spi_mpc83xx: use brg-frequency for SPI in QE
In case of QE we can use brg-frequency (which is qeclk/2).
Thus no need to divide sysclk in the spi_mpc83xx.
This patch also adds code to use get_brgfreq() on QE chips.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/sysdev/fsl_soc.c b/arch/powerpc/sysdev/fsl_soc.c
index 26f7d83..6f81dd5 100644
--- a/arch/powerpc/sysdev/fsl_soc.c
+++ b/arch/powerpc/sysdev/fsl_soc.c
@@ -75,7 +75,7 @@
EXPORT_SYMBOL(get_immrbase);
-#if defined(CONFIG_CPM2) || defined(CONFIG_8xx)
+#if defined(CONFIG_CPM2) || defined(CONFIG_QUICC_ENGINE) || defined(CONFIG_8xx)
static u32 brgfreq = -1;
@@ -100,11 +100,21 @@
/* Legacy device binding -- will go away when no users are left. */
node = of_find_node_by_type(NULL, "cpm");
+ if (!node)
+ node = of_find_compatible_node(NULL, NULL, "fsl,qe");
+ if (!node)
+ node = of_find_node_by_type(NULL, "qe");
+
if (node) {
prop = of_get_property(node, "brg-frequency", &size);
if (prop && size == 4)
brgfreq = *prop;
+ if (brgfreq == -1 || brgfreq == 0) {
+ prop = of_get_property(node, "bus-frequency", &size);
+ if (prop && size == 4)
+ brgfreq = *prop / 2;
+ }
of_node_put(node);
}
@@ -1273,22 +1283,32 @@
{
struct device_node *np;
unsigned int i;
- const u32 *sysclk;
+ u32 sysclk = -1;
/* SPI controller is either clocked from QE or SoC clock */
- np = of_find_compatible_node(NULL, NULL, "fsl,qe");
- if (!np)
- np = of_find_node_by_type(NULL, "qe");
+#ifdef CONFIG_QUICC_ENGINE
+ sysclk = get_brgfreq();
+#endif
+ if (sysclk == -1) {
+ const u32 *freq;
+ int size;
- if (!np)
np = of_find_node_by_type(NULL, "soc");
+ if (!np)
+ return -ENODEV;
- if (!np)
- return -ENODEV;
+ freq = of_get_property(np, "clock-frequency", &size);
+ if (!freq || size != sizeof(*freq) || *freq == 0) {
+ freq = of_get_property(np, "bus-frequency", &size);
+ if (!freq || size != sizeof(*freq) || *freq == 0) {
+ of_node_put(np);
+ return -ENODEV;
+ }
+ }
- sysclk = of_get_property(np, "bus-frequency", NULL);
- if (!sysclk)
- return -ENODEV;
+ sysclk = *freq;
+ of_node_put(np);
+ }
for (np = NULL, i = 1;
(np = of_find_compatible_node(np, "spi", "fsl_spi")) != NULL;
@@ -1305,7 +1325,7 @@
memset(res, 0, sizeof(res));
- pdata.sysclk = *sysclk;
+ pdata.sysclk = sysclk;
prop = of_get_property(np, "reg", NULL);
if (!prop)
diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 4580b9c..04f7cd9 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -436,11 +436,7 @@
mpc83xx_spi->qe_mode = pdata->qe_mode;
mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
-
- if (mpc83xx_spi->qe_mode)
- mpc83xx_spi->spibrg = pdata->sysclk / 2;
- else
- mpc83xx_spi->spibrg = pdata->sysclk;
+ mpc83xx_spi->spibrg = pdata->sysclk;
mpc83xx_spi->rx_shift = 0;
mpc83xx_spi->tx_shift = 0;