[PATCH v2 2/2] spi: fsl-spi: Allow dynamic allocation of CPM1 parameter RAM

[Christophe Leroy]

On CPM1, the SPI parameter RAM has a default location. In order to use SPI while
using SCC2 with features like QMC or Ethernet, it is necessary to relocate SPI
parameter RAM in a free location in the CPM dual port RAM. With this patch,
when "fsl,cpm1-spi-reloc" instead of "fsl,cpm1-spi" compatible is set in the
device tree, the parameter RAM for SPI is dynamically allocated
with cpm_muram_alloc().

Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>

---
Changes from v1 to v2: using OF compatible instead of compile time option

 drivers/spi/spi-fsl-cpm.c   | 3 +++
 drivers/spi/spi-fsl-lib.c   | 2 ++
 include/linux/fsl_devices.h | 1 +
 3 files changed, 6 insertions(+)

diff --git a/drivers/spi/spi-fsl-cpm.c b/drivers/spi/spi-fsl-cpm.c
index 0f3a912..048ca5f 100644
--- a/drivers/spi/spi-fsl-cpm.c
+++ b/drivers/spi/spi-fsl-cpm.c
@@ -261,6 +261,9 @@ static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
 	if (mspi->flags & SPI_CPM2) {
 		pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
 		out_be16(spi_base, pram_ofs);
+	} else if (mspi->flags & SPI_CPM1_RELOC) {
+		pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 32);
+		out_be16(spi_base, pram_ofs);
 	} else {
 		u16 rpbase = in_be16(spi_base);
 
diff --git a/drivers/spi/spi-fsl-lib.c b/drivers/spi/spi-fsl-lib.c
index c3f7802..e9db4c5 100644
--- a/drivers/spi/spi-fsl-lib.c
+++ b/drivers/spi/spi-fsl-lib.c
@@ -227,6 +227,8 @@ int of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 		pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 	else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 		pdata->flags = SPI_CPM_MODE | SPI_CPM1;
+	else if (of_device_is_compatible(np, "fsl,cpm1-spi-reloc"))
+		pdata->flags = SPI_CPM_MODE | SPI_CPM1 | SPI_CPM1_RELOC;
 
 	return 0;
 }
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index a82296a..417ad52 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -123,6 +123,7 @@ struct fsl_spi_platform_data {
 #define SPI_CPM1		(1 << 2) /* SPI unit is in CPM1 block */
 #define SPI_CPM2		(1 << 3) /* SPI unit is in CPM2 block */
 #define SPI_QE			(1 << 4) /* SPI unit is in QE block */
+#define SPI_CPM1_RELOC		(1 << 5) /* SPI pram has to be relocated */
 	/* board specific information */
 	u16	max_chipselect;
 	void	(*cs_control)(struct spi_device *spi, bool on);
-- 
2.1.0