFNE)) { udelay(1); if (!--i) return I2C_ERR_TIMEOUT; @@ -74,20 +76,19 @@ static int wait_rx_fifo(char *base_adr) { static int wait_for_idle(char *base_adr) { int i; - volatile int status; + int status;
/* For IDLE, increase timeout by ten times */ i = I2C_TIMEOUT_US * 10; - status = *((volatile unsigned int *)(base_adr + I2C_STATUS)); + status = read32(base_adr + I2C_STATUS); while (((status & I2C_MST_ACTIVITY) || (!(status & I2C_TFE)))) { - status = *((volatile unsigned int *)(base_adr + I2C_STATUS)); + status = read32(base_adr + I2C_STATUS); udelay(1); if (!--i) return I2C_ERR_TIMEOUT; }
return I2C_SUCCESS; - }
/** \brief Enables I2C-controller, sets up BAR and timing parameters @@ -101,6 +102,7 @@ int i2c_init(unsigned bus) I2C3_MEM_BASE, I2C4_MEM_BASE, I2C5_MEM_BASE, I2C6_MEM_BASE}; char *base_ptr; + /* Ensure the desired device is valid */ if (bus >= ARRAY_SIZE(base_adr)) { printk(BIOS_ERR, "I2C: Only I2C controllers 0...6 are available.\n"); @@ -126,20 +128,19 @@ int i2c_init(unsigned bus) (pci_read_config32(dev, PCI_COMMAND) | 0x2));
/* Set up some settings of I2C controller */ - *((unsigned int *)(base_ptr + I2C_CTRL)) = (I2C_RESTART_EN | - (I2C_STANDARD_MODE << 1) | - I2C_MASTER_ENABLE); + write32(base_ptr + I2C_CTRL, + I2C_RESTART_EN | (I2C_STANDARD_MODE << 1) | I2C_MASTER_ENABLE); /* Adjust frequency for standard mode to 100 kHz */ /* The counter value can be computed by N=100MHz/2/I2C_CLK */ /* Thus, for 100 kHz I2C_CLK, N is 0x1F4 */ - *((unsigned int *)(base_ptr + I2C_SS_SCL_HCNT)) = 0x1f4; - *((unsigned int *)(base_ptr + I2C_SS_SCL_LCNT)) = 0x1f4; + write32(base_ptr + I2C_SS_SCL_HCNT, 0x1f4); + write32(base_ptr + I2C_SS_SCL_LCNT, 0x1f4); /* For 400 kHz, the counter value is 0x7d */ - *((unsigned int *)(base_ptr + I2C_FS_SCL_HCNT)) = 0x7d; - *((unsigned int *)(base_ptr + I2C_FS_SCL_LCNT)) = 0x7d; + write32(base_ptr + I2C_FS_SCL_HCNT, 0x7d); + write32(base_ptr + I2C_FS_SCL_LCNT, 0x7d);
/* Enable the I2C controller for operation */ - *((unsigned int *)(base_ptr + I2C_ENABLE)) = 0x1; + write32(base_ptr + I2C_ENABLE, 0x1);
printk(BIOS_INFO, "I2C: Controller %d enabled.\n", bus); return I2C_SUCCESS; @@ -177,20 +178,20 @@ int i2c_read(unsigned bus, unsigned chip, unsigned addr, if (stat != I2C_SUCCESS) return stat; /* Now we can program the desired slave address and start transfer */ - *((unsigned int *)(base_ptr + I2C_TARGET_ADR)) = (chip & 0xff); + write32(base_ptr + I2C_TARGET_ADR, chip & 0xff); /* Send address inside slave to read from */ - *((unsigned int *)(base_ptr + I2C_DATA_CMD)) = (addr & 0xff); + write32(base_ptr + I2C_DATA_CMD, addr & 0xff);
/* For the next byte we need a repeated start condition */ val = I2C_RW_CMD | I2C_RESTART; /* Now we can read desired amount of data over I2C */ for (i = 0; i < len; i++) { /* A read is initiated by writing dummy data to the DATA-register */ - *((unsigned int *)(base_ptr + I2C_DATA_CMD)) = val; + write32(base_ptr + I2C_DATA_CMD, val); stat = wait_rx_fifo(base_ptr); if (stat) return stat; - buf[i] = (*((unsigned int *)(base_ptr + I2C_DATA_CMD))) & 0xff; + buf[i] = read32(base_ptr + I2C_DATA_CMD) & 0xff; val = I2C_RW_CMD; if (i == (len - 2)) { /* For the last byte we need a stop condition to be generated */ @@ -232,10 +233,10 @@ int i2c_write(unsigned bus, unsigned chip, unsigned addr, return stat; } /* Program slave address to use for this transfer */ - *((unsigned int *)(base_ptr + I2C_TARGET_ADR)) = (chip & 0xff); + write32(base_ptr + I2C_TARGET_ADR, chip & 0xff);
/* Send address inside slave to write data to */ - *((unsigned int *)(base_ptr + I2C_DATA_CMD)) = (addr & 0xff); + write32(base_ptr + I2C_DATA_CMD, addr & 0xff);
for (i = 0; i < len; i++) { val = (unsigned int)(buf[i] & 0xff); /* Take only 8 bits */ @@ -247,7 +248,7 @@ int i2c_write(unsigned bus, unsigned chip, unsigned addr, if (stat) { return stat; } - *((unsigned int *)(base_ptr + I2C_DATA_CMD)) = val; + write32(base_ptr + I2C_DATA_CMD, val); } return I2C_SUCCESS; }
-
Ben Gardner