sb/intel/lynxpoint: Use unions for MEI registers
Wrap bitfield structs in unions to reduce pointer usage. This adds more
uses of the `mei_dump()` function, only used for debugging. Refactoring
the MEI CSR functions to not use pointers is done in a follow-up.
Change-Id: I4defbb8c0e7812bf95c672ce529959f67c34537a
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59623
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/southbridge/intel/lynxpoint/me.c b/src/southbridge/intel/lynxpoint/me.c
index a1625e8..15e2db0 100644
--- a/src/southbridge/intel/lynxpoint/me.c
+++ b/src/southbridge/intel/lynxpoint/me.c
@@ -40,9 +40,9 @@
/* MMIO base address for MEI interface */
static u8 *mei_base_address;
-static void mei_dump(void *ptr, int dword, int offset, const char *type)
+static void mei_dump(u32 dword, int offset, const char *type)
{
- struct mei_csr *csr;
+ union mei_csr csr;
if (!CONFIG(DEBUG_INTEL_ME))
return;
@@ -52,16 +52,12 @@
switch (offset) {
case MEI_H_CSR:
case MEI_ME_CSR_HA:
- csr = ptr;
- if (!csr) {
- printk(BIOS_SPEW, "ERROR: 0x%08x\n", dword);
- break;
- }
+ csr.raw = dword;
printk(BIOS_SPEW, "cbd=%u cbrp=%02u cbwp=%02u ready=%u "
- "reset=%u ig=%u is=%u ie=%u\n", csr->buffer_depth,
- csr->buffer_read_ptr, csr->buffer_write_ptr,
- csr->ready, csr->reset, csr->interrupt_generate,
- csr->interrupt_status, csr->interrupt_enable);
+ "reset=%u ig=%u is=%u ie=%u\n", csr.buffer_depth,
+ csr.buffer_read_ptr, csr.buffer_write_ptr,
+ csr.ready, csr.reset, csr.interrupt_generate,
+ csr.interrupt_status, csr.interrupt_enable);
break;
case MEI_ME_CB_RW:
case MEI_H_CB_WW:
@@ -77,53 +73,41 @@
* ME/MEI access helpers using memcpy to avoid aliasing.
*/
-static inline void mei_read_dword_ptr(void *ptr, int offset)
+static inline void read_host_csr(union mei_csr *csr)
{
- u32 dword = read32(mei_base_address + offset);
- memcpy(ptr, &dword, sizeof(dword));
- mei_dump(ptr, dword, offset, "READ");
+ csr->raw = read32(mei_base_address + MEI_H_CSR);
+ mei_dump(csr->raw, MEI_H_CSR, "READ");
}
-static inline void mei_write_dword_ptr(void *ptr, int offset)
+static inline void write_host_csr(union mei_csr *csr)
{
- u32 dword = 0;
- memcpy(&dword, ptr, sizeof(dword));
- write32(mei_base_address + offset, dword);
- mei_dump(ptr, dword, offset, "WRITE");
+ write32(mei_base_address + MEI_H_CSR, csr->raw);
+ mei_dump(csr->raw, MEI_H_CSR, "WRITE");
}
-static inline void read_host_csr(struct mei_csr *csr)
+static inline void read_me_csr(union mei_csr *csr)
{
- mei_read_dword_ptr(csr, MEI_H_CSR);
-}
-
-static inline void write_host_csr(struct mei_csr *csr)
-{
- mei_write_dword_ptr(csr, MEI_H_CSR);
-}
-
-static inline void read_me_csr(struct mei_csr *csr)
-{
- mei_read_dword_ptr(csr, MEI_ME_CSR_HA);
+ csr->raw = read32(mei_base_address + MEI_ME_CSR_HA);
+ mei_dump(csr->raw, MEI_ME_CSR_HA, "READ");
}
static inline void write_cb(u32 dword)
{
write32(mei_base_address + MEI_H_CB_WW, dword);
- mei_dump(NULL, dword, MEI_H_CB_WW, "WRITE");
+ mei_dump(dword, MEI_H_CB_WW, "WRITE");
}
static inline u32 read_cb(void)
{
u32 dword = read32(mei_base_address + MEI_ME_CB_RW);
- mei_dump(NULL, dword, MEI_ME_CB_RW, "READ");
+ mei_dump(dword, MEI_ME_CB_RW, "READ");
return dword;
}
/* Wait for ME ready bit to be asserted */
static int mei_wait_for_me_ready(void)
{
- struct mei_csr me;
+ union mei_csr me;
unsigned int try = ME_RETRY;
while (try--) {
@@ -139,7 +123,7 @@
static void mei_reset(void)
{
- struct mei_csr host;
+ union mei_csr host;
if (mei_wait_for_me_ready() < 0)
return;
@@ -161,9 +145,9 @@
write_host_csr(&host);
}
-static int mei_send_packet(struct mei_header *mei, void *req_data)
+static int mei_send_packet(union mei_header *mei, void *req_data)
{
- struct mei_csr host;
+ union mei_csr host;
unsigned int ndata, n;
u32 *data;
@@ -198,7 +182,7 @@
}
/* Write MEI header */
- mei_write_dword_ptr(mei, MEI_H_CB_WW);
+ write_cb(mei->raw);
ndata--;
/* Write message data */
@@ -218,11 +202,11 @@
static int mei_send_data(u8 me_address, u8 host_address,
void *req_data, int req_bytes)
{
- struct mei_header header = {
+ union mei_header header = {
.client_address = me_address,
.host_address = host_address,
};
- struct mei_csr host;
+ union mei_csr host;
int current = 0;
u8 *req_ptr = req_data;
@@ -254,7 +238,7 @@
static int mei_send_header(u8 me_address, u8 host_address,
void *header, int header_len, int complete)
{
- struct mei_header mei = {
+ union mei_header mei = {
.client_address = me_address,
.host_address = host_address,
.length = header_len,
@@ -266,8 +250,8 @@
static int mei_recv_msg(void *header, int header_bytes,
void *rsp_data, int rsp_bytes)
{
- struct mei_header mei_rsp;
- struct mei_csr me, host;
+ union mei_header mei_rsp;
+ union mei_csr me, host;
unsigned int ndata, n;
unsigned int expected;
u32 *data;
@@ -299,7 +283,7 @@
}
/* Read and verify MEI response header from the ME */
- mei_read_dword_ptr(&mei_rsp, MEI_ME_CB_RW);
+ mei_rsp.raw = read_cb();
if (!mei_rsp.is_complete) {
printk(BIOS_ERR, "ME: response is not complete\n");
return -1;
@@ -410,7 +394,7 @@
*/
static void intel_me_mbp_give_up(struct device *dev)
{
- struct mei_csr csr;
+ union mei_csr csr;
pci_write_config32(dev, PCI_ME_H_GS2, PCI_ME_MBP_GIVE_UP);
@@ -656,7 +640,7 @@
static int intel_mei_setup(struct device *dev)
{
struct resource *res;
- struct mei_csr host;
+ union mei_csr host;
/* Find the MMIO base for the ME interface */
res = probe_resource(dev, PCI_BASE_ADDRESS_0);
@@ -726,7 +710,7 @@
static u32 me_to_host_words_pending(void)
{
- struct mei_csr me;
+ union mei_csr me;
read_me_csr(&me);
if (!me.ready)
return 0;
@@ -735,7 +719,7 @@
}
struct mbp_payload {
- struct mbp_header header;
+ union mbp_header header;
u32 data[0];
};
@@ -747,9 +731,9 @@
*/
static int intel_me_read_mbp(struct me_bios_payload *mbp_data, struct device *dev)
{
- struct mbp_header mbp_hdr;
+ union mbp_header mbp_hdr;
u32 me2host_pending;
- struct mei_csr host;
+ union mei_csr host;
union me_hfs2 hfs2 = { .raw = pci_read_config32(dev, PCI_ME_HFS2) };
struct mbp_payload *mbp;
int i;
@@ -766,7 +750,7 @@
}
/* we know for sure that at least the header is there */
- mei_read_dword_ptr(&mbp_hdr, MEI_ME_CB_RW);
+ mbp_hdr.raw = read_cb();
if ((mbp_hdr.num_entries > (mbp_hdr.mbp_size / 2)) ||
(me2host_pending < mbp_hdr.mbp_size)) {
@@ -785,7 +769,7 @@
i = 0;
while (i != me2host_pending) {
- mei_read_dword_ptr(&mbp->data[i], MEI_ME_CB_RW);
+ mbp->data[i] = read_cb();
i++;
}